Hello > Wesley, > > thanks for your reply. I was surprised about the limited information > too. Sadly (?), I can't reproduce the error any more... > > David > > > > On 10/02/10 11:13, wesley chun wrote: >>> I just wrote this message, but after restarting ipython all worked >>> fine. >>> How is it to be explained that I first had a namespace error which, >>> after a >>> restart (and not merely a new "run Sande_celsius-main.py"), went >>> away? I >>> mean, surely the namespace should not be impacted by ipython at all!? >>> : >>> # file: Sande_celsius-main.py >>> from Sande_my_module import c_to_f >>> celsius = float(raw_input("Enter a temperature in Celsius: ")) >>> fahrenheit = c_to_f(celsius) >>> print "That's ", fahrenheit, " degrees Fahrenheit" >>> >>> # this is the file Sande_my_module.py >>> # we're going to use it in another program >>> def c_to_f(celsius): >>> fahrenheit = celsius * 9.0 / 5 + 32 >>> return fahrenheit >>> >>> When I run Sande_celsius-main.py, I get the following error: >>> >>> NameError: global name 'celsius' is not defined >>> WARNING: Failure executing file: >> >> >> Python interpreters including the standard one or IPython should tell >> you a lot more than that. how are you executing this code? would it be >> possible to do so from the command-line? you should get a more verbose >> error message that you can post here. >> >> best regards, >> -- wesley > Your response to Wesley should have been here, instead of at the top. Please don't top-post on this forum. I don't use iPython, so this is just a guess. But perhaps the problem is that once you've imported the code, then change it, it's trying to run the old code instead of the changed code. Try an experiment in your environment. Deliberately add an error to Sande_celsius-main.py, and run it. Then correct it, and run it again, to see if it notices the fix. The changes I'd try in this experiment are to first change the name on the celsius= line to celsius2= and after running and getting the error, change the following line to call celsius2(). If it gets an error, notice what symbol it complains about. HTH DaveA From steve at pearwood.info Wed Feb 10 15:13:39 2010 From: steve at pearwood.info (Steven D'Aprano) Date: Thu, 11 Feb 2010 01:13:39 +1100 Subject: [Tutor] string to list In-Reply-To: <4B72B584.9020802@cooptel.net> References: <4B72B584.9020802@cooptel.net> Message-ID: <201002110113.40241.steve@pearwood.info> On Thu, 11 Feb 2010 12:32:52 am Owain Clarke wrote: > My son was doing a statistics project in which he had to sort some > data by either one of two sets of numbers, representing armspan and > height of a group of children - a boring and painstaking job. I came > across this piece of code:- > > li=[[2,6],[1,3],[5,4]] # would also work with li=[(2,6),(1,3),(5,4)] > li.sort(key=lambda x:x[1] ) > print li > > It occurred to me that I could adapt this so that he could input his > data at the command line and then sort by x:x[0] or x:x[1]. And I > have not discovered a way of inputting a list, only strings or > various number types. Which command line do you mean? If you are talking about the Python interactive interpreter, then you can input either lists or strings: >>> li = [1, 2, 3] # a list >>> li = "[1, 2, 3]" # a string If you mean the external shell (say, "bash" under Linux or the DOS command line in Windows, or similar) then you can only input strings -- everything is a string in such shells. There are two ways to convert such strings to lists: the easy, unsafe way; or the slightly more difficult but safer way. Think of it like The Force, where the Dark Side is simpler and more attractive but ultimately more dangerous :) First, the easy way. If you absolutely trust the source of the data, then you can use the eval function: >>> s = "[1, 2, 3]" # quote marks make it a string >>> li = eval(s) The interpreter will read the string s as a Python expression, and do whatever it says. In this example, it says "make a list with the numbers 1, 2 and 3 in it". But it could say *anything*, like "erase the hard disk", and Python would dutifully do what it is told. This is why eval is easy and fast but dangerous, and you must absolutely trust the source of the string. Alternatively, you could do this: >>> s = "1 2 3 4" # numbers separated by spaces >>> li = s.split() # li now contains the strings "1", "2" etc. >>> li = map(int, li) # convert the strings to actual ints >>> print li [1, 2, 3, 4] Naturally the string s would come from the shell, otherwise there is no point! If you are typing the data directly into the Python interpreter, you would enter it directly as a list and not a string. Hope this helps, -- Steven D'Aprano From kent37 at tds.net Wed Feb 10 15:19:06 2010 From: kent37 at tds.net (Kent Johnson) Date: Wed, 10 Feb 2010 09:19:06 -0500 Subject: [Tutor] string to list In-Reply-To: <4B72B584.9020802@cooptel.net> References: <4B72B584.9020802@cooptel.net> Message-ID: <1c2a2c591002100619p5beef182wa429421c7742bc55@mail.gmail.com> On Wed, Feb 10, 2010 at 8:32 AM, Owain Clarke wrote: > My son was doing a statistics project in which he had to sort some data by > either one of two sets of numbers, representing armspan and height of a > group of children - a boring and painstaking job. ?I came across this piece > of code:- > > li=[[2,6],[1,3],[5,4]] ?# would also work with li=[(2,6),(1,3),(5,4)] > li.sort(key=lambda x:x[1] ) > print li > > It occurred to me that I could adapt this so that he could input his data at > the command line and then sort by x:x[0] or x:x[1]. ?And I have not > discovered a way of inputting a list, only strings or various number types. I would do this by reading the data from a file, that way the data entry is simpler, easier to check and correct, easy to reuse, etc.. Create a file that looks like this: 2 6 1 3 5 4 Read it with code like f = open('data.txt') data = [] for line in f: line_data = [ int(x) for x in line.split() ] data.append(line_data) or if you like map() and one-line list comprehensions: data = [ map(int, line.split()) for line in open('data.txt') ] Then you can sort & process data to your hearts content. You could also just hard-code the data into your program as a literal list. Kent From eike.welk at gmx.net Wed Feb 10 15:24:46 2010 From: eike.welk at gmx.net (Eike Welk) Date: Wed, 10 Feb 2010 15:24:46 +0100 Subject: [Tutor] string to list In-Reply-To: <4B72B584.9020802@cooptel.net> References: <4B72B584.9020802@cooptel.net> Message-ID: <201002101524.46949.eike.welk@gmx.net> On Wednesday February 10 2010 14:32:52 Owain Clarke wrote: > My son was doing a statistics project in which he had to sort some data by > either one of two sets of numbers, representing armspan and height of a > group of children - a boring and painstaking job. I came across this > piece of code:- > > li=[[2,6],[1,3],[5,4]] # would also work with li=[(2,6),(1,3),(5,4)] > li.sort(key=lambda x:x[1] ) > print li > > It occurred to me that I could adapt this so that he could input his data > at the command line and then sort by x:x[0] or x:x[1]. And I have not > discovered a way of inputting a list, only strings or various number > types. I would let him enter the data into the program text directly, or parse a text file with a simple format. Something like: in_data = [ #arm span, height [2 , 6 ], [1 , 3 ], [5 , 4 ], [ , ], [ , ], [ , ], ] This way the computation can be repeated when there were errors int the data. Otherwise one error might spoil all the work he did while typing in the data. Designing a simple text representation of the data and interpreting it with a computer program, is much more easy that writing good user interfaces. For the same reason Unix, a concept from the late 1960s, is still doing relatively well. Eike. From stefan_ml at behnel.de Wed Feb 10 15:28:28 2010 From: stefan_ml at behnel.de (Stefan Behnel) Date: Wed, 10 Feb 2010 15:28:28 +0100 Subject: [Tutor] string to list In-Reply-To: <4B72B584.9020802@cooptel.net> References: <4B72B584.9020802@cooptel.net> Message-ID: Owain Clarke, 10.02.2010 14:32: >> You may want to add a little bit about your use case. Is that really >> the input you >> have to deal with? Where does it come from? Can you control the >> format? What do >> you want to do with the list you extract from the string? >> >> All of that may have an impact on the right solution. > > My son was doing a statistics project in which he had to sort some data > by either one of two sets of numbers, representing armspan and height of > a group of children - a boring and painstaking job. Thanks for the explanation, that certainly clears it up. > I came across this piece of code:- > > li=[[2,6],[1,3],[5,4]] # would also work with li=[(2,6),(1,3),(5,4)] > li.sort(key=lambda x:x[1] ) > print li > > It occurred to me that I could adapt this so that he could input his > data at the command line and then sort by x:x[0] or x:x[1]. And I have > not discovered a way of inputting a list, only strings or various number > types. I would rather put them into a file one-per-line, e.g. 2,6 1,3 5,4 and then read that in as input. That way, you can reuse the input multiple times, even if you discover that your program has a bug or needs a new feature, or whatever. Having to retype the data will quickly get really cumbersome. Something like this should do the job: children_properties = [] with file("thefile.txt") as f: for line in f: if line.count(',') != 1: # broken line? print("Ignoring malformed line '%s'" % line) continue armspan, height = map(int, line.split(',')) children_properties.append( (armspan, height) ) Then sort and print as you see fit. > I realise that I am a bit out of my depth here, but Python just seems > like so much fun!! The beauty of Python for people who are just starting programming is that so many things are so surprisingly simply to do that you really quickly get to think about rather tricky problems, instead of being blocked by syntax. Keep up the pace! :) Stefan From simbobo at cooptel.net Wed Feb 10 15:51:34 2010 From: simbobo at cooptel.net (Owain Clarke) Date: Wed, 10 Feb 2010 14:51:34 +0000 Subject: [Tutor] string to list In-Reply-To: References: Message-ID: <4B72C7F6.1010604@cooptel.net> An HTML attachment was scrubbed... URL: From grigor.kolev at gmail.com Wed Feb 10 20:30:52 2010 From: grigor.kolev at gmail.com (Grigor Kolev) Date: Wed, 10 Feb 2010 21:30:52 +0200 Subject: [Tutor] html and python Message-ID: <1265830252.8722.1.camel@dedal-laptop> Hi. I want to make a list of E-mail, photos and some additional data. But I want this list to be displayed in one site. How can I send data from a list of site page. Which module should I use -- Grigor Kolev From vinces1979 at gmail.com Wed Feb 10 20:33:07 2010 From: vinces1979 at gmail.com (vince spicer) Date: Wed, 10 Feb 2010 13:33:07 -0600 Subject: [Tutor] html and python In-Reply-To: <1265830252.8722.1.camel@dedal-laptop> References: <1265830252.8722.1.camel@dedal-laptop> Message-ID: <1e53c511002101133ne417527x4ee6e590a7a451de@mail.gmail.com> On Wed, Feb 10, 2010 at 1:30 PM, Grigor Kolev wrote: > Hi. > I want to make a list of E-mail, photos and some additional data. > But I want this list to be displayed in one site. > How can I send data from a list of site page. Which module should I use > -- > Grigor Kolev > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > do you have any code currently? -------------- next part -------------- An HTML attachment was scrubbed... URL: From kent37 at tds.net Wed Feb 10 20:39:50 2010 From: kent37 at tds.net (Kent Johnson) Date: Wed, 10 Feb 2010 14:39:50 -0500 Subject: [Tutor] html and python In-Reply-To: <1265830252.8722.1.camel@dedal-laptop> References: <1265830252.8722.1.camel@dedal-laptop> Message-ID: <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> On Wed, Feb 10, 2010 at 2:30 PM, Grigor Kolev wrote: > Hi. > I want to make a list of E-mail, photos and some additional data. > But I want this list to be displayed in one site. > How can I send data from a list of site page. Which module should I use I don't understand "send data from a list of site page". Are you making a web site? Dynamic or static? Are you asking how to build an HTML page in Python? Kent From dananzoff at gmail.com Wed Feb 10 20:40:40 2010 From: dananzoff at gmail.com (Harya Dananjaya) Date: Thu, 11 Feb 2010 04:40:40 +0900 Subject: [Tutor] Compile py to exe in ubuntu Message-ID: <4B730BB8.1030004@gmail.com> Can I compile my python source to exe in ubuntu? if I can do it, which compiler can do it? Thanks you, Harya Dananjaya From vinces1979 at gmail.com Wed Feb 10 20:41:43 2010 From: vinces1979 at gmail.com (vince spicer) Date: Wed, 10 Feb 2010 13:41:43 -0600 Subject: [Tutor] html and python In-Reply-To: <1265830252.8722.1.camel@dedal-laptop> References: <1265830252.8722.1.camel@dedal-laptop> Message-ID: <1e53c511002101141ocab158dn6e6e1a52372382d7@mail.gmail.com> On Wed, Feb 10, 2010 at 1:30 PM, Grigor Kolev wrote: > Hi. > I want to make a list of E-mail, photos and some additional data. > But I want this list to be displayed in one site. > How can I send data from a list of site page. Which module should I use > -- > Grigor Kolev > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > Your best bet is show us some code .. then we can help. Vince -------------- next part -------------- An HTML attachment was scrubbed... URL: From grigor.kolev at gmail.com Wed Feb 10 20:49:25 2010 From: grigor.kolev at gmail.com (Grigor Kolev) Date: Wed, 10 Feb 2010 21:49:25 +0200 Subject: [Tutor] html and python In-Reply-To: <1e53c511002101133ne417527x4ee6e590a7a451de@mail.gmail.com> References: <1265830252.8722.1.camel@dedal-laptop> <1e53c511002101133ne417527x4ee6e590a7a451de@mail.gmail.com> Message-ID: <1265831365.8722.13.camel@dedal-laptop> ? 13:33 -0600 ?? 10.02.2010 (??), vince spicer ??????: > On Wed, Feb 10, 2010 at 1:30 PM, Grigor Kolev > wrote: > Hi. > I want to make a list of E-mail, photos and some additional > data. > But I want this list to be displayed in one site. > How can I send data from a list of site page. Which module > should I use > -- > Grigor Kolev > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > > do you have any code currently? No have. Data is something like this. [{'grigor.kolev at gmail.com' : {name: 'Grigor', age: 26, photo: r'/home/user/photoname'}, {Next mail}] But I do not know how to send data in html. I want to make loop who pars the list and show data in the site. -- Grigor Kolev From vinces1979 at gmail.com Wed Feb 10 20:49:53 2010 From: vinces1979 at gmail.com (vince spicer) Date: Wed, 10 Feb 2010 13:49:53 -0600 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <4B730BB8.1030004@gmail.com> References: <4B730BB8.1030004@gmail.com> Message-ID: <1e53c511002101149y4197a86apf3a41c305bccd1be@mail.gmail.com> On Wed, Feb 10, 2010 at 1:40 PM, Harya Dananjaya wrote: > Can I compile my python source to exe in ubuntu? > if I can do it, which compiler can do it? > > Thanks you, > > Harya Dananjaya > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > 1. Ubuntu and linux in general don't use exe per say 2. Python can be compiled but not usually in the way you are thinking 3. you might check out http://pypi.python.org/pypi/bbfreeze/ Vince -------------- next part -------------- An HTML attachment was scrubbed... URL: From waynejwerner at gmail.com Wed Feb 10 20:47:50 2010 From: waynejwerner at gmail.com (Wayne Werner) Date: Wed, 10 Feb 2010 13:47:50 -0600 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <4B730BB8.1030004@gmail.com> References: <4B730BB8.1030004@gmail.com> Message-ID: <333efb451002101147t648f1fcfk2c62501014a00dba@mail.gmail.com> On Wed, Feb 10, 2010 at 1:40 PM, Harya Dananjaya wrote: > Can I compile my python source to exe in ubuntu? > if I can do it, which compiler can do it? > > Thanks you, > > Harya Dananjaya > Do you mean a windows executable? Not really. Why do you want an .exe anyway? Python code is (usually) cross-platform. -Wayne -------------- next part -------------- An HTML attachment was scrubbed... URL: From grigor.kolev at gmail.com Wed Feb 10 20:56:59 2010 From: grigor.kolev at gmail.com (Grigor Kolev) Date: Wed, 10 Feb 2010 21:56:59 +0200 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <4B730BB8.1030004@gmail.com> References: <4B730BB8.1030004@gmail.com> Message-ID: <1265831819.8722.22.camel@dedal-laptop> ? 04:40 +0900 ?? 11.02.2010 (??), Harya Dananjaya ??????: > Can I compile my python source to exe in ubuntu? > if I can do it, which compiler can do it? > > Thanks you, > > Harya Dananjaya > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor Use cx_freeze but you cannot make exe in ubuntu must use Windows -- Grigor Kolev From kent37 at tds.net Wed Feb 10 21:02:41 2010 From: kent37 at tds.net (Kent Johnson) Date: Wed, 10 Feb 2010 15:02:41 -0500 Subject: [Tutor] html and python In-Reply-To: <1265831670.8722.18.camel@dedal-laptop> References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> <1265831670.8722.18.camel@dedal-laptop> Message-ID: <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> On Wed, Feb 10, 2010 at 2:54 PM, Grigor Kolev wrote: > ? 14:39 -0500 ?? 10.02.2010 (??), Kent Johnson ??????: >> On Wed, Feb 10, 2010 at 2:30 PM, Grigor Kolev wrote: >> > Hi. >> > I want to make a list of E-mail, photos and some additional data. >> > But I want this list to be displayed in one site. >> > How can I send data from a list of site page. Which module should I use >> >> I don't understand "send data from a list of site page". Are you >> making a web site? Dynamic or static? Are you asking how to build an >> HTML page in Python? >> >> Kent > Yes how can I build html file with Python. > And how can i make a script who start every day and refresh the html pages HTML is just text. Do you know what you want your HTML to look like? In the simplest case, you can write the HTML directly from Python to a file. For more complicated files you may want to use some kind of templating or HTML-generation library. You can schedule a script to run every day using cron (*nix) or Scheduled Tasks (Windows). What is your level of experience? You will get better answers if you give us more information in your questions. Don't make us work for every bit of your problem. Kent From grigor.kolev at gmail.com Wed Feb 10 21:26:47 2010 From: grigor.kolev at gmail.com (Grigor Kolev) Date: Wed, 10 Feb 2010 22:26:47 +0200 Subject: [Tutor] html and python In-Reply-To: <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> <1265831670.8722.18.camel@dedal-laptop> <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> Message-ID: <1265833607.8722.24.camel@dedal-laptop> ? 15:02 -0500 ?? 10.02.2010 (??), Kent Johnson ??????: > On Wed, Feb 10, 2010 at 2:54 PM, Grigor Kolev wrote: > > ? 14:39 -0500 ?? 10.02.2010 (??), Kent Johnson ??????: > >> On Wed, Feb 10, 2010 at 2:30 PM, Grigor Kolev wrote: > >> > Hi. > >> > I want to make a list of E-mail, photos and some additional data. > >> > But I want this list to be displayed in one site. > >> > How can I send data from a list of site page. Which module should I use > >> > >> I don't understand "send data from a list of site page". Are you > >> making a web site? Dynamic or static? Are you asking how to build an > >> HTML page in Python? > >> > >> Kent > > Yes how can I build html file with Python. > > And how can i make a script who start every day and refresh the html pages > > HTML is just text. Do you know what you want your HTML to look like? > In the simplest case, you can write the HTML directly from Python to a > file. For more complicated files you may want to use some kind of > templating or HTML-generation library. > > You can schedule a script to run every day using cron (*nix) or > Scheduled Tasks (Windows). > > What is your level of experience? > > You will get better answers if you give us more information in your > questions. Don't make us work for every bit of your problem. > > Kent I apologize to my question is incorrectly set. We have a mail list and we want to do in site a list of all participants with their photos and names. List with people is saved in the txt file. I want to open this file. Take all mail address and to do formating the data. Then with loop to do parsing all data and to do send in the html. I can open and save as plain text document. File = file(r'/home/user/test.html', 'w') But if I refresh the data every day it by a slowly. -- Grigor Kolev From invincible_patriot at hotmail.com Wed Feb 10 22:27:32 2010 From: invincible_patriot at hotmail.com (invincible patriot) Date: Wed, 10 Feb 2010 21:27:32 +0000 Subject: [Tutor] need idea In-Reply-To: <1265833607.8722.24.camel@dedal-laptop> References: <1265830252.8722.1.camel@dedal-laptop>, <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com>, <1265831670.8722.18.camel@dedal-laptop>, <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com>, <1265833607.8722.24.camel@dedal-laptop> Message-ID: hi i want to compare a string with a dictionary or u can say that i want to take user input A STRING, and want to compare each character of that string with the KEYS in the dictionary, and then i wana print the values for the characters that are present in that strinng that we got as the input and were present in the dictionary as well can you please give me some idea how to do that what i hav done is that 1) I have made a dictionary with the keys and the values 2) I have taken the input from the user and hav saved it into a variable not i wana compare string that was given to us and replace them with the values given in the dictionary please let me know _________________________________________________________________ Hotmail: Trusted email with Microsoft?s powerful SPAM protection. http://clk.atdmt.com/GBL/go/201469226/direct/01/ -------------- next part -------------- An HTML attachment was scrubbed... URL: From invincible_patriot at hotmail.com Wed Feb 10 22:29:26 2010 From: invincible_patriot at hotmail.com (invincible patriot) Date: Wed, 10 Feb 2010 21:29:26 +0000 Subject: [Tutor] Needleman-Wunsch algorithm In-Reply-To: <1265833607.8722.24.camel@dedal-laptop> References: <1265830252.8722.1.camel@dedal-laptop>, <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com>, <1265831670.8722.18.camel@dedal-laptop>, <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com>, <1265833607.8722.24.camel@dedal-laptop> Message-ID: hi i hope every one knows about the needleman wunsch algo i am trying to do the same task, can some one give me an outline as to how should i start after taking 2 input strings from the user.. _________________________________________________________________ Hotmail: Powerful Free email with security by Microsoft. http://clk.atdmt.com/GBL/go/201469230/direct/01/ -------------- next part -------------- An HTML attachment was scrubbed... URL: From waynejwerner at gmail.com Wed Feb 10 22:51:16 2010 From: waynejwerner at gmail.com (Wayne Werner) Date: Wed, 10 Feb 2010 15:51:16 -0600 Subject: [Tutor] Needleman-Wunsch algorithm In-Reply-To: References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> <1265831670.8722.18.camel@dedal-laptop> <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> <1265833607.8722.24.camel@dedal-laptop> Message-ID: <333efb451002101351x56326595p811e4ee13e7d6346@mail.gmail.com> On Wed, Feb 10, 2010 at 3:29 PM, invincible patriot < invincible_patriot at hotmail.com> wrote: > hi > i hope every one knows about the needleman wunsch algo > Never heard of it > i am trying to do the same task, > can some one give me an outline as to how should i start after taking 2 > input strings from the user. > Where do you think you should start? Perhaps if you explain the algorithm you'll get some ideas about where to start... HTH, Wayne -- To be considered stupid and to be told so is more painful than being called gluttonous, mendacious, violent, lascivious, lazy, cowardly: every weakness, every vice, has found its defenders, its rhetoric, its ennoblement and exaltation, but stupidity hasn?t. - Primo Levi -------------- next part -------------- An HTML attachment was scrubbed... URL: From kent37 at tds.net Wed Feb 10 23:09:52 2010 From: kent37 at tds.net (Kent Johnson) Date: Wed, 10 Feb 2010 17:09:52 -0500 Subject: [Tutor] need idea In-Reply-To: References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> <1265831670.8722.18.camel@dedal-laptop> <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> <1265833607.8722.24.camel@dedal-laptop> Message-ID: <1c2a2c591002101409v447e2e7gc6394c3caf357d36@mail.gmail.com> On Wed, Feb 10, 2010 at 4:27 PM, invincible patriot wrote: > hi > i want to compare a string with a dictionary > or u can say that i want to take user input A STRING, and want to compare > each character of that string with the KEYS? in the dictionary, and then i > wana print the values for the characters that are present in that strinng > that we got as the input and were present in the dictionary as well Please give an example input, dictionary and desired output. > can you please give me some idea how to do that > > what i hav done is that > 1) I have made a dictionary with the keys and the values > 2) I have taken the input from the user and hav saved it into a variable > > not i wana compare string that was given to us and replace them with the > values given in the dictionary You probably want some combination of iteration over the input string and dict.get(). Kent From andreengels at gmail.com Wed Feb 10 23:10:38 2010 From: andreengels at gmail.com (Andre Engels) Date: Wed, 10 Feb 2010 23:10:38 +0100 Subject: [Tutor] need idea In-Reply-To: References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> <1265831670.8722.18.camel@dedal-laptop> <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> <1265833607.8722.24.camel@dedal-laptop> Message-ID: <6faf39c91002101410w4ff0169cof846d70fc801fff5@mail.gmail.com> On Wed, Feb 10, 2010 at 10:27 PM, invincible patriot wrote: > hi > i want to compare a string with a dictionary > or u can say that i want to take user input A STRING, and want to compare > each character of that string with the KEYS? in the dictionary, and then i > wana print the values for the characters that are present in that strinng > that we got as the input and were present in the dictionary as well > > can you please give me some idea how to do that > > what i hav done is that > 1) I have made a dictionary with the keys and the values > 2) I have taken the input from the user and hav saved it into a variable > > not i wana compare string that was given to us and replace them with the > values given in the dictionary It's not yet completely clear to me what you want, but the following should help you: Let str be the string, and dict the dictionary, then: [c for c in str if c in dict] will give you the characters in the string that are keys in the dictionary. -- Andr? Engels, andreengels at gmail.com From invincible_patriot at hotmail.com Thu Feb 11 00:12:05 2010 From: invincible_patriot at hotmail.com (invincible patriot) Date: Wed, 10 Feb 2010 23:12:05 +0000 Subject: [Tutor] need idea In-Reply-To: <6faf39c91002101410w4ff0169cof846d70fc801fff5@mail.gmail.com> References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com>, <1265831670.8722.18.camel@dedal-laptop> <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com>, <1265833607.8722.24.camel@dedal-laptop> , <6faf39c91002101410w4ff0169cof846d70fc801fff5@mail.gmail.com> Message-ID: thanks let me clear you that what i am trying to do suppose we hav a input string and a dict our_dict={'a':'u', 't':'a', 'c':'g', 'g':'c'} input_string='atcg' now what i wana do is that where ever we are having 'a' i wana replace it with 'u', 't' with 'a' and so on i tried using input_string.replace('a', 'u') but it is replacing only one character i wana replace these 4 characters according to the dictionary i hope it is now clear kindly let me know how to proceed now > From: andreengels at gmail.com > Date: Wed, 10 Feb 2010 23:10:38 +0100 > Subject: Re: [Tutor] need idea > To: invincible_patriot at hotmail.com > CC: tutor at python.org > > On Wed, Feb 10, 2010 at 10:27 PM, invincible patriot > wrote: > > hi > > i want to compare a string with a dictionary > > or u can say that i want to take user input A STRING, and want to compare > > each character of that string with the KEYS in the dictionary, and then i > > wana print the values for the characters that are present in that strinng > > that we got as the input and were present in the dictionary as well > > > > can you please give me some idea how to do that > > > > what i hav done is that > > 1) I have made a dictionary with the keys and the values > > 2) I have taken the input from the user and hav saved it into a variable > > > > not i wana compare string that was given to us and replace them with the > > values given in the dictionary > > It's not yet completely clear to me what you want, but the following > should help you: > > Let str be the string, and dict the dictionary, then: > > [c for c in str if c in dict] > > will give you the characters in the string that are keys in the dictionary. > > > > > -- > Andr? Engels, andreengels at gmail.com _________________________________________________________________ Hotmail: Powerful Free email with security by Microsoft. http://clk.atdmt.com/GBL/go/201469230/direct/01/ -------------- next part -------------- An HTML attachment was scrubbed... URL: From andreengels at gmail.com Thu Feb 11 00:24:10 2010 From: andreengels at gmail.com (Andre Engels) Date: Thu, 11 Feb 2010 00:24:10 +0100 Subject: [Tutor] need idea In-Reply-To: References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> <1265831670.8722.18.camel@dedal-laptop> <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> <1265833607.8722.24.camel@dedal-laptop> <6faf39c91002101410w4ff0169cof846d70fc801fff5@mail.gmail.com> Message-ID: <6faf39c91002101524vf088331if8f5be3a3cd87304@mail.gmail.com> On Thu, Feb 11, 2010 at 12:12 AM, invincible patriot wrote: > thanks > let me clear you that what i am trying to do > suppose we hav a input string and a dict > our_dict={'a':'u', 't':'a', 'c':'g', 'g':'c'} > input_string='atcg' > > > now what i wana do is that where ever we are having 'a' i wana replace it > with 'u', 't' with 'a' and so on > i tried using input_string.replace('a', 'u') > but it is replacing only one character > i wana replace these 4 characters according to the dictionary > > i hope it is now clear > > kindly let me know how to proceed now See http://www.tutorialspoint.com/python/string_translate.htm -- Andr? Engels, andreengels at gmail.com From fubarninja at hotmail.com Thu Feb 11 00:43:31 2010 From: fubarninja at hotmail.com (jim serson) Date: Wed, 10 Feb 2010 18:43:31 -0500 Subject: [Tutor] running split and count + looping to check for numbers in same line Message-ID: I am getting an error when I try and run split and count I seem to get it to work with one or the other but not together. python wants a character buffer but I am not sure how to use it. I would also like to use readline to check and see if several numbers are in the same line but I think I will need to use it in a loop maybe for? So it would check for the first then check for the second if both are true add to count but if ether are false continue to next line and repeat. If anyone can help me that would be grate. Thanks look_in = "keno_back_up.txt"#raw_input ("Enter the search file to look in ") search = raw_input ("Enter your search item ").split file = open(look_in, "r").read().count(search) print "Your search came",file ,"times" Traceback (most recent call last): File "C:\Python26\keno program\get rid of 4", line 4, in file = open(look_in, "r").read().count(search) TypeError: expected a character buffer object _________________________________________________________________ -------------- next part -------------- An HTML attachment was scrubbed... URL: From transmogribenno at gmail.com Thu Feb 11 01:28:48 2010 From: transmogribenno at gmail.com (Benno Lang) Date: Thu, 11 Feb 2010 09:28:48 +0900 Subject: [Tutor] html and python In-Reply-To: <1265833607.8722.24.camel@dedal-laptop> References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> <1265831670.8722.18.camel@dedal-laptop> <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> <1265833607.8722.24.camel@dedal-laptop> Message-ID: <9b00d1a91002101628v11ba3349y288dde8593be42ed@mail.gmail.com> On Thu, Feb 11, 2010 at 5:26 AM, Grigor Kolev wrote: > I apologize to my question is incorrectly set. > We have a mail list and we want to do in site a list of all participants > with their photos and names. > List with people is saved in the txt file. > I want to open this file. Take all mail address and to do formating the > data. > Then with loop to do parsing all data and to do send in the html. > I can open and save as plain text document. > File = file(r'/home/user/test.html', 'w') > But if I refresh the data every day it by a ?slowly. If you can call scripts when actions occur on the mailing list (e.g. new subscriber added, user unsubscribes, user details updated, etc), then you could write a Python script to generate static HTML at that point. It would probably be less hassle than creating a dynamic web page. So then all you have to do is loop through your records and write the resultant HTML to a file that the web server can read. HTH, benno From dwbarne at earthlink.net Thu Feb 11 01:48:31 2010 From: dwbarne at earthlink.net (dwbarne at earthlink.net) Date: Wed, 10 Feb 2010 19:48:31 -0500 (EST) Subject: [Tutor] packing up python code to transfer to another machine Message-ID: <7228665.1265849311452.JavaMail.root@elwamui-norfolk.atl.sa.earthlink.net> I have become a true Pythonaholic. My newest problem is.... I have a rather large Python code (1.5yrs + developing!) currently running on Windows machines that imports several modules, some from external libraries. It allows the user to easily access MySQL databases and plot selected columns and such. I would like to bundle my (code + libraries + modules) and transfer all to a *nix environment, rather than just transferring my code over and then having to download and install all the relevant libraries again. Is this possible? I would think so with Python but am not sure. Is there a Python package that does this? If so, what? Thanks in advance. From kent37 at tds.net Thu Feb 11 03:50:53 2010 From: kent37 at tds.net (Kent Johnson) Date: Wed, 10 Feb 2010 21:50:53 -0500 Subject: [Tutor] running split and count + looping to check for numbers in same line In-Reply-To: References: Message-ID: <1c2a2c591002101850n3adebd2chf2bae4639584c6f3@mail.gmail.com> On Wed, Feb 10, 2010 at 6:43 PM, jim serson wrote: > I?am getting an error when I try and run split and count I seem to get it to > work with one or the other but not together. python wants a character buffer > but I am not sure how to use it. > > I would also like to use readline to check and see if several numbers are in > the same line but I think I will need to use it in a loop maybe for? So it > would check for the first then check for the second if both are true add to > count but if ether are false continue to next line and repeat. > > If anyone can help me that would be grate. > Thanks > > look_in = "keno_back_up.txt"#raw_input ("Enter the search file to look in ") > search = raw_input ("Enter your search item ").split Here search is actually a function because you left out the parentheses after split(). But with them, search would be a list. The argument to count() must be a string. > file = open(look_in, "r").read().count(search) > print "Your search came",file ,"times" Do you want a count per line or for the whole file? For the whole file you could do something like search_terms = raw_input ("Enter your search item ").split() # Note the final () data = open(look_in).read() count = 0 for term in search_terms: count += data.count(term) The last three lines could also be written as count = sum(data.count(term) for term in search_terms) Kent From fubarninja at hotmail.com Thu Feb 11 04:10:03 2010 From: fubarninja at hotmail.com (jim serson) Date: Wed, 10 Feb 2010 22:10:03 -0500 Subject: [Tutor] running split and count + looping to check for numbers in same line In-Reply-To: <1c2a2c591002101850n3adebd2chf2bae4639584c6f3@mail.gmail.com> References: , <1c2a2c591002101850n3adebd2chf2bae4639584c6f3@mail.gmail.com> Message-ID: Thanks for the information > Date: Wed, 10 Feb 2010 21:50:53 -0500 > Subject: Re: [Tutor] running split and count + looping to check for numbers in same line > From: kent37 at tds.net > To: fubarninja at hotmail.com > CC: tutor at python.org > > On Wed, Feb 10, 2010 at 6:43 PM, jim serson wrote: > > I am getting an error when I try and run split and count I seem to get it to > > work with one or the other but not together. python wants a character buffer > > but I am not sure how to use it. > > > > I would also like to use readline to check and see if several numbers are in > > the same line but I think I will need to use it in a loop maybe for? So it > > would check for the first then check for the second if both are true add to > > count but if ether are false continue to next line and repeat. > > > > If anyone can help me that would be grate. > > Thanks > > > > look_in = "keno_back_up.txt"#raw_input ("Enter the search file to look in ") > > search = raw_input ("Enter your search item ").split > > Here search is actually a function because you left out the > parentheses after split(). But with them, search would be a list. The > argument to count() must be a string. > > file = open(look_in, "r").read().count(search) > > print "Your search came",file ,"times" > > Do you want a count per line or for the whole file? For the whole file > you could do something like > > search_terms = raw_input ("Enter your search item ").split() # Note > the final () > data = open(look_in).read() > count = 0 > for term in search_terms: > count += data.count(term) > > The last three lines could also be written as > count = sum(data.count(term) for term in search_terms) > > Kent _________________________________________________________________ Check your Hotmail from your phone. http://go.microsoft.com/?linkid=9708121 -------------- next part -------------- An HTML attachment was scrubbed... URL: From dananzoff at gmail.com Thu Feb 11 04:39:13 2010 From: dananzoff at gmail.com (Harya Dananjaya) Date: Thu, 11 Feb 2010 12:39:13 +0900 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <333efb451002101147t648f1fcfk2c62501014a00dba@mail.gmail.com> References: <4B730BB8.1030004@gmail.com> <333efb451002101147t648f1fcfk2c62501014a00dba@mail.gmail.com> Message-ID: <4B737BE1.6040407@gmail.com> On 11/02/10 04:47, Wayne Werner wrote: > Do you mean a windows executable? Not really. Why do you want an .exe > anyway? Python code is (usually) cross-platform. > > -Wayne Yupe, Yupe, python is cross platform, but we need install python in every computer we want to using the pyththon *.py . Harya Dananjaya From dananzoff at gmail.com Thu Feb 11 04:53:13 2010 From: dananzoff at gmail.com (Harya Dananjaya) Date: Thu, 11 Feb 2010 12:53:13 +0900 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <1e53c511002101149y4197a86apf3a41c305bccd1be@mail.gmail.com> References: <4B730BB8.1030004@gmail.com> <1e53c511002101149y4197a86apf3a41c305bccd1be@mail.gmail.com> Message-ID: <4B737F29.9090303@gmail.com> On 11/02/10 04:49, vince spicer wrote: > > 1. Ubuntu and linux in general don't use exe per say > 2. Python can be compiled but not usually in the way you are thinking > 3. you might check out http://pypi.python.org/pypi/bbfreeze/ > Vince 1.Yupe, I know ubuntu don't use exe file. I have windows too, but windows is slower than ubuntu, so that's waste my time. 2. what do you mean about 'not usually in the way you thingking'? 3. OK, I have downloaded bbfreeze on my windows, but I can't install it on windows, I use 'easy_install bbfreeze' command, but generate some error Then I use c_freeze, but when I compile with cx_freeze, it generate error : ---------------------------------------Begin error-------------------------------------------------------------------------------------------------------------- Missing modules: ? Image imported from matplotlib.image ? PyQt4.QtGui imported from matplotlib.pyplot ? _scproxy imported from urllib ? _transforms imported from matplotlib.dates ? _wxagg imported from matplotlib.backends.backend_wxagg ? config imported from matplotlib ? gobject imported from matplotlib.pyplot ? mpl_toolkits.natgrid imported from matplotlib.mlab ? nose imported from numpy.testing.nosetester ? numpy.core.integer imported from numpy.fft.helper ? numpy.core.signbit imported from numpy.testing.utils ? pkg_resources imported from pytz ? pyemf imported from matplotlib.backends.backend_emf ? pytz.zoneinfo imported from matplotlib.dates ? qt imported from matplotlib.pyplot ? scipy imported from numpy.testing.nosetester ? win32pdh imported from numpy.testing.utils ------------------------------END of Error------------------------------------------------------------------------------------------------------------------- Harya Dananjaya From dananzoff at gmail.com Thu Feb 11 04:54:51 2010 From: dananzoff at gmail.com (Harya Dananjaya) Date: Thu, 11 Feb 2010 12:54:51 +0900 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <1265831819.8722.22.camel@dedal-laptop> References: <4B730BB8.1030004@gmail.com> <1265831819.8722.22.camel@dedal-laptop> Message-ID: <4B737F8B.3040008@gmail.com> On 11/02/10 04:56, Grigor Kolev wrote: > Use cx_freeze but you cannot make exe in ubuntu must use Windows OK, I have installed cx_freeze on my windows, but when I compile with cx_freeze, it generate error : ---------------------------------------Begin error-------------------------------------------------------------------------------------------------------------- Missing modules: ? Image imported from matplotlib.image ? PyQt4.QtGui imported from matplotlib.pyplot ? _scproxy imported from urllib ? _transforms imported from matplotlib.dates ? _wxagg imported from matplotlib.backends.backend_wxagg ? config imported from matplotlib ? gobject imported from matplotlib.pyplot ? mpl_toolkits.natgrid imported from matplotlib.mlab ? nose imported from numpy.testing.nosetester ? numpy.core.integer imported from numpy.fft.helper ? numpy.core.signbit imported from numpy.testing.utils ? pkg_resources imported from pytz ? pyemf imported from matplotlib.backends.backend_emf ? pytz.zoneinfo imported from matplotlib.dates ? qt imported from matplotlib.pyplot ? scipy imported from numpy.testing.nosetester ? win32pdh imported from numpy.testing.utils ------------------------------END of Error------------------------------------------------------------------------------------------------------------------- Harya Dananjaya From cfuller084 at thinkingplanet.net Thu Feb 11 04:53:23 2010 From: cfuller084 at thinkingplanet.net (Chris Fuller) Date: Wed, 10 Feb 2010 21:53:23 -0600 Subject: [Tutor] packing up python code to transfer to another machine In-Reply-To: <7228665.1265849311452.JavaMail.root@elwamui-norfolk.atl.sa.earthlink.net> References: <7228665.1265849311452.JavaMail.root@elwamui-norfolk.atl.sa.earthlink.net> Message-ID: <201002102153.23382.cfuller084@thinkingplanet.net> There are two obvious "gotchas". One is binary extensions. If you are using modules that are not "pure Python", you will have to find *nux versions for your target. The other problem is impossible to solve in general, but most of the time, it's less trouble than the first problem. Python is a dynamic language. Dependencies can be created at runtime (using __import__, exec, or execfile, at least), and it's certainly possible to write code that has unpredictable dependencies. Usually, however, the unknown dependency is drawn from a finite pool that is predictable. If you include all the bits that each third party modules comes with (and the same for your code, if it does any of these tricks), you should be Ok, but you can't prove it without analyzing the code. If you know the package dependencies (usually documented), you can work with that. matplotlib requires numpy, for instance. If this isn't enough, there's the modulefinder module. Note that it won't detect dynamic dependencies, so you have to know what third party stuff is included, and make sure you include all of it (or less, but only if you know what you're doing). Modulefinder also makes a lot of noise, and will include stuff you don't want or need. Another problem is platform compatibility. If you rely on the windows API, or filesystem idiosyncrasies, like drive letters, you'll have to fix those; but these are less surprising and easy to catch. Cheers On Wednesday 10 February 2010, dwbarne at earthlink.net wrote: > I have become a true Pythonaholic. My newest problem is.... > > I have a rather large Python code (1.5yrs + developing!) currently running > on Windows machines that imports several modules, some from external > libraries. It allows the user to easily access MySQL databases and plot > selected columns and such. > > I would like to bundle my (code + libraries + modules) and transfer all to > a *nix environment, rather than just transferring my code over and then > having to download and install all the relevant libraries again. > > Is this possible? I would think so with Python but am not sure. > > Is there a Python package that does this? If so, what? > > Thanks in advance. > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > From cfuller084 at thinkingplanet.net Thu Feb 11 05:18:50 2010 From: cfuller084 at thinkingplanet.net (Chris Fuller) Date: Wed, 10 Feb 2010 22:18:50 -0600 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <4B737F8B.3040008@gmail.com> References: <4B730BB8.1030004@gmail.com> <1265831819.8722.22.camel@dedal-laptop> <4B737F8B.3040008@gmail.com> Message-ID: <201002102218.50893.cfuller084@thinkingplanet.net> Using freeze or another tool of its ilk is only going to make you an executable for that platform. If you want an executable for a different platform, you need to set up a native Python environment with all the dependencies installed where Python can find them, and then use that platform's tools for making a standalone version. Cheers From simbobo at cooptel.net Wed Feb 10 17:57:01 2010 From: simbobo at cooptel.net (Owain Clarke) Date: Wed, 10 Feb 2010 16:57:01 +0000 Subject: [Tutor] string to list In-Reply-To: References: Message-ID: <4B72E55D.4080700@cooptel.net> With thanks to all who made suggestions, this was what I settled on f = open('testfile') #(testfile consisting of 2 columns of data, as per Kent's suggestion) data = [] for line in f: line_data = [int(x) for x in line.split()] data.append(line_data) data.sort(key=lambda x:x[0]) print "sort by first key:", data data.sort(key=lambda x:x[1]) print "sort by second key:", data I would love a really clear explanation of lambda! Owain From grigor.kolev at gmail.com Thu Feb 11 08:58:52 2010 From: grigor.kolev at gmail.com (=?windows-1251?B?w/Do4+7w?=) Date: Thu, 11 Feb 2010 09:58:52 +0200 Subject: [Tutor] html and python In-Reply-To: <9b00d1a91002101628v11ba3349y288dde8593be42ed@mail.gmail.com> References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> <1265831670.8722.18.camel@dedal-laptop> <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> <1265833607.8722.24.camel@dedal-laptop> <9b00d1a91002101628v11ba3349y288dde8593be42ed@mail.gmail.com> Message-ID: I found this. http://karrigell.sourceforge.net/en/pythoninsidehtml.htm 2010/2/11 Benno Lang : > On Thu, Feb 11, 2010 at 5:26 AM, Grigor Kolev wrote: >> I apologize to my question is incorrectly set. >> We have a mail list and we want to do in site a list of all participants >> with their photos and names. >> List with people is saved in the txt file. >> I want to open this file. Take all mail address and to do formating the >> data. >> Then with loop to do parsing all data and to do send in the html. >> I can open and save as plain text document. >> File = file(r'/home/user/test.html', 'w') >> But if I refresh the data every day it by a ?slowly. > > If you can call scripts when actions occur on the mailing list (e.g. > new subscriber added, user unsubscribes, user details updated, etc), > then you could write a Python script to generate static HTML at that > point. It would probably be less hassle than creating a dynamic web > page. > > So then all you have to do is loop through your records and write the > resultant HTML to a file that the web server can read. > > HTH, > benno > -- ????? ???? ???? ???, ???? ???? ??????? ?? ???? ?? ???? ! From alan.gauld at btinternet.com Thu Feb 11 09:29:43 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Thu, 11 Feb 2010 08:29:43 -0000 Subject: [Tutor] string to list References: <4B72E55D.4080700@cooptel.net> Message-ID: "Owain Clarke" wrote > I would love a really clear explanation of lambda! lambda returns an anonymous function - a function without a name. When we define a function normally we use something like: def square(x): return x*x That creates a function that has the name square We can do the same with lambda: square = lambda x : x*x which is equivalent to the def form. This is useful where we only need the function temporarily, such as to return a sort key or in building GUI controls. The general shape of lambda is: lambda : So in your case lambda x: x[0] could be replaced with def first(x): return x[0] lst.sort(key=first) But since you don't use first() for anything else you don't really need a named function so you can use a lambda. lambda is best used for short single line functions. In fact you can only use it where the body of the function can be expressed as a single expression. You will find more explanation and examples in the Functional Programming topic in my tutorial. HTH -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From alan.gauld at btinternet.com Thu Feb 11 09:34:19 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Thu, 11 Feb 2010 08:34:19 -0000 Subject: [Tutor] Compile py to exe in ubuntu References: <4B730BB8.1030004@gmail.com><333efb451002101147t648f1fcfk2c62501014a00dba@mail.gmail.com> <4B737BE1.6040407@gmail.com> Message-ID: "Harya Dananjaya" wrote >> Do you mean a windows executable? Not really. Why do you want an .exe >> anyway? Python code is (usually) cross-platform. > > Yupe, python is cross platform, but we need install python in every > computer we want to using the pyththon *.py . What would you do with Java? It too is cross platform but requires a JVM to be installed on every platform. Python is similar. The "compilers" actually bundle up the python interpreter with the script to create a large executable single file. But if you already have Python, or if you load several of these "exe"s it becomes very inefficient way to storing programs - multiple versions of Python. There can be cases where it makes sense but there are more cases where it malkes more sense to just install Python. IMHO -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From nikunjbadjatya at gmail.com Thu Feb 11 09:37:44 2010 From: nikunjbadjatya at gmail.com (nikunj badjatya) Date: Thu, 11 Feb 2010 14:07:44 +0530 Subject: [Tutor] "Error :Attempt to overwrite cell" while using xlwt to create excel sheets In-Reply-To: <1c2a2c591002100443i3fe03e45r2b57c69d83f5c037@mail.gmail.com> References: <1c2a2c591002100443i3fe03e45r2b57c69d83f5c037@mail.gmail.com> Message-ID: Hi, Many thanks to all.. I tried cell_overwrite=True and its working fine..!! On Wed, Feb 10, 2010 at 6:13 PM, Kent Johnson wrote: > On Wed, Feb 10, 2010 at 6:47 AM, nikunj badjatya > wrote: > > > I commented out the "raise Exception" statement in Row.py library > > module. > > Here's the (line no. 150 ) of Row.py which i have edited: > > > > def insert_cell(self, col_index, cell_obj): > > if col_index in self.__cells: > > if not self.__parent._cell_overwrite_ok: > > msg = "Attempt to overwrite cell: sheetname=%r rowx=%d > > colx=%d" \ > > % (self.__parent.name, self.__idx, col_index) > > #raise Exception(msg) > > #########*commented to avoid error. > > prev_cell_obj = self.__cells[col_index] > > sst_idx = getattr(prev_cell_obj, 'sst_idx', None) > > if sst_idx is not None: > > self.__parent_wb.del_str(sst_idx) > > self.__cells[col_index] = cell_obj > > > > The excel sheet creation code now works fine. > > > > My question is, Instead of manually goin to /usr/lib/.../row.py and > > commenting out the line, Can this be done through few lines of code in > > my program itself. ?? > > Looking at the code above, you can see that the exception is raised > only if self.__parent._cell_overwrite_ok is False. So there is an > option to allow overwriting. > > From the error message it appears that self.__parent is a Worksheet. > Looking at the source code for Worksheet.py, the __init__() method > does have an optional cell_overwrite_ok= parameter. This parameter is > also available in Workbook.add_sheet(). So if you pass > cell_overwrite=True to add_sheet() you should be OK. > > Kent > -------------- next part -------------- An HTML attachment was scrubbed... URL: From alan.plum at uni-koeln.de Thu Feb 11 09:41:40 2010 From: alan.plum at uni-koeln.de (Alan Plum) Date: Thu, 11 Feb 2010 09:41:40 +0100 Subject: [Tutor] string to list In-Reply-To: <4B72E55D.4080700@cooptel.net> References: <4B72E55D.4080700@cooptel.net> Message-ID: <1265877700.2935.17.camel@kallisti> On Mi, 2010-02-10 at 16:57 +0000, Owain Clarke wrote: > I would love a really clear explanation of lambda! Generally, lambdas are anonymous functions. In Python specifically, however, they are limited to simple expressions (i.e. only what you can put on the right-hand side of an assignment). myfunction = lambda : is roughly equivalent to: def myfunction(): return (note that the function definition becomes invalid if you leave out the function name, lambdas OTOH don't need to be assigned to a named variable and don't contain a name in their definition) The point here is that the expression is evaluated and the result returned by the lambda, much like the expression following a return statement in a normal function: the equivalent function's body consists of a single return statement with the lambda's body as return value. There's not much to understanding how lambdas work. They just make one-offs easier when all you really want to do is pass a value where a callable is required or if you want to do something like accessing an index or sub-index or member variable of each object in a list (which is what the sorting function's key argument is usually used for). In the case of your code, your lambda was: lambda x: x[0] and lambda x: x[1] If applied to a tuple or list, this works like this: >>> mytuple = ('a','b') >>> l1 = lambda x: x[0] >>> l2 = lambda x: x[1] >>> l1(mytuple) 'a' >>> l2(mytuple) 'b' Hope that helps. Alan Plum From timomlists at gmail.com Thu Feb 11 09:47:41 2010 From: timomlists at gmail.com (Timo) Date: Thu, 11 Feb 2010 09:47:41 +0100 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <4B730BB8.1030004@gmail.com> References: <4B730BB8.1030004@gmail.com> Message-ID: <4B73C42D.7090405@gmail.com> On 10-02-10 20:40, Harya Dananjaya wrote: > Can I compile my python source to exe in ubuntu? Like said before, you need Windows for this. > if I can do it, which compiler can do it? I use py2exe to compile my Python/PyGTK application. I build it on my Windows XP machine and it works on Windows 2000 to Windows 7 without installing anything else (like Python). Try GUI2exe for a nice graphical interface. Cheers, Timo > > Thanks you, > > Harya Dananjaya > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor From stefan_ml at behnel.de Thu Feb 11 10:44:08 2010 From: stefan_ml at behnel.de (Stefan Behnel) Date: Thu, 11 Feb 2010 10:44:08 +0100 Subject: [Tutor] string to list In-Reply-To: <4B72E55D.4080700@cooptel.net> References: <4B72E55D.4080700@cooptel.net> Message-ID: Owain Clarke, 10.02.2010 17:57: > data.sort(key=lambda x:x[0]) > data.sort(key=lambda x:x[1]) Two things to note: 1) you can use the operator module, specifically operator.itemgetter 2) given that you have lists as items in the 'data' list, it's enough to call sort() once, as the comparison of lists is defined as the comparison of each item to the corresponding item of the other list. If you want to sort based on the second item before the first item, it's best to exchange both items before sorting and swap them back afterwards. Stefan From laomao1975 at googlemail.com Thu Feb 11 10:56:51 2010 From: laomao1975 at googlemail.com (Lao Mao) Date: Thu, 11 Feb 2010 09:56:51 +0000 Subject: [Tutor] Simple Stats on Apache Logs Message-ID: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> Hi, I have 3 servers which generate about 2G of webserver logfiles in a day. These are available on my machine over NFS. I would like to draw up some stats which shows, for a given keyword, how many times it appears in the logs, per hour, over the previous week. So the behavior might be: $ ./webstats --keyword downloader Which would read from the logs (which it has access to) and produce something like: Monday: 0000: 12 0100: 17 etc I'm not sure how best to get started. My initial idea would be to filter the logs first, pulling out the lines with matching keywords, then check the timestamp - maybe incrementing a dictionary if the logfile was within a certain time? I'm not looking for people to write it for me, but I'd appreciate some guidance as the the approach and algorithm. Also what the simplest presentation model would be. Or even if it would make sense to stick it in a database! I'll post back my progress. Thanks, Laomao -------------- next part -------------- An HTML attachment was scrubbed... URL: From cwitts at compuscan.co.za Thu Feb 11 11:35:20 2010 From: cwitts at compuscan.co.za (Christian Witts) Date: Thu, 11 Feb 2010 12:35:20 +0200 Subject: [Tutor] Simple Stats on Apache Logs In-Reply-To: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> References: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> Message-ID: <4B73DD68.1090405@compuscan.co.za> Lao Mao wrote: > Hi, > > I have 3 servers which generate about 2G of webserver logfiles in a > day. These are available on my machine over NFS. > > I would like to draw up some stats which shows, for a given keyword, > how many times it appears in the logs, per hour, over the previous week. > > So the behavior might be: > > $ ./webstats --keyword downloader > > Which would read from the logs (which it has access to) and produce > something like: > > Monday: > 0000: 12 > 0100: 17 > > etc > > I'm not sure how best to get started. My initial idea would be to > filter the logs first, pulling out the lines with matching keywords, > then check the timestamp - maybe incrementing a dictionary if the > logfile was within a certain time? > > I'm not looking for people to write it for me, but I'd appreciate some > guidance as the the approach and algorithm. Also what the simplest > presentation model would be. Or even if it would make sense to stick > it in a database! I'll post back my progress. > > Thanks, > > Laomao > ------------------------------------------------------------------------ > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > grep -c

or if you are looking for only stuff for today for eg then grep | grep -c

That would be the simplest implementation. For a python implementation think about dictionaries with multiple layers like {Date: {Keyword1: Count, Keyword2: Count}. Essentially you would just iterate over the file, check if the line contains your keyword(s) that you are looking for and then incrementing the counter for it. -- Kind Regards, Christian Witts Business Intelligence C o m p u s c a n | Confidence in Credit Telephone: +27 21 888 6000 National Cell Centre: 0861 51 41 31 Fax: +27 21 413 2424 E-mail: cwitts at compuscan.co.za NOTE: This e-mail (including attachments )is subject to the disclaimer published at: http://www.compuscan.co.za/live/content.php?Item_ID=494. If you cannot access the disclaimer, request it from email.disclaimer at compuscan.co.za or 0861 514131. National Credit Regulator Credit Bureau Registration No. NCRCB6 From laomao1975 at googlemail.com Thu Feb 11 11:50:41 2010 From: laomao1975 at googlemail.com (Lao Mao) Date: Thu, 11 Feb 2010 10:50:41 +0000 Subject: [Tutor] Simple Stats on Apache Logs In-Reply-To: <4B73DD68.1090405@compuscan.co.za> References: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> <4B73DD68.1090405@compuscan.co.za> Message-ID: <9f92935c1002110250g7828748dk3dcbf72cdf3b4bee@mail.gmail.com> Hi Christian, grep -c

> or if you are looking for only stuff for today for eg then > grep | grep -c

> I don't see how that will produce figures per hour! That would be the simplest implementation. For a python implementation > think about dictionaries with multiple layers like {Date: {Keyword1: Count, > Keyword2: Count}. Essentially you would just iterate over the file, check > if the line contains your keyword(s) that you are looking for and then > incrementing the counter for it. > OK. Laomao -------------- next part -------------- An HTML attachment was scrubbed... URL: From denis.spir at free.fr Thu Feb 11 12:18:03 2010 From: denis.spir at free.fr (spir) Date: Thu, 11 Feb 2010 12:18:03 +0100 Subject: [Tutor] Simple Stats on Apache Logs In-Reply-To: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> References: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> Message-ID: <20100211121803.3532653b@o> On Thu, 11 Feb 2010 09:56:51 +0000 Lao Mao wrote: > Hi, > > I have 3 servers which generate about 2G of webserver logfiles in a day. > These are available on my machine over NFS. > > I would like to draw up some stats which shows, for a given keyword, how > many times it appears in the logs, per hour, over the previous week. > > So the behavior might be: > > $ ./webstats --keyword downloader > > Which would read from the logs (which it has access to) and produce > something like: > > Monday: > 0000: 12 > 0100: 17 > > etc > > I'm not sure how best to get started. My initial idea would be to filter > the logs first, pulling out the lines with matching keywords, then check the > timestamp - maybe incrementing a dictionary if the logfile was within a > certain time? > > I'm not looking for people to write it for me, but I'd appreciate some > guidance as the the approach and algorithm. Also what the simplest > presentation model would be. Or even if it would make sense to stick it in > a database! I'll post back my progress. As your logfile in rather big, I would iterate line per line using "for line in file". Check each line to determine whether (1) it has changed hour (2) it holds the given keyword. For the presentation, it depends on your expectation! Also, are keywords constants (= predefined at coding time)? You may think at a python (nested) dict: keywordStats = {} ... keywordStats[one_keyword] = { Monday: [12, 17, ...] , ... } (hours in 24 format (actually 0..23) are implicit keys of the lists) This lets open the opportunity to read the info back into the machine... Denis ________________________________ la vita e estrany http://spir.wikidot.com/ From sierra_mtnview at sbcglobal.net Thu Feb 11 12:38:51 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Thu, 11 Feb 2010 03:38:51 -0800 Subject: [Tutor] Exiting a Tkinter Program-- An Anomaly or two In-Reply-To: <4B721328.1090002@sbcglobal.net> References: <4B721328.1090002@sbcglobal.net> Message-ID: <4B73EC4B.9070902@sbcglobal.net> Well, I found where I had tucked away my inbox mail folder for tkinter. Somehow it got to be a subfolder of another list. It hadn't been used by me for months. The short of this is that I posted to tkinter, and have a better understanding of this now. In fact, fixed it by using sys.exit() in the def. On 2/9/2010 6:00 PM, Wayne Watson wrote: > I'm looking a 1800+ line someone else wrote. It uses one large dialog > for menus, and has a large area for images. A few menus open small > dialogs, for example, to enter a file name. The File menu has an exit > choice. The only other exit is the x in the upper right corner of the > large dialog. I'm pretty sure that menu is coded to quit via a shoft > def in the program. > > def Quit(self) > self.running = False > self.master.quit() > > I see no other code to quit. If I use Exit, the program does not > quite. If I then use the x, it quits and the shell script is left open > for a command. Any ideas why Quit doesn't work? It's accessible via a > self.mainMenu.add_command(.. command=self.Quit) > I had not turned the program loose by using a menu or touching any > controls. > > If I cause the program to print to the shell, and then use x to exit > that it hangs the shell. Why? When I x the shell, it tells me the > prog is running. Do I want to kill it. Yes,kills the shell window. > > The above seem abnormal to me. Comments? > -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From dananzoff at gmail.com Thu Feb 11 12:44:48 2010 From: dananzoff at gmail.com (Harya Dananjaya) Date: Thu, 11 Feb 2010 20:44:48 +0900 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: References: <4B730BB8.1030004@gmail.com><333efb451002101147t648f1fcfk2c62501014a00dba@mail.gmail.com> <4B737BE1.6040407@gmail.com> Message-ID: <4B73EDB0.6060602@gmail.com> On 11/02/10 17:34, Alan Gauld wrote: > > What would you do with Java? It too is cross platform but requires a > JVM to be installed on every platform. Python is similar. > OK, but python need 3rd praties library, and may be the the user don't know about the 3rd party libraries, and don't know how to install it on his computer. And not all person is programmer, so he don't want to know about programming, he just want to use the program. Harya Dananjaya From andreas at kostyrka.org Thu Feb 11 13:02:07 2010 From: andreas at kostyrka.org (Andreas Kostyrka) Date: Thu, 11 Feb 2010 13:02:07 +0100 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <4B73EDB0.6060602@gmail.com> References: <4B730BB8.1030004@gmail.com> <4B73EDB0.6060602@gmail.com> Message-ID: <201002111302.07899.andreas@kostyrka.org> Am Donnerstag, 11. Februar 2010 12:44:48 schrieb Harya Dananjaya: > On 11/02/10 17:34, Alan Gauld wrote: > > What would you do with Java? It too is cross platform but requires a > > JVM to be installed on every platform. Python is similar. > > OK, but python need 3rd praties library, and may be the the user don't > know about the 3rd party libraries, and don't know how to install it on > his computer. And not all person is programmer, so he don't want to know > about programming, he just want to use the program. Well, compiling it to a binary would not solve the problem. 1.) either you dynamically link the libraries. Then the user needs to have these installed. 2.) or you statically link the libraries. Then you get the same problem, slightly different: While the libraries are in the binary (which is a bad thing for many reasons, e.g. security fixes do not get applied this way), you can still have an environment mismatch, e.g. if your library expects services, file paths, and so on. The correct way to package a Linux program is to create a package for the distributions you want to support, and provide the source code and a README for all others. This way you can support users that are computer illiterate by making the package system ensure that all dependencies are available (and you can customize your app for the distribution if needed), and computer literate people can just read your README. If installing a package is to complicated for your target users, your only plausible strategy would be to make it a webapp, sorry. Andreas > > Harya Dananjaya > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > From kent37 at tds.net Thu Feb 11 14:13:53 2010 From: kent37 at tds.net (Kent Johnson) Date: Thu, 11 Feb 2010 08:13:53 -0500 Subject: [Tutor] html and python In-Reply-To: References: <1265830252.8722.1.camel@dedal-laptop> <1c2a2c591002101139q7106c729hc20d7731f783df29@mail.gmail.com> <1265831670.8722.18.camel@dedal-laptop> <1c2a2c591002101202h767b082fg8bdbfbd8dbd4d2ac@mail.gmail.com> <1265833607.8722.24.camel@dedal-laptop> <9b00d1a91002101628v11ba3349y288dde8593be42ed@mail.gmail.com> Message-ID: <1c2a2c591002110513l43195f8ct1017e2fbc8f89bfd@mail.gmail.com> 2010/2/11 ?????? : > I found this. > http://karrigell.sourceforge.net/en/pythoninsidehtml.htm Many options here: http://wiki.python.org/moin/Templating Kent From kent37 at tds.net Thu Feb 11 14:16:42 2010 From: kent37 at tds.net (Kent Johnson) Date: Thu, 11 Feb 2010 08:16:42 -0500 Subject: [Tutor] string to list In-Reply-To: References: <4B72E55D.4080700@cooptel.net> Message-ID: <1c2a2c591002110516v591093c6g65fda694ed3f21d@mail.gmail.com> On Thu, Feb 11, 2010 at 4:44 AM, Stefan Behnel wrote: > 2) given that you have lists as items in the 'data' list, it's enough to > call sort() once, as the comparison of lists is defined as the comparison > of each item to the corresponding item of the other list. If you want to > sort based on the second item before the first item, it's best to exchange > both items before sorting and swap them back afterwards. No, that is the old decorate-sort-undecorate idiom which has been replaced by the key= parameter to sort. data.sort(key=operator.itemgetter(1)) is the best way to sort on the second item. Kent From kent37 at tds.net Thu Feb 11 14:21:52 2010 From: kent37 at tds.net (Kent Johnson) Date: Thu, 11 Feb 2010 08:21:52 -0500 Subject: [Tutor] Simple Stats on Apache Logs In-Reply-To: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> References: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> Message-ID: <1c2a2c591002110521s35316e2fs4920558b5609f36b@mail.gmail.com> On Thu, Feb 11, 2010 at 4:56 AM, Lao Mao wrote: > Hi, > > I have 3 servers which generate about 2G of webserver logfiles in a day. > These are available on my machine over NFS. > > I would like to draw up some stats which shows, for a given keyword, how > many times it appears in the logs, per hour, over the previous week. > > So the behavior might be: > > $ ./webstats --keyword downloader > > Which would read from the logs (which it has access to) and produce > something like: > > Monday: > 0000: 12 > 0100: 17 > > etc > > I'm not sure how best to get started.? My initial idea would be to filter > the logs first, pulling out the lines with matching keywords, then check the > timestamp - maybe incrementing a dictionary if the logfile was within a > certain time? I would use itertools.groupby() to group lines by hour, then look for the keywords and increment a count. The technique of stacking generators as a processing pipeline might be useful. See David Beazley's "Generator Tricks for System Programmers" http://www.dabeaz.com/generators-uk/index.html Loghetti might also be useful as a starting point or code reference: http://code.google.com/p/loghetti/ Kent From stefan_ml at behnel.de Thu Feb 11 14:37:34 2010 From: stefan_ml at behnel.de (Stefan Behnel) Date: Thu, 11 Feb 2010 14:37:34 +0100 Subject: [Tutor] string to list In-Reply-To: <1c2a2c591002110516v591093c6g65fda694ed3f21d@mail.gmail.com> References: <4B72E55D.4080700@cooptel.net> <1c2a2c591002110516v591093c6g65fda694ed3f21d@mail.gmail.com> Message-ID: Kent Johnson, 11.02.2010 14:16: > On Thu, Feb 11, 2010 at 4:44 AM, Stefan Behnel wrote: > >> 2) given that you have lists as items in the 'data' list, it's enough to >> call sort() once, as the comparison of lists is defined as the comparison >> of each item to the corresponding item of the other list. If you want to >> sort based on the second item before the first item, it's best to exchange >> both items before sorting and swap them back afterwards. > > No, that is the old decorate-sort-undecorate idiom which has been > replaced by the key= parameter to sort. Nothing keeps you from writing data.sort(key=lambda x:x[::-1]) or data.sort(key=operator.itemgetter(slice(None,None,-1)) (which is equivalent) Stefan From kent37 at tds.net Thu Feb 11 15:11:30 2010 From: kent37 at tds.net (Kent Johnson) Date: Thu, 11 Feb 2010 09:11:30 -0500 Subject: [Tutor] string to list In-Reply-To: References: <4B72E55D.4080700@cooptel.net> <1c2a2c591002110516v591093c6g65fda694ed3f21d@mail.gmail.com> Message-ID: <1c2a2c591002110611r1dd2178eq643d99c9abda0e42@mail.gmail.com> On Thu, Feb 11, 2010 at 8:37 AM, Stefan Behnel wrote: > Kent Johnson, 11.02.2010 14:16: >> On Thu, Feb 11, 2010 at 4:44 AM, Stefan Behnel wrote: >> >>> 2) given that you have lists as items in the 'data' list, it's enough to >>> call sort() once, as the comparison of lists is defined as the comparison >>> of each item to the corresponding item of the other list. If you want to >>> sort based on the second item before the first item, it's best to exchange >>> both items before sorting and swap them back afterwards. >> >> No, that is the old decorate-sort-undecorate idiom which has been >> replaced by the key= parameter to sort. > > Nothing keeps you from writing > > ? ?data.sort(key=lambda x:x[::-1]) > > or > > ? ?data.sort(key=operator.itemgetter(slice(None,None,-1)) Ok, I thought you meant make a new list. These examples don't swap anything back... You can also use data.sort(key=operator.itemgetter(1, 0)) Kent From dananzoff at gmail.com Thu Feb 11 15:42:31 2010 From: dananzoff at gmail.com (Harya Dananjaya) Date: Thu, 11 Feb 2010 23:42:31 +0900 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <4B73C42D.7090405@gmail.com> References: <4B730BB8.1030004@gmail.com> <4B73C42D.7090405@gmail.com> Message-ID: <4B741757.4000008@gmail.com> On 11/02/10 17:47, Timo wrote: > I use py2exe to compile my Python/PyGTK application. > I build it on my Windows XP machine and it works on Windows 2000 to > Windows 7 without installing anything else (like Python). > > Try GUI2exe for a nice graphical interface. > > Cheers, > Timo > Yupe, I have a windows, after I using py2exe, the compilation is success, but when I run the *.exe, some error generated : Traceback (most recent call last): File "fondasi-4.py", line 16, in File "draw.pyc", line 5, in File "matplotlib\__init__.pyc", line 709, in File "matplotlib\__init__.pyc", line 627, in rc_params File "matplotlib\__init__.pyc", line 569, in matplotlib_fname File "matplotlib\__init__.pyc", line 240, in wrapper File "matplotlib\__init__.pyc", line 483, in _get_data_path_cached File "matplotlib\__init__.pyc", line 479, in _get_data_path RuntimeError: Could not find the matplotlib data files From andreas at kostyrka.org Thu Feb 11 15:57:32 2010 From: andreas at kostyrka.org (Andreas Kostyrka) Date: Thu, 11 Feb 2010 15:57:32 +0100 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <4B741757.4000008@gmail.com> References: <4B730BB8.1030004@gmail.com> <4B73C42D.7090405@gmail.com> <4B741757.4000008@gmail.com> Message-ID: <201002111557.33018.andreas@kostyrka.org> Am Donnerstag, 11. Februar 2010 15:42:31 schrieb Harya Dananjaya: > On 11/02/10 17:47, Timo wrote: > > I use py2exe to compile my Python/PyGTK application. > > I build it on my Windows XP machine and it works on Windows 2000 to > > Windows 7 without installing anything else (like Python). > > > > Try GUI2exe for a nice graphical interface. > > > > Cheers, > > Timo > > Yupe, I have a windows, > after I using py2exe, the compilation is success, > but when I run the *.exe, > some error generated : > RuntimeError: Could not find the matplotlib data files What's so hard? It's a plain text error message. So obviously (for people with at least two working brain cells, sorry could not resist), you need to include these too (or matplotlib will not work with py2exe, depending how it accesses these files I guess). So google searches that I'd consider: matplotlib py2exe py2exe including datafiles Andreas From dananzoff at gmail.com Thu Feb 11 16:21:43 2010 From: dananzoff at gmail.com (Harya Dananjaya) Date: Fri, 12 Feb 2010 00:21:43 +0900 Subject: [Tutor] Compile py to exe in ubuntu In-Reply-To: <201002111557.33018.andreas@kostyrka.org> References: <4B730BB8.1030004@gmail.com> <4B73C42D.7090405@gmail.com> <4B741757.4000008@gmail.com> <201002111557.33018.andreas@kostyrka.org> Message-ID: <4B742087.4080200@gmail.com> On 11/02/10 23:57, Andreas Kostyrka wrote: > What's so hard? It's a plain text error message. thank you,,, Now it's solved, I have include the needed library,,, It's solved, Thank you for all help me, Harya Dananjaya From randyeraymond at mchsi.com Thu Feb 11 17:09:38 2010 From: randyeraymond at mchsi.com (Randy Raymond) Date: Thu, 11 Feb 2010 10:09:38 -0600 Subject: [Tutor] Shelve Message-ID: I am running Python 2.6.4 under Windows Vista 32-bit Home Edition. When I run: import shelve test=shelve.open("myTest.fil") I get a DCPermissionerror exception. I am an administrator on this machine (it is my home PC). Python and Pythonw are both allowed exceptions to the Windows firewall. I tried turning the Windows Firewall completely off, but that does not help. Any ideas? Randy Raymond -------------- next part -------------- An HTML attachment was scrubbed... URL: From laomao1975 at googlemail.com Thu Feb 11 17:23:20 2010 From: laomao1975 at googlemail.com (Lao Mao) Date: Thu, 11 Feb 2010 16:23:20 +0000 Subject: [Tutor] Downloading S3 Logs Message-ID: <9f92935c1002110823g24033bf1qe742d63d6ff4062e@mail.gmail.com> Hello, I've written the below to get the previous day's logs from an Amazon S3 bucket. #!/usr/bin/python import time from datetime import datetime import boto daily_s3_log = open("/tmp/s3logs", "w+") now = datetime.now() connection = boto.connect_s3() bucket = connection.get_bucket("downloads.sekrit.co.uk") todays_keys = [] for key in bucket: time_difference = (now - datetime(*time.strptime(key.last_modified.split(".")[0], "%Y-%m-%dT%H: %M:%S")[0:6])).days if time_difference < 1 and key.name.startswith("log/access_log"): todays_keys.append(key) for key in todays_keys: key.get_file(daily_s3_log) daily_s3_log.close() This takes about 2 mins to download a day's logs (about 25M). I'd appreciate any improvements or feedback on the above. For example, would it make sense to make the first loop into a generator function that yields the interesting keys? Also is there a cleaner way to do the date comparison in Python 2.4? Thanks, Laomao -------------- next part -------------- An HTML attachment was scrubbed... URL: From randyeraymond at mchsi.com Thu Feb 11 17:54:14 2010 From: randyeraymond at mchsi.com (Randy Raymond) Date: Thu, 11 Feb 2010 10:54:14 -0600 Subject: [Tutor] Downloading S3 Logs In-Reply-To: <9f92935c1002110823g24033bf1qe742d63d6ff4062e@mail.gmail.com> References: <9f92935c1002110823g24033bf1qe742d63d6ff4062e@mail.gmail.com> Message-ID: <8F9AAEA0538346C2B328910CD4C7C27E@RandyPC> Mr. Mao, I am not a professional programmer. However, I do think that you want to reduce the number of "things" that you have to do in loops that go through the transaction (log entries in your case). Since you are converting to a datetime, perhaps rather than doing a calculation, you should remove the calculation and compare the datetime to yesterday (yesterday=now-1, whatever the datetime needs to make it yesterday) in the "if" statement (I.e. change "time_differnce < 1" to recordDate (<-make this instead of time_difference). You can try changing things a bit to see if it speeds up. For example, if a lot of messages are failing the "key.name.startswith("log/access_log")" test, then maybe make a nested if, testing "key.name.startswith("log/access_log")" before you actually test the date difference. Or, switch it around and test the date first, the the "key.name.startswith("log/access_log")". Sincerely, Randy Raymond From: Lao Mao Sent: Thursday, February 11, 2010 10:23 AM To: tutor at python.org Subject: [Tutor] Downloading S3 Logs Hello, I've written the below to get the previous day's logs from an Amazon S3 bucket. #!/usr/bin/python import time from datetime import datetime import boto daily_s3_log = open("/tmp/s3logs", "w+") now = datetime.now() connection = boto.connect_s3() bucket = connection.get_bucket("downloads.sekrit.co.uk") todays_keys = [] for key in bucket: time_difference = (now - datetime(*time.strptime(key.last_modified.split(".")[0], "%Y-%m-%dT%H: %M:%S")[0:6])).days if time_difference < 1 and key.name.startswith("log/access_log"): todays_keys.append(key) for key in todays_keys: key.get_file(daily_s3_log) daily_s3_log.close() This takes about 2 mins to download a day's logs (about 25M). I'd appreciate any improvements or feedback on the above. For example, would it make sense to make the first loop into a generator function that yields the interesting keys? Also is there a cleaner way to do the date comparison in Python 2.4? Thanks, Laomao -------------------------------------------------------------------------------- _______________________________________________ Tutor maillist - Tutor at python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor -------------- next part -------------- An HTML attachment was scrubbed... URL: From oberoc at gmail.com Thu Feb 11 18:09:20 2010 From: oberoc at gmail.com (Tino Dai) Date: Thu, 11 Feb 2010 12:09:20 -0500 Subject: [Tutor] Downloading S3 Logs In-Reply-To: <9f92935c1002110823g24033bf1qe742d63d6ff4062e@mail.gmail.com> References: <9f92935c1002110823g24033bf1qe742d63d6ff4062e@mail.gmail.com> Message-ID: <2ac5d4851002110909l1c45ba89s2b33ff513ba46a5b@mail.gmail.com> On Thu, Feb 11, 2010 at 11:23 AM, Lao Mao wrote: > Hello, > > I've written the below to get the previous day's logs from an Amazon S3 > bucket. > > #!/usr/bin/python > import time > from datetime import datetime > import boto > > daily_s3_log = open("/tmp/s3logs", "w+") > now = datetime.now() > connection = boto.connect_s3() > bucket = connection.get_bucket("downloads.sekrit.co.uk") > todays_keys = [] > > for key in bucket: > time_difference = (now - > datetime(*time.strptime(key.last_modified.split(".")[0], "%Y-%m-%dT%H: > %M:%S")[0:6])).days > if time_difference < 1 and key.name.startswith("log/access_log"): > todays_keys.append(key) > > for key in todays_keys: > key.get_file(daily_s3_log) > > daily_s3_log.close() > > This takes about 2 mins to download a day's logs (about 25M). > > What I would do would be to profile your code: You can find more profiling info @ http://docs.python.org/library/profile.html -Tino -------------- next part -------------- An HTML attachment was scrubbed... URL: From sander.sweers at gmail.com Thu Feb 11 18:15:40 2010 From: sander.sweers at gmail.com (Sander Sweers) Date: Thu, 11 Feb 2010 18:15:40 +0100 Subject: [Tutor] Shelve In-Reply-To: References: Message-ID: <1265908540.17394.11.camel@infirit> On do, 2010-02-11 at 10:09 -0600, Randy Raymond wrote: > I am running Python 2.6.4 under Windows Vista 32-bit Home Edition. > When I run: > > import shelve > test=shelve.open("myTest.fil") And to shich directory does this file get written? I suspect you are writing to a protected directory. When no path is given it will be written to the current directory, check with the os module where this is. import os, shelve print os.path.realpath(os.path.curdir) test=shelve.open("myTest.fil") Better is to always pass a full path like, 'C:\\Users\\ I get a DCPermissionerror exception. I am an administrator on this > machine (it is my home PC). Python and Pythonw are both allowed > exceptions to the Windows firewall. I tried turning the Windows > Firewall completely off, but that does not help. Any ideas? It is *always* helpful to provide the full error message. Greets Sander From randyeraymond at mchsi.com Thu Feb 11 17:22:17 2010 From: randyeraymond at mchsi.com (Randy Raymond) Date: Thu, 11 Feb 2010 10:22:17 -0600 Subject: [Tutor] Shelve In-Reply-To: References: Message-ID: <1A9DBDDEDBA945B6BBBDA8D467B0A825@RandyPC> Ok, I see that is was the directory restriction that was the problem. Sorry for the simple question. Randy Raymond From: Randy Raymond Sent: Thursday, February 11, 2010 10:09 AM To: Tutor Python Subject: [Tutor] Shelve I am running Python 2.6.4 under Windows Vista 32-bit Home Edition. When I run: import shelve test=shelve.open("myTest.fil") I get a DCPermissionerror exception. I am an administrator on this machine (it is my home PC). Python and Pythonw are both allowed exceptions to the Windows firewall. I tried turning the Windows Firewall completely off, but that does not help. Any ideas? Randy Raymond -------------------------------------------------------------------------------- _______________________________________________ Tutor maillist - Tutor at python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor -------------- next part -------------- An HTML attachment was scrubbed... URL: From gtxy37 at hotmail.com Thu Feb 11 19:59:54 2010 From: gtxy37 at hotmail.com (Matthew Matson) Date: Thu, 11 Feb 2010 13:59:54 -0500 Subject: [Tutor] Algorithm for combination analysis suggestion. Message-ID: Hi Tutors, I am looking for the proper approach regarding the analysis of a dictionary of combinations I have. What I need to do is read from a supplied text file that has a unique ID and that unique ID's associated combination of elements. So let's say I have the following lines in a text file (real file could be millions of lines): "ID" "Elements" 1 'A, B, C, D' 2 'A, D' 3 'D, E' 4 'A, D' 5 'A, B' 6 'A, C, D' and I do something like... combinationDict = {} for line in file: data = line.split('\t') comb = tuple(data[1].split(',')) if comb not in combinationDict: combinationDict[comb] = 1 else: combination[comb] +=1 Now after I read all of the data I end up with a dictionary with the combination as the key and the associated total qty as its value. print combinationDict {('A','B','C','D'):1, ('A','D'):2, ('D','E'):1, ('A','B'):1, ('A', 'C', 'D'):1} What I am looking for is a starting point for a solution in python to analyze the combination list so that I can determine for example that ('A', 'D') is the most popular combination and then determining how many other combinations in the dictionary contain this combination. I would like to incorporate some parameters so for example the combination ('A','B','C','D') and ('A', 'C', 'D') contain ('A','D') so they are valid but I could also say that as long as one element is contained in a combination it is valid as well provided I add no more than one additional item to the combination. If I apply this logic then ('D','E') can ('A','B') can contain ('A', 'D') and if I apply this to the combination dictionary I have: {('B','C', ('A', 'D')):1, ('A','D'):2, ('E', ('A', 'D')):1, ('B', ('A', 'D')):1, ('C', ('A', 'D')):1} which I could then query the keys for ('A', 'D') inclusion to get a total of 4 for ('A', 'D'). I hope this isn't too long and confusing but I am looking for an approach where I can analyze for the highest quantity of combinations and then iterate through the dictionary substituting those combinations that were determined a "highest qty" combination into other low qty combinations when valid. I was hoping to have parameters to qualify a high qty combination (e.g. every combination with qty above 10,000) with the highest quantity of that determined set taking precedence for substitution for the first pass then moving on to the next highest combination for the second pass of substitution etc.. The other parameter would be for the combination that would receive a substitution whereby I might say that I can only substitute if a substitution results in only one additional (superfluous) value being added to the combination existing low qty combination. I have looked around and this sounds like it might be similar to a packing problem and in particular the knapsack problem but I can't seem to wrap my head around an approach for this in python. I am not looking for a solution just some guidance on a starting point or perhaps libraries that may be helpful. Thank you. _________________________________________________________________ -------------- next part -------------- An HTML attachment was scrubbed... URL: From grigor.kolev at gmail.com Thu Feb 11 21:13:36 2010 From: grigor.kolev at gmail.com (Grigor Kolev) Date: Thu, 11 Feb 2010 22:13:36 +0200 Subject: [Tutor] SMTP Message-ID: <1265919216.8909.13.camel@dedal-laptop> Hi. I try send a mail with smtplib Server work with postfix. I try it ------------------------------------------------ import smtplib s=smtplib.SMTP("localhost") tolist=['grigor.kolev at gmail.com'] msg = '''\ From: grigor.kolev at gmail.com Subject: testin' This is a test ''' s.sendmail("test at local", tolist, msg) ------------------------------------------------- How can i send the file? And I am not sure that work. Mail is not sending but perhaps problem i in my postfix. -- Grigor Kolev From kent37 at tds.net Thu Feb 11 21:21:51 2010 From: kent37 at tds.net (Kent Johnson) Date: Thu, 11 Feb 2010 15:21:51 -0500 Subject: [Tutor] Algorithm for combination analysis suggestion. In-Reply-To: References: Message-ID: <1c2a2c591002111221g65f17639wa798118b5a71b6ff@mail.gmail.com> On Thu, Feb 11, 2010 at 1:59 PM, Matthew Matson wrote: > > Hi Tutors, > > I am looking for the proper approach regarding the analysis of a dictionary > of combinations I have. > > What I need to do is read from a supplied text file that has a unique ID and > that unique ID's associated combination of elements. So let's say I have the > following lines in a text file (real file could be millions of lines): > > "ID"??? "Elements" > 1??? 'A, B, C, D' > 2??? 'A, D' > 3??? 'D, E' > 4??? 'A, D' > 5??? 'A, B' > 6??? 'A, C, D' > > and I do something like... > > combinationDict = {} > for line in file: > ??? data = line.split('\t') > ??? comb = tuple(data[1].split(',')) > ??? if comb not in combinationDict: > ??? ??? combinationDict[comb] = 1 > ??? else: > ??? ??? combination[comb] +=1 Use combinationDict = collections.defaultdict(int) Then you can just write combination[comb] += 1 without the test for comb in combinattionDict. > Now after I read all of the data I end up with a dictionary with the > combination as the key and the associated total qty as its value. > > print combinationDict > {('A','B','C','D'):1, ('A','D'):2, ('D','E'):1, ('A','B'):1, ('A', 'C', > 'D'):1} > > What I am looking for is a starting point for a solution in python to > analyze the combination list so that I can determine for example that ('A', > 'D') is the most popular combination and then determining how many other > combinations in the dictionary contain this combination. maxComb = max(combinationDict, key=combinationDict.__getitem__) will give you the single key with the largest count. maxCombSet = set(maxComb) [ comb for comb in combinationDict if maxCombSet <= set(comb) ] will give you a list of all the combinations that contain the max though it could be slow if you have lots of unique combinations (because of all the set conversions). > I would like to incorporate some parameters so for example the combination > ('A','B','C','D') and ('A', 'C', 'D') contain ('A','D') so they are valid > but I could also say that as long as one element is contained in a > combination it is valid as well provided I add no more than one additional > item to the combination. Now you are starting to lose me but you can modify the conditional in the above list comprehension to make whatever kind of test you want. > If I apply this logic then ('D','E') can ('A','B') > can contain ('A', 'D') and if I apply this to the combination dictionary I > have: > > {('B','C', ('A', 'D')):1, ('A','D'):2, ('E', ('A', 'D')):1, ('B', ('A', > 'D')):1, ('C', ('A', 'D')):1} > > which I could then query the keys for ('A', 'D') inclusion to get a total of > 4 for ('A', 'D'). Now you have lost me completely. What are the keys in this new dict? How do you get a total of 4 fro ('A', 'D')? Kent > I hope this isn't too long and confusing but I am looking for an approach > where I can analyze for the highest quantity of combinations and then > iterate through the dictionary substituting those combinations that were > determined a "highest qty" combination into other low qty combinations when > valid. > > I was hoping to have parameters to qualify a high qty combination (e.g. > every combination with qty above 10,000) with the highest quantity of that > determined set taking precedence for substitution for the first pass then > moving on to the next highest combination for the second pass of > substitution etc.. The other parameter would be for the combination that > would receive a substitution whereby I might say that I can only substitute > if a substitution results in only one additional (superfluous) value being > added to the combination existing low qty combination. > > I have looked around and this sounds like it might be similar to a packing > problem and in particular the knapsack problem but I can't seem to wrap my > head around an approach for this in python. I am not looking for a solution > just some guidance on a starting point or perhaps libraries that may be > helpful. > > Thank you. > > > ________________________________ > Windows? phone-your Windows stuff, on the go. See more. > _______________________________________________ > Tutor maillist ?- ?Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > > From kent37 at tds.net Thu Feb 11 22:04:31 2010 From: kent37 at tds.net (Kent Johnson) Date: Thu, 11 Feb 2010 16:04:31 -0500 Subject: [Tutor] SMTP In-Reply-To: <1265919216.8909.13.camel@dedal-laptop> References: <1265919216.8909.13.camel@dedal-laptop> Message-ID: <1c2a2c591002111304y13730a1ahe13ccd8c011e5268@mail.gmail.com> On Thu, Feb 11, 2010 at 3:13 PM, Grigor Kolev wrote: > Hi. > I try send a mail with smtplib > Server work with postfix. > I try it > ------------------------------------------------ > ?import smtplib > ?s=smtplib.SMTP("localhost") > tolist=['grigor.kolev at gmail.com'] > msg = '''\ > ?From: grigor.kolev at gmail.com > Subject: testin' > This is a test ''' > s.sendmail("test at local", tolist, msg) > ------------------------------------------------- > How can i send the file? I think you need the To: header in the msg, and possibly a blank line after the headers. See the example here: http://docs.python.org/library/smtplib.html#smtp-example Kent From alan.gauld at btinternet.com Thu Feb 11 23:00:58 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Thu, 11 Feb 2010 22:00:58 -0000 Subject: [Tutor] Compile py to exe in ubuntu References: <4B730BB8.1030004@gmail.com><333efb451002101147t648f1fcfk2c62501014a00dba@mail.gmail.com> <4B737BE1.6040407@gmail.com> <4B73EDB0.6060602@gmail.com> Message-ID: "Harya Dananjaya" wrote >> What would you do with Java? It too is cross platform but requires a >> JVM to be installed on every platform. Python is similar. >> > OK, but python need 3rd praties library, No, you can write very sophisticated Python apps using just the standard library. Equally many Java apps require 3rd party libraries. There really is no difference between the two. > and may be the the user don't know about the 3rd party libraries, > and don't know how to install it on his computer. But you can wrte an installer that installs the 3rd party libraries without compiling the script to an 'exe'. And may 'exe's require third party libraries - especially on Windows where installing an exe along with a bunch of DLLs is normal. > And not all person is programmer, so he don't want to know > about programming, he just want to use the program. They shouldn't need to know about prrogramming to run an installer. I think you are confusing an install program with a compiler. A good installer will check that Python is installed (and that it is the minimum version), install the scripts needed (including modules), install any third party libraries as needed (in other words check to see if you can find them first) and add things like help files and readme documents. Finally it should offer to place an icon/entry in the start menu or desktop or where-ever is normal for the OS. But none of that requires the application to be an executable. -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From alan.gauld at btinternet.com Thu Feb 11 23:09:35 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Thu, 11 Feb 2010 22:09:35 -0000 Subject: [Tutor] SMTP References: <1265919216.8909.13.camel@dedal-laptop> Message-ID: "Grigor Kolev" wrote > I try send a mail with smtplib > Server work with postfix. > I try it > ------------------------------------------------ > import smtplib > s=smtplib.SMTP("localhost") This requires you to have an SMTP server running on localhost. Do you? I notice you say the server works with postfix but is it running when you exercise the script? Its one possibility. > tolist=['grigor.kolev at gmail.com'] > msg = '''\ > From: grigor.kolev at gmail.com > Subject: testin' > This is a test ''' > s.sendmail("test at local", tolist, msg) > ------------------------------------------------- > How can i send the file? > And I am not sure that work. > Mail is not sending but perhaps problem i in my postfix. HTH, Alan G From gtxy37 at hotmail.com Thu Feb 11 23:34:31 2010 From: gtxy37 at hotmail.com (Matthew Matson) Date: Thu, 11 Feb 2010 17:34:31 -0500 Subject: [Tutor] Algorithm for combination analysis suggestion. In-Reply-To: <1c2a2c591002111221g65f17639wa798118b5a71b6ff@mail.gmail.com> References: , <1c2a2c591002111221g65f17639wa798118b5a71b6ff@mail.gmail.com> Message-ID: Thanks Kent. I know this is confusing, perhaps if we look at it this way. Let's say A,B,C,D,E are widgets that I manufacture, now the easiest way for me to distribute them to the the unique IDs would be to gather all the widget quantities from the complete list of combinations. In this case I would need to 5 A's, 2 B's, 2 C's, 5 D's, and 1 E and assemble all of the unique IDs distributions in assembly. Putting the widgets together in assembly is expensive so I have the oppotunity in manufacturing to produce combined widgets (e.g. ('A', 'D')). The more combined widgets that I can produce in manufacturing equates to less gathering of individual widgets in assembly reducing time and cost. Because of manufacturing setup I need a significant volume of a combined widget in order to produce cost effectively hence the minimum qty threshold for that combined widget. If I have a combined widget in the combination list with a large volume we are manufacturing anyway I can just add additional qty to this at minimal cost so what I want to do is analyze all my combinations and add as many combined widgets to them as possible. If I have a combination that requires only one item from a combined widget I can add this to the combination provided that by adding this combined widget to the combination I do not add any more than one not required additonal widget to the original combination. I think this still sounds confusing - I will see if I can code up a sample of what I am trying to do. Thanks again. > Date: Thu, 11 Feb 2010 15:21:51 -0500 > Subject: Re: [Tutor] Algorithm for combination analysis suggestion. > From: kent37 at tds.net > To: gtxy37 at hotmail.com > CC: tutor at python.org > > On Thu, Feb 11, 2010 at 1:59 PM, Matthew Matson wrote: > > > > Hi Tutors, > > > > I am looking for the proper approach regarding the analysis of a dictionary > > of combinations I have. > > > > What I need to do is read from a supplied text file that has a unique ID and > > that unique ID's associated combination of elements. So let's say I have the > > following lines in a text file (real file could be millions of lines): > > > > "ID" "Elements" > > 1 'A, B, C, D' > > 2 'A, D' > > 3 'D, E' > > 4 'A, D' > > 5 'A, B' > > 6 'A, C, D' > > > > and I do something like... > > > > combinationDict = {} > > for line in file: > > data = line.split('\t') > > comb = tuple(data[1].split(',')) > > if comb not in combinationDict: > > combinationDict[comb] = 1 > > else: > > combination[comb] +=1 > > Use > combinationDict = collections.defaultdict(int) > > Then you can just write > combination[comb] += 1 > without the test for comb in combinattionDict. > > > Now after I read all of the data I end up with a dictionary with the > > combination as the key and the associated total qty as its value. > > > > print combinationDict > > {('A','B','C','D'):1, ('A','D'):2, ('D','E'):1, ('A','B'):1, ('A', 'C', > > 'D'):1} > > > > What I am looking for is a starting point for a solution in python to > > analyze the combination list so that I can determine for example that ('A', > > 'D') is the most popular combination and then determining how many other > > combinations in the dictionary contain this combination. > > maxComb = max(combinationDict, key=combinationDict.__getitem__) will > give you the single key with the largest count. > > maxCombSet = set(maxComb) > [ comb for comb in combinationDict if maxCombSet <= set(comb) ] > > will give you a list of all the combinations that contain the max > though it could be slow if you have lots of unique combinations > (because of all the set conversions). > > > I would like to incorporate some parameters so for example the combination > > ('A','B','C','D') and ('A', 'C', 'D') contain ('A','D') so they are valid > > but I could also say that as long as one element is contained in a > > combination it is valid as well provided I add no more than one additional > > item to the combination. > > Now you are starting to lose me but you can modify the conditional in > the above list comprehension to make whatever kind of test you want. > > > If I apply this logic then ('D','E') can ('A','B') > > can contain ('A', 'D') and if I apply this to the combination dictionary I > > have: > > > > {('B','C', ('A', 'D')):1, ('A','D'):2, ('E', ('A', 'D')):1, ('B', ('A', > > 'D')):1, ('C', ('A', 'D')):1} > > > > which I could then query the keys for ('A', 'D') inclusion to get a total of > > 4 for ('A', 'D'). > > Now you have lost me completely. What are the keys in this new dict? > How do you get a total of 4 fro ('A', 'D')? > > Kent > > > I hope this isn't too long and confusing but I am looking for an approach > > where I can analyze for the highest quantity of combinations and then > > iterate through the dictionary substituting those combinations that were > > determined a "highest qty" combination into other low qty combinations when > > valid. > > > > I was hoping to have parameters to qualify a high qty combination (e.g. > > every combination with qty above 10,000) with the highest quantity of that > > determined set taking precedence for substitution for the first pass then > > moving on to the next highest combination for the second pass of > > substitution etc.. The other parameter would be for the combination that > > would receive a substitution whereby I might say that I can only substitute > > if a substitution results in only one additional (superfluous) value being > > added to the combination existing low qty combination. > > > > I have looked around and this sounds like it might be similar to a packing > > problem and in particular the knapsack problem but I can't seem to wrap my > > head around an approach for this in python. I am not looking for a solution > > just some guidance on a starting point or perhaps libraries that may be > > helpful. > > > > Thank you. > > > > > > ________________________________ > > Windows? phone-your Windows stuff, on the go. See more. > > _______________________________________________ > > Tutor maillist - Tutor at python.org > > To unsubscribe or change subscription options: > > http://mail.python.org/mailman/listinfo/tutor > > > > _________________________________________________________________ Introducing Windows? phone. http://go.microsoft.com/?linkid=9708122 -------------- next part -------------- An HTML attachment was scrubbed... URL: From lawrence.jones at imperial.ac.uk Thu Feb 11 23:15:14 2010 From: lawrence.jones at imperial.ac.uk (Jones, Lawrence D) Date: Thu, 11 Feb 2010 22:15:14 +0000 Subject: [Tutor] Coin flip game Message-ID: <544ED9D63633B348ADA92AC334EC98081ED3A0BACA@ICEXM4.ic.ac.uk> Hi, I'm new to the list and to Python. I'm reading through Michael Dawson's 'Python programming: for absolute beginners' and at the end of chapter 3 he's set a challenge where the reader has to create a coin flip game. My code now works, but only after I randomly switched pieces of the code around and, basically, pulled my hair out because it wouldn't work. My code is below. But can someone please explain to me why the following variable has to be placed where it is for the code to work? I thought it would need to go nearer the start of the code i.e. just before heads = 0, tails = 0 etc: coin = random.randrange(2) Also, why does the randrange integer have to be '2'? I only discovered this worked by complete accident. I tried '1' and '0,1' as my integers but they just didn't work. Thanks, Lawrence import random print "The Coin Flip Game\n" heads = 0 tails = 0 count = 0 while count < 100: coin = random.randrange(2) if coin == 0: heads = heads + 1 else: tails = tails + 1 count += 1 print "Heads: ", heads print "Tails: ", tails raw_input("\nPress enter to exit.") -------------- next part -------------- An HTML attachment was scrubbed... URL: From transmogribenno at gmail.com Fri Feb 12 00:16:04 2010 From: transmogribenno at gmail.com (Benno Lang) Date: Fri, 12 Feb 2010 08:16:04 +0900 Subject: [Tutor] Coin flip game In-Reply-To: <544ED9D63633B348ADA92AC334EC98081ED3A0BACA@ICEXM4.ic.ac.uk> References: <544ED9D63633B348ADA92AC334EC98081ED3A0BACA@ICEXM4.ic.ac.uk> Message-ID: <9b00d1a91002111516hf8bfd43m766176d47ba5b93f@mail.gmail.com> On Fri, Feb 12, 2010 at 7:15 AM, Jones, Lawrence D wrote: > My code is below. But can someone please explain to me why the following > variable has to be placed where it is for the code to work? I thought it > would need to go nearer the start of the code i.e. just before heads = 0, > tails = 0 etc: > ??????????????? coin = random.randrange(2) If you put this at the start of the code (before the loop), then you only flip the coin once, and then count that single flip 100 times. That would work, but wouldn't be a very useful program. > Also, why does the randrange integer have to be ?2?? I only discovered this > worked by complete accident. I tried ?1? and ?0,1? as my integers but they > just didn?t work. See: http://docs.python.org/library/random.html#random.randrange random.randrange parameters are the same as for range, which you can learn more about here: http://docs.python.org/tutorial/controlflow.html#the-range-function HTH, benno From ldl08 at gmx.net Fri Feb 12 01:49:47 2010 From: ldl08 at gmx.net (David) Date: Fri, 12 Feb 2010 08:49:47 +0800 Subject: [Tutor] Coin flip game In-Reply-To: <544ED9D63633B348ADA92AC334EC98081ED3A0BACA@ICEXM4.ic.ac.uk> References: <544ED9D63633B348ADA92AC334EC98081ED3A0BACA@ICEXM4.ic.ac.uk> Message-ID: <4B74A5AB.8050406@gmx.net> Hello Lawrence, let me try to clarify this (warning: am a beginner myself). On 12/02/10 06:15, Jones, Lawrence D wrote: > Hi, > > I'm new to the list and to Python. I'm reading through Michael Dawson's 'Python programming: for absolute beginners' and at the end of chapter 3 he's set a challenge where the reader has to create a coin flip game. My code now works, but only after I randomly switched pieces of the code around and, basically, pulled my hair out because it wouldn't work. > > My code is below. But can someone please explain to me why the following variable has to be placed where it is for the code to work? I thought it would need to go nearer the start of the code i.e. just before heads = 0, tails = 0 etc: > > coin = random.randrange(2) Python runs through your code, step by step. I believe it starts at the top and goes down, following the logic of your code. When you make Python refer to a variable in your while loop that Python has not encountered yet, then it will not know what to do -- and complain about it. Solution: let Python know of the variable _before_ you then start to work with it. > > Also, why does the randrange integer have to be '2'? I only discovered this worked by complete accident. I tried '1' and '0,1' as my integers but they just didn't work. That is because your coin has _two_ sides, and you therefore want a random choice out of _two_ possibilities. With the random.randrange(2) function the choices will be 0 and 1, satisfying your demands. This means that the randrange() function goes up to, but not including, the integer you supply. It amounts to two choices in the end all the same because the counting starts with 0 instead of 1. That is, if you chose randrange(1) you will get only one answer, namely 0. If you type randrange(0) then you will get an error message (ValueError: empty range for randrange). Which makes sense. Remember, randrange() goes up to, but not including the integer supplied. HTH, David > > Thanks, > > Lawrence > > > import random > print "The Coin Flip Game\n" > > heads = 0 > tails = 0 > count = 0 > > while count< 100: > coin = random.randrange(2) > if coin == 0: > heads = heads + 1 > else: > tails = tails + 1 > count += 1 > > print "Heads: ", heads > print "Tails: ", tails > > raw_input("\nPress enter to exit.") > > > > > > > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor From alan.gauld at btinternet.com Fri Feb 12 02:04:26 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Fri, 12 Feb 2010 01:04:26 -0000 Subject: [Tutor] Coin flip game References: <544ED9D63633B348ADA92AC334EC98081ED3A0BACA@ICEXM4.ic.ac.uk> Message-ID: "Jones, Lawrence D" wrote > My code is below. But can someone please explain to me > why the following variable has to be placed where it is Others have explained about variable creation and the fact you need to be inside the loop to get different results for each iteration. coin = random.randrange(2) I just want to pick up on something you said. You asked about the "variable". The variable is "coin". It can go anywhere before the point of use, even the first line of your code. You could have done coin = None or coin = 0 and it would work just fine. What needs to be inside the loop is the call to the randrange() function. That is what is simulating the coin flip. So you need to distinguish the difference between variable creation (which in Python happens by means of the first assignment of a value) and function application (where you call a function and assign its return value to a variable.) In your code you create the variable coin at the same time as you apply the function, but you could have done those two things separately and the code would still work. It might seem like I'm splitting hairs but it starts to make a difference in some other cases, like this: while True: coin = coin + someFunction() This will raise an error because you are using the value of coin (on the right hand side) before it has been created. You need to write it like this: coin = 0 while True coin = coin + someFunction() It is very important in programming to be clear in your mind about these different concepts, especially when deciphering error messages. HTH, -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From jlintz at gmail.com Fri Feb 12 06:15:33 2010 From: jlintz at gmail.com (Justin Lintz) Date: Fri, 12 Feb 2010 00:15:33 -0500 Subject: [Tutor] Simple Stats on Apache Logs In-Reply-To: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> References: <9f92935c1002110156u5692bc48s4760413abd6f061b@mail.gmail.com> Message-ID: <99edfc5e1002112115t4f887756vd0b4fbc0e718d947@mail.gmail.com> On Thu, Feb 11, 2010 at 4:56 AM, Lao Mao wrote: > Hi, > > I have 3 servers which generate about 2G of webserver logfiles in a day. > These are available on my machine over NFS. > > I would like to draw up some stats which shows, for a given keyword, how > many times it appears in the logs, per hour, over the previous week. > > So the behavior might be: > > $ ./webstats --keyword downloader > > Which would read from the logs (which it has access to) and produce > something like: > > Monday: > 0000: 12 > 0100: 17 > > etc > > I'm not sure how best to get started.? My initial idea would be to filter > the logs first, pulling out the lines with matching keywords, then check the > timestamp - maybe incrementing a dictionary if the logfile was within a > certain time? > > I'm not looking for people to write it for me, but I'd appreciate some > guidance as the the approach and algorithm.? Also what the simplest > presentation model would be.? Or even if it would make sense to stick it in > a database!? I'll post back my progress. > > Thanks, > > Laomao > > _______________________________________________ > Tutor maillist ?- ?Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > > You may also find this link useful http://effbot.org/zone/wide-finder.htm on parsing logs efficiently using Python. From alan.gauld at btinternet.com Fri Feb 12 10:34:41 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Fri, 12 Feb 2010 09:34:41 -0000 Subject: [Tutor] New Python testing book Message-ID: Amazon have just brought to my attention the following title: Python Testing: Beginner's Guide Has anyone seen this? Is it any good? What test frameworks does it cover? Amazon are remarkably reticent about the actual contents. Its very new, only published on 22nd January. Alan G. From ldl08 at gmx.net Fri Feb 12 11:26:36 2010 From: ldl08 at gmx.net (David) Date: Fri, 12 Feb 2010 18:26:36 +0800 Subject: [Tutor] New Python testing book In-Reply-To: References: Message-ID: <4B752CDC.1060707@gmx.net> Hi Alan, On 12/02/10 17:34, Alan Gauld wrote: > Amazon are remarkably reticent about the actual contents. See here: http://tinyurl.com/y9dy62p I am, btw, always happy to see 'book announcements' on this list -- keep them coming! David From onyxtic at gmail.com Fri Feb 12 11:35:16 2010 From: onyxtic at gmail.com (Evans Anyokwu) Date: Fri, 12 Feb 2010 10:35:16 +0000 Subject: [Tutor] New Python testing book In-Reply-To: <4B752CDC.1060707@gmx.net> References: <4B752CDC.1060707@gmx.net> Message-ID: On Fri, Feb 12, 2010 at 10:26 AM, David wrote: > Hi Alan, > > > On 12/02/10 17:34, Alan Gauld wrote: > > Amazon are remarkably reticent about the actual contents. >> > See here: http://tinyurl.com/y9dy62p > > I am, btw, always happy to see 'book announcements' on this list -- keep > them coming! > > David For those who don't like shortened URL, here's the actual link http://www.packtpub.com/view_popup/page/python-testing-beginners-guide-table-of-contents It's just the Table of Content and nothing else. -- Evans > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > -------------- next part -------------- An HTML attachment was scrubbed... URL: From fomcl at yahoo.com Fri Feb 12 12:12:52 2010 From: fomcl at yahoo.com (Albert-Jan Roskam) Date: Fri, 12 Feb 2010 03:12:52 -0800 (PST) Subject: [Tutor] Coin flip game In-Reply-To: <4B74A5AB.8050406@gmx.net> Message-ID: <913294.57511.qm@web110716.mail.gq1.yahoo.com> Hi, random.choice offers an intuitive way to write the code: import random for i in range(10): ??? print random.choice(["head", "tail"]) Cheers!! Albert-Jan ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In the face of ambiguity, refuse the temptation to guess. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ --- On Fri, 2/12/10, David wrote: From: David Subject: Re: [Tutor] Coin flip game To: tutor at python.org Date: Friday, February 12, 2010, 1:49 AM Hello Lawrence, let me try to clarify this (warning: am a beginner myself). On 12/02/10 06:15, Jones, Lawrence D wrote: > Hi, > > I'm new to the list and to Python. I'm reading through Michael Dawson's 'Python programming: for absolute beginners' and at the end of chapter 3 he's set a challenge where the reader has to create a coin flip game. My code now works, but only after I randomly switched pieces of the code around and, basically, pulled my hair out because it wouldn't work. > > My code is below. But can someone please explain to me why the following variable has to be placed where it is for the code to work? I thought it would need to go nearer the start of the code i.e. just before heads = 0, tails = 0 etc: > >? ? ? ? ? ? ? ? ? coin = random.randrange(2) Python runs through your code, step by step. I believe it starts at the top and goes down, following the logic of your code. When you make Python refer to a variable in your while loop that Python has not encountered yet, then it will not know what to do -- and complain about it. Solution: let Python know of the variable _before_ you then start to work with it. > > Also, why does the randrange integer have to be '2'? I only discovered this worked by complete accident. I tried '1' and '0,1' as my integers but they just didn't work. That is because your coin has _two_ sides, and you therefore want a random choice out of _two_ possibilities. With the random.randrange(2) function the choices will be 0 and 1, satisfying your demands. This means that the randrange() function goes up to, but not including, the integer you supply. It amounts to two choices in the end all the same because the counting starts with 0 instead of 1. That is, if you chose randrange(1) you will get only one answer, namely 0. If you type randrange(0) then you will get an error message (ValueError: empty range for randrange). Which makes sense. Remember, randrange() goes up to, but not including the integer supplied. HTH, David > > Thanks, > > Lawrence > > > import random > print "The Coin Flip Game\n" > > heads = 0 > tails = 0 > count = 0 > > while count? ? ? coin = random.randrange(2) >? ? ? if coin == 0: >? ? ? ? ? heads = heads + 1 >? ? ? else: >? ? ? ? ? tails = tails + 1 >? ? ? count += 1 > > print "Heads: ", heads > print "Tails: ", tails > > raw_input("\nPress enter to exit.") > > > > > > > > _______________________________________________ > Tutor maillist? -? Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor _______________________________________________ Tutor maillist? -? Tutor at python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor -------------- next part -------------- An HTML attachment was scrubbed... URL: From quasipedia at gmail.com Fri Feb 12 16:33:04 2010 From: quasipedia at gmail.com (Mac Ryan) Date: Fri, 12 Feb 2010 16:33:04 +0100 Subject: [Tutor] Tutor list as pair progamming plush toy Message-ID: <1265988784.21902.10.camel@jabbar> Have you ever got that piece of advice about - when you have stuck on a bug you seem unable to track - getting a plush toy to whom you explain your code? (This is of course a workaround if you do not have a fellow developer to help you out). Well... I found out this advice kind of works for me, with the notable difference that my plush toy is this mailing list. It works so wonderfully that indeed is several months I do not post any message: whenever I get stuck, I begin to write a message to the list, and in the process of explaining what is the intended behaviour and outcome of my code, I systematically find the bug by myself. I know - this is slightly OT for the list - but I thought to share as maybe this is a "hidden benefit" the list is bringing to a few people without the tutors even knowing it. Does anybody else experience the same? Cheers, :) Mac. From zstumgoren at gmail.com Fri Feb 12 17:05:30 2010 From: zstumgoren at gmail.com (Serdar Tumgoren) Date: Fri, 12 Feb 2010 11:05:30 -0500 Subject: [Tutor] Tutor list as pair progamming plush toy In-Reply-To: <1265988784.21902.10.camel@jabbar> References: <1265988784.21902.10.camel@jabbar> Message-ID: In similar vein, I find that a concept suddenly makes more sense to me when I try to explain it to someone else (or I realize that I don't fully understand and need to do some more research). But with regard to the plush toy you mention, I just ran into that anecdote in Coders at Work. Can't recall off the top of my head which developer mentioned it, but it's an interesting concept. Btw, I'd recommend that book to anyone interested in expanding their horizons on coding philosophies and methodologies. Some of it's pretty high-brow comp sci discussion, but there's a lot about basic testing and debugging approaches, and how one should go about reading someone else's code. I'm only half-way through the book, but the variety of responses and approaches is fascinating. Serdar -------------- next part -------------- An HTML attachment was scrubbed... URL: From Mike.Hansen at atmel.com Fri Feb 12 17:55:59 2010 From: Mike.Hansen at atmel.com (Hansen, Mike) Date: Fri, 12 Feb 2010 09:55:59 -0700 Subject: [Tutor] Tutor list as pair progamming plush toy In-Reply-To: <1265988784.21902.10.camel@jabbar> References: <1265988784.21902.10.camel@jabbar> Message-ID: <7941B2693F32294AAF16C26B679A258D0ECC3CF5@csomb01.corp.atmel.com> > -----Original Message----- > From: tutor-bounces+mike.hansen=atmel.com at python.org > [mailto:tutor-bounces+mike.hansen=atmel.com at python.org] On > Behalf Of Mac Ryan > Sent: Friday, February 12, 2010 8:33 AM > To: tutor at python.org > Subject: [Tutor] Tutor list as pair progamming plush toy > > Have you ever got that piece of advice about - when you have > stuck on a > bug you seem unable to track - getting a plush toy to whom you explain > your code? (This is of course a workaround if you do not have a fellow > developer to help you out). > > Well... I found out this advice kind of works for me, with the notable > difference that my plush toy is this mailing list. It works so > wonderfully that indeed is several months I do not post any message: > whenever I get stuck, I begin to write a message to the list, > and in the > process of explaining what is the intended behaviour and outcome of my > code, I systematically find the bug by myself. > > I know - this is slightly OT for the list - but I thought to share as > maybe this is a "hidden benefit" the list is bringing to a few people > without the tutors even knowing it. > > Does anybody else experience the same? > > Cheers, :) > Mac. > This kind of sounds like the rubber duck method of debugging. http://lists.ethernal.org/oldarchives/cantlug-0211/msg00174.html Mike From waynejwerner at gmail.com Fri Feb 12 17:58:15 2010 From: waynejwerner at gmail.com (Wayne Werner) Date: Fri, 12 Feb 2010 10:58:15 -0600 Subject: [Tutor] Tutor list as pair progamming plush toy In-Reply-To: References: <1265988784.21902.10.camel@jabbar> Message-ID: <333efb451002120858u1d5c6603j2edc4249ae01026a@mail.gmail.com> I've discovered that same thing. Usually I end out not sending my message because in the process of composing my email I end out I, too, find the errors. -Wayne -------------- next part -------------- An HTML attachment was scrubbed... URL: From kp8 at mac.com Fri Feb 12 17:22:42 2010 From: kp8 at mac.com (kevin parks) Date: Sat, 13 Feb 2010 01:22:42 +0900 Subject: [Tutor] batch file processing w/ python using cmd line executable? Message-ID: hi I am new territory here and not even sure where to start poking around other than the os module some. Essentially i need to do something like a shell script for batch processing gobs of files. I am trying to use a command line tool (sox, an open source sound file converter that runs from the unix command line) and I don't want to edit the command line, run the job, edit the command line, etc over and over again for hundreds of small files. I wonder if it is possible to use python to call sox and have it do os.mkdir, process all the input files in a particular directory and put the converted files into the directory it made with mkdir... so if i had kp/flute/ST kp8/flute/ST/foo01.aif kp8/flute/ST/foo02.aif kp8/flute/ST/foo03.aif kp8/flute/ST/foo04.aif kp8/flute/ST/foo05.aif The script would call sox repeatedly and create a new dir with a converted file for each found in the original folder. like so: kp/flute/STout/ kp/flute/STout/foo01.wav kp/flute/STout/foo02.wav kp/flute/STout/foo03.wav kp/flute/STout/foo04.wav kp/flute/STout/foo05.wav what makes this especially hairy is that sox is a monster an typically needs a crazy number of arguments, though these would be the same for the whole batch. A typical command line call i need to make to, say, batch convert files from one sample rate and bit depth to another would look like so: % sox -V3 -D -S St.01.aif -b16 kp/flute/STout/St.01.wav rate -s -v 44100 Is there away to do this in python, by just pointing it to a whole dir of files and say "do it" to all of these? cheers, kevin From grflanagan at gmail.com Fri Feb 12 19:35:10 2010 From: grflanagan at gmail.com (Gerard Flanagan) Date: Fri, 12 Feb 2010 18:35:10 +0000 Subject: [Tutor] Algorithm for combination analysis suggestion. In-Reply-To: References: Message-ID: Matthew Matson wrote: > > Hi Tutors, > > I am looking for the proper approach regarding the analysis of a > dictionary of combinations I have. > > What I need to do is read from a supplied text file that has a unique ID > and that unique ID's associated combination of elements. So let's say I > have the following lines in a text file (real file could be millions of > lines): > > "ID" "Elements" > 1 'A, B, C, D' > 2 'A, D' > 3 'D, E' > 4 'A, D' > 5 'A, B' > 6 'A, C, D' > > and I do something like... > > combinationDict = {} > for line in file: > data = line.split('\t') > comb = tuple(data[1].split(',')) > if comb not in combinationDict: > combinationDict[comb] = 1 > else: > combination[comb] +=1 > > Now after I read all of the data I end up with a dictionary with the > combination as the key and the associated total qty as its value. > > print combinationDict > {('A','B','C','D'):1, ('A','D'):2, ('D','E'):1, ('A','B'):1, ('A', 'C', > 'D'):1} > > What I am looking for is a starting point for a solution in python to > analyze the combination list so that I can determine for example that > ('A', 'D') is the most popular combination and then determining how many > other combinations in the dictionary contain this combination. > > I would like to incorporate some parameters so for example the > combination ('A','B','C','D') and ('A', 'C', 'D') contain ('A','D') so > they are valid but I could also say that as long as one element is > contained in a combination it is valid as well provided I add no more > than one additional item to the combination. If I apply this logic then > ('D','E') can ('A','B') can contain ('A', 'D') and if I apply this to > the combination dictionary I have: > > {('B','C', ('A', 'D')):1, ('A','D'):2, ('E', ('A', 'D')):1, ('B', ('A', > 'D')):1, ('C', ('A', 'D')):1} > > which I could then query the keys for ('A', 'D') inclusion to get a > total of 4 for ('A', 'D'). > > I hope this isn't too long and confusing but I am looking for an > approach where I can analyze for the highest quantity of combinations > and then iterate through the dictionary substituting those combinations > that were determined a "highest qty" combination into other low qty > combinations when valid. > > I was hoping to have parameters to qualify a high qty combination (e.g. > every combination with qty above 10,000) with the highest quantity of > that determined set taking precedence for substitution for the first > pass then moving on to the next highest combination for the second pass > of substitution etc.. The other parameter would be for the combination > that would receive a substitution whereby I might say that I can only > substitute if a substitution results in only one additional > (superfluous) value being added to the combination existing low qty > combination. > > I have looked around and this sounds like it might be similar to a > packing problem and in particular the knapsack problem but I can't seem > to wrap my head around an approach for this in python. I am not looking > for a solution just some guidance on a starting point or perhaps > libraries that may be helpful. > > Thank you. > > Hey, never heard of commas! I'm out of breath after that ;-) It sounds something like Linear Programming - not that I know much about it, but maybe asking on other lists, eg. scipy, might turn up some kind of standard approach to this kind of problem. One idea for the 'is a combination contained in another combination' issue is using bitmasks. Create a bitmask for each combination, then C1 is a component of C2 if C1 & C2 == C1. (Hope i've got that right!) Some code doodling below shows the idea. Regards G.F. ----------------------------------------------------- from collections import defaultdict data = """ 1 A, B, C, D 2 A, D 3 D, E 4 A, D 5 A, B 6 A, C, D 7 E """.splitlines() atoms = {} key2mask = {} mask2key = {} combos = defaultdict(int) for line in data: if line: key = '' mask = 0 for atom in line[5:].split(','): atom = atom.strip() key += atom mask |= atoms.setdefault(atom, 1 << len(atoms)) key2mask[key] = mask mask2key[mask] = key combos[mask] += 1 for combo in ['AB', 'AD', 'DE', 'E']: mask = key2mask[combo] print for c in combos.iterkeys(): if mask & c == mask: print '%s is a component of %s' % (combo, mask2key[c]) print 'there are %s %ss' % (combos[mask], combo) ------------------------------------------------------ def xuniqueCombinations(items, n): if n==0: yield [] else: for i in xrange(len(items)): for cc in xuniqueCombinations(items[i+1:],n-1): yield [items[i]]+cc def allcombos(): for k in range(1,6): for c in xuniqueCombinations('ABCDE', k): yield c ------------------------------------------------------- From dwightdhutto at yahoo.com Fri Feb 12 19:40:20 2010 From: dwightdhutto at yahoo.com (David Hutto) Date: Fri, 12 Feb 2010 10:40:20 -0800 (PST) Subject: [Tutor] Tutor list as pair progamming plush toy In-Reply-To: <7941B2693F32294AAF16C26B679A258D0ECC3CF5@csomb01.corp.atmel.com> Message-ID: <253553.41844.qm@web45303.mail.sp1.yahoo.com> --- On Fri, 2/12/10, Hansen, Mike wrote: From: Hansen, Mike Subject: Re: [Tutor] Tutor list as pair progamming plush toy To: tutor at python.org Date: Friday, February 12, 2010, 11:55 AM > -----Original Message----- > From: tutor-bounces+mike.hansen=atmel.com at python.org > [mailto:tutor-bounces+mike.hansen=atmel.com at python.org] On > Behalf Of Mac Ryan > Sent: Friday, February 12, 2010 8:33 AM > To: tutor at python.org > Subject: [Tutor] Tutor list as pair progamming plush toy > > Have you ever got that piece of advice about - when you have > stuck on a > bug you seem unable to track - getting a plush toy to whom you explain > your code? (This is of course a workaround if you do not have a fellow > developer to help you out). > > Well... I found out this advice kind of works for me, with the notable > difference that my plush toy is this mailing list. It works so > wonderfully that indeed is several months I do not post any message: > whenever I get stuck, I begin to write a message to the list, > and in the > process of explaining what is the intended behaviour and outcome of my > code, I systematically find the bug by myself. > > I know - this is slightly OT for the list - but I thought to share as > maybe this is a "hidden benefit" the list is bringing to a few people > without the tutors even knowing it. > > Does anybody else experience the same? > > Cheers, :) > Mac. > +1 -------------- next part -------------- An HTML attachment was scrubbed... URL: From alan.gauld at btinternet.com Fri Feb 12 20:54:27 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Fri, 12 Feb 2010 19:54:27 -0000 Subject: [Tutor] Tutor list as pair progamming plush toy References: <1265988784.21902.10.camel@jabbar> Message-ID: "Mac Ryan" wrote > I know - this is slightly OT for the list - but I thought to share as > maybe this is a "hidden benefit" the list is bringing to a few people > without the tutors even knowing it. Actually I think it is bang on topic. One of the most common benefits of any online community is the way we are foced to think about propblems to write them down. Doing so ioften brings new solutions to mind. In fact I often find solutioons to my own problems while replying to others! - even on seemingly unrelated issues :-) And of course if the solution doesn't come you have the 2nd level support option of actually posting and getting replies! :-) -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From alan.gauld at btinternet.com Fri Feb 12 21:00:42 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Fri, 12 Feb 2010 20:00:42 -0000 Subject: [Tutor] batch file processing w/ python using cmd line executable? References: Message-ID: "kevin parks" wrote > I wonder if it is possible to use python to call sox and have it do > os.mkdir, process all the input files in a particular directory and > put the converted files into the directory it made with mkdir... Of course. What do you perceive to be the problem? This would just be a standard loop or os.walk call. > The script would call sox repeatedly and create a new dir with a > converted file for each found in the original folder. like so: Presumably a new dir for each dir found? Thus mirroring the source structure? Thats easily done with os.walk and would be a good place to start writing the script. Calling sox can be done using the subprocess module. > what makes this especially hairy is that sox is a monster an typically > needs a crazy number of arguments, though these would be the same for > the whole batch. So store them in a list and apply them to each call. subprocess makes this easy. > % sox -V3 -D -S St.01.aif -b16 kp/flute/STout/St.01.wav rate -s -v > 44100 > > Is there away to do this in python, by just pointing it to a whole dir > of files and say "do it" to all of these? I'd check out os.walk and subprocess. Both are discussed in the Using the OS topic in my tutorial. -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From marky1991 at gmail.com Sat Feb 13 00:41:09 2010 From: marky1991 at gmail.com (Mark Young) Date: Fri, 12 Feb 2010 18:41:09 -0500 Subject: [Tutor] Defining operators for custom types Message-ID: I created a custom vector type, inheriting from object, and defined __mul__, __add__, etc. Unfortunately, the operators only work if I type "vector * (int/float/number)", in that exact order. My program produces an error if I instead type "number * vector". This makes sense to me, because I haven't told the number (int, float, whatever) how to deal with an object of type vector, (At least, I think that's why it doesn't work.). Is there any way to allow "number (operator) vector", short of modifying the standard types' behavior? Here's an example of the error. vec1 = vector(5,6,7) >>> vec1 * 2 (10, 12, 14) >>> 2 * vec1 Traceback (most recent call last): File "", line 1, in 2 * vec1 TypeError: unsupported operand type(s) for *: 'int' and 'vector' I'm using python 3.1. Thanks. -------------- next part -------------- An HTML attachment was scrubbed... URL: From bgailer at gmail.com Sat Feb 13 01:11:13 2010 From: bgailer at gmail.com (bob gailer) Date: Fri, 12 Feb 2010 19:11:13 -0500 Subject: [Tutor] Defining operators for custom types In-Reply-To: References: Message-ID: <4B75EE21.8010208@gmail.com> Mark Young wrote: > I created a custom vector type, inheriting from object, and defined > __mul__, __add__, etc. Unfortunately, the operators only work if I > type "vector * (int/float/number)", in that exact order. My program > produces an error if I instead type "number * vector". Use __rmul__, __radd__, etc. > This makes sense to me, because I haven't told the number (int, float, > whatever) how to deal with an object of type vector, (At least, I > think that's why it doesn't work.). Is there any way to allow > "number (operator) vector", short of modifying the standard types' > behavior? > > Here's an example of the error. > vec1 = vector(5,6,7) > >>> vec1 * 2 > (10, 12, 14) > >>> 2 * vec1 > Traceback (most recent call last): > File "", line 1, in > 2 * vec1 > TypeError: unsupported operand type(s) for *: 'int' and 'vector' > > I'm using python 3.1. > Thanks. > ------------------------------------------------------------------------ > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > -- Bob Gailer 919-636-4239 Chapel Hill NC From marky1991 at gmail.com Sat Feb 13 01:19:36 2010 From: marky1991 at gmail.com (Mark Young) Date: Fri, 12 Feb 2010 19:19:36 -0500 Subject: [Tutor] Defining operators for custom types In-Reply-To: <4B75EE21.8010208@gmail.com> References: <4B75EE21.8010208@gmail.com> Message-ID: Thanks for the help. That's exactly the kind of solution I wanted. I've been to that page several times already, but just ignored that section apparently. Thanks alot. -------------- next part -------------- An HTML attachment was scrubbed... URL: From garry.willgoose at newcastle.edu.au Sat Feb 13 00:51:38 2010 From: garry.willgoose at newcastle.edu.au (Garry Willgoose) Date: Sat, 13 Feb 2010 10:51:38 +1100 Subject: [Tutor] aliasing an imported module Message-ID: <0A04999D-5173-4355-A1E6-1BAD757DC2BD@newcastle.edu.au> I want to be able to import multiple instances of a module and call each by a unique name and it doesn't appear at first glance that either import or __import__ have what I need. I need this because of computing platform I have developed where users write python scripts to do some analysis of science problems where they call modules that have code for monipulating data and where the imported module does some specific scientfic manipulation of data. The key problem is that the module might locally store some partial results ready for the next time its called to save CPU time (typically the results for one timestep ready for the next timestep). But if the module is called for two different purposes in two different parts of the script then the second call will actually see the partial results from the 1st call and vice versa. The simple solution is if it were possible to import the same module file twice but for them to act like they were different modules. It was also make it easy to parallelise code without the called module needing to be thread safe (each instance would be one thread) but that is a lesser priority for the moment. If I have module in a file called stuff.py has in it a global variable somevariable I want to be able to import multiple instance (with seperate name spaces etc) of stuff so that I could have for example a=instance1ofstuff.somevariable b=instance2ofstuff.somevariable and a and b are referring to different variables in entirely different modules. IS there any way to do this? ==================================================================== Prof Garry Willgoose, Australian Professorial Fellow in Environmental Engineering, Director, Centre for Climate Impact Management (C2IM), School of Engineering, The University of Newcastle, Callaghan, 2308 Australia. Centre webpage: www.c2im.org.au Phone: (International) +61 2 4921 6050 (Tues-Fri AM); +61 2 6545 9574 (Fri PM-Mon) FAX: (International) +61 2 4921 6991 (Uni); +61 2 6545 9574 (personal and Telluric) Env. Engg. Secretary: (International) +61 2 4921 6042 email: garry.willgoose at newcastle.edu.au; g.willgoose at telluricresearch.com email-for-life: garry.willgoose at alum.mit.edu personal webpage: www.telluricresearch.com/garry ==================================================================== "Do not go where the path may lead, go instead where there is no path and leave a trail" Ralph Waldo Emerson ==================================================================== From alan.gauld at btinternet.com Sat Feb 13 02:57:30 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Sat, 13 Feb 2010 01:57:30 -0000 Subject: [Tutor] aliasing an imported module References: <0A04999D-5173-4355-A1E6-1BAD757DC2BD@newcastle.edu.au> Message-ID: "Garry Willgoose" wrote >I want to be able to import multiple instances of a module and call each >by a unique name and it doesn't appear at first glance that either import >or __import__ have what I need. No because it would be bad practice. Stateful modules lead to hard to debug prolems. > computing platform I have developed where users write python scripts to > do some analysis of science problems where they call modules that have > code for monipulating data and where the imported module does some > specific scientfic manipulation of data. The key problem is that the > module might locally store some partial results ready for the next time > its called to save CPU time This is where classes come in. You can define a class in your module with the analysis done in a method and have it store the results in instance variables. Then you can either call another method which can access those variables or you can create another instance of the class with its own independant copies of its values. > But if the module is called for two different purposes in two different > parts of the script then the second call will actually see the partial > results from the 1st call and vice versa. Technically you don't call a module you import it which has the side-effect of executing the code in the module. In a well structured module the code should really be inside function definitions so that nothing haoppens until you call the modules functions. importing modules as a way of executing the code within them is not good practice. > The simple solution is if it were possible to import the same module > file twice but for them to act like they were different modules. It was > also make it easy to parallelise code without the called module needing > to be thread safe (each instance would be one thread) but that is a > lesser priority for the moment. Again classes can do that for you. Either by having two instances of the class in a single thread and multiplexing the calls to their methods (round-robin style) or, if necessary, by having two instances each in their own thread executing independantly. > If I have module in a file called stuff.py has in it a global variable > somevariable I want to be able to import multiple instance (with > seperate name spaces etc) of stuff so that I could have for example > > a=instance1ofstuff.somevariable > b=instance2ofstuff.somevariable With a class that becomes: import stuff a = stuff.myClass() b = stuff.myClass() a.myFunction(x,y,z) b.myFunction(a,b,c) print a.myvar, b.myvar etc. > and a and b are referring to different variables in entirely different > modules. IS there any way to do this? a and b refer to independant instances of the same class each with its own myvar variable inside. See the OOP topic of my tutorial for more on Object Oriented Programming HTH, -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From randyeraymond at mchsi.com Sat Feb 13 03:30:15 2010 From: randyeraymond at mchsi.com (Randy Raymond) Date: Fri, 12 Feb 2010 20:30:15 -0600 Subject: [Tutor] Just a Note Message-ID: <5323715525EA4925A05B0EF6E0A94AF3@RandyPC> By the way, Alan Gauld's emails generate an error in my system. His is the only emails I have a problem with so far. At first it tried to open a News service. Randy Raymond -------------- next part -------------- An HTML attachment was scrubbed... URL: From rabidpoobear at gmail.com Sat Feb 13 03:40:12 2010 From: rabidpoobear at gmail.com (Luke Paireepinart) Date: Fri, 12 Feb 2010 20:40:12 -0600 Subject: [Tutor] Just a Note In-Reply-To: <5323715525EA4925A05B0EF6E0A94AF3@RandyPC> References: <5323715525EA4925A05B0EF6E0A94AF3@RandyPC> Message-ID: This doesn't make any sense. What do you mean "tries to open up a news service"? When you read the e-mail? What system are you using? On Fri, Feb 12, 2010 at 8:30 PM, Randy Raymond wrote: > By the way, Alan Gauld's emails generate an error in my system. His is > the only emails I have a problem with so far. At first it tried to open a > News service. > > Randy Raymond > > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From sierra_mtnview at sbcglobal.net Sat Feb 13 04:55:43 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Fri, 12 Feb 2010 19:55:43 -0800 Subject: [Tutor] The Order of Imports and install order of modules and other matters (XP vs W7, ...) Message-ID: <4B7622BF.9000408@sbcglobal.net> There seems to be something of a general consensus in ordering import statements. Something like standard library imports first. When using tools like matlablib or tkinter (maybe), must one keep an order among the relevant imports? Related to this is the order in which modules are installed. Does it make a difference? Finally, I'm in the process of moving Python code from XP to Win7. I just grabbed all the install files I have from XP, and executed them on W7. Everything seems to be working as expected, but one strange thing happened with scipy. It produced a warning about something like "unable to provide key". I continued anyway. All seems well. Was I supposed to use some W7 version of the "XP" files? This is anomaly 1. OK, this the last one. In both XP and W7, I've found executing a program by use of the py file (not IDLE. Is there a name for this method?) using numpy that see early on in the DOS-like window (is there name for it too?) it's complaining (alerting me) about deprecations and some use of a numpy test. What's that about? This is anomaly 2. -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From eduardo.susan at gmail.com Sat Feb 13 05:49:15 2010 From: eduardo.susan at gmail.com (Eduardo Vieira) Date: Fri, 12 Feb 2010 21:49:15 -0700 Subject: [Tutor] Not understanding this code example. Help, please. Message-ID: <9356b9f31002122049w5cde73cbqb8c1f231367bd15a@mail.gmail.com> Hello! I was reading the latest version of Mark Pilgrim's "Dive into Python" and am confused with these example about the pluralization rules. See http://diveintopython3.org/examples/plural3.py and http://diveintopython3.org/generators.html#a-list-of-patterns Here is part of the code: import re def build_match_and_apply_functions(pattern, search, replace): def matches_rule(word): return re.search(pattern, word) def apply_rule(word): return re.sub(search, replace, word) return (matches_rule, apply_rule) patterns = \ ( ('[sxz]$', '$', 'es'), ('[^aeioudgkprt]h$', '$', 'es'), ('(qu|[^aeiou])y$', 'y$', 'ies'), ('$', '$', 's') ) rules = [build_match_and_apply_functions(pattern, search, replace) for (pattern, search, replace) in patterns] def plural(noun): for matches_rule, apply_rule in rules: if matches_rule(noun): return apply_rule(noun) this example works on IDLE: print plural("baby") My question is "baby" assigned to "word" in the inner function? It's a little mind bending for me... Thanks, Eduardo From alan.gauld at btinternet.com Sat Feb 13 10:18:57 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Sat, 13 Feb 2010 09:18:57 -0000 Subject: [Tutor] Just a Note References: <5323715525EA4925A05B0EF6E0A94AF3@RandyPC> Message-ID: "Randy Raymond" wrote > By the way, Alan Gauld's emails generate an error in my system. > His is the only emails I have a problem with so far. > At first it tried to open a News service. Interesting. I am using the gmane news server but I've not heard of anyone else having problems. Is there anyone else? Alan G. From alan.gauld at btinternet.com Sat Feb 13 10:27:42 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Sat, 13 Feb 2010 09:27:42 -0000 Subject: [Tutor] Not understanding this code example. Help, please. References: <9356b9f31002122049w5cde73cbqb8c1f231367bd15a@mail.gmail.com> Message-ID: "Eduardo Vieira" wrote > def build_match_and_apply_functions(pattern, search, replace): > def matches_rule(word): > return re.search(pattern, word) > def apply_rule(word): > return re.sub(search, replace, word) > return (matches_rule, apply_rule) > > patterns = \ > ( > ('[sxz]$', '$', 'es'), > ('[^aeioudgkprt]h$', '$', 'es'), > ('(qu|[^aeiou])y$', 'y$', 'ies'), > ('$', '$', 's') > ) > rules = [build_match_and_apply_functions(pattern, search, replace) > for (pattern, search, replace) in patterns] > > def plural(noun): > for matches_rule, apply_rule in rules: > if matches_rule(noun): > return apply_rule(noun) > > My question is "baby" assigned to "word" in the inner function? It's a > little mind bending for me... Yes. rules is a list comprehension that builds a list of 3 pairs of functions. These functions are returned from the first function above. Those functions both take a word as an argument. in plural it iterates over these pairs of functions and applies noun as the argument to both functtions, so noun gets applied as the word parameter to both functions. And yes it is a little mind bending and there are more straighforward ways to code it, but they require more code and don't show off the use of higher order functions. It depends on what the book is actually trying to explain here whether this approach is sensible or not. HTH, -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From alan.gauld at btinternet.com Sat Feb 13 10:33:01 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Sat, 13 Feb 2010 09:33:01 -0000 Subject: [Tutor] The Order of Imports and install order of modules and other matters (XP vs W7, ...) References: <4B7622BF.9000408@sbcglobal.net> Message-ID: "Wayne Watson" wrote > There seems to be something of a general consensus in ordering import > statements. Something like standard library imports first. I've never seen anything written down but its true I tend to do that. But its not been a conscious thing... > tools like matlablib or tkinter (maybe), must one keep an order among > the relevant imports? The order can be significant, especially if the module code has executable statements in it or there are dependencies between them. But with well written modules it should not matter provided you use the straightforward import m style. It will matter if you use the from m import * method though, because of likely name collisions. > Related to this is the order in which modules are installed. Does it > make a difference? Again it shouldn't but if the installer for one relies on another (eg a GUI library) then it will. > Finally, I'm in the process of moving Python code from XP to Win7. I Sorry, I know nothing of W7... :-) Alan G From pythonnewbie6 at gmail.com Sat Feb 13 13:21:43 2010 From: pythonnewbie6 at gmail.com (Chris Patillo) Date: Sat, 13 Feb 2010 06:21:43 -0600 Subject: [Tutor] json file Message-ID: <5f3def2d1002130421q4115c300ic2e38f9726a2c1f@mail.gmail.com> I need to read in a .json file and write out a file with some of the information from this file. I can't figure out how to read the .json file in. I know there is a module for this, but I don't understand how it works. The file I am needing to read is like below (except much much larger) { "table":"contacts", "records":[ { "name":"John", "phone":"555-555-4444" }, { "name":"Jane", "phone":"555-555-3333" }, ] } I have no clue how to do this. I was thinking something like; import json json.dumps([name,phone], seperators(":")) Would something like this even remotely stand a chance of working? If not can someone explain the json module to me in a way that is easy to understand? All my past experience has been in reading ism files in a different language - I've never read a java file before and haven't done much python coding either. If this statement would work, then how do I get it to give me the data for one record at a time so I can then move it to another file? I would really appreciate any help I could get with this. -------------- next part -------------- An HTML attachment was scrubbed... URL: From kent37 at tds.net Sat Feb 13 15:59:00 2010 From: kent37 at tds.net (Kent Johnson) Date: Sat, 13 Feb 2010 09:59:00 -0500 Subject: [Tutor] Not understanding this code example. Help, please. In-Reply-To: <9356b9f31002122049w5cde73cbqb8c1f231367bd15a@mail.gmail.com> References: <9356b9f31002122049w5cde73cbqb8c1f231367bd15a@mail.gmail.com> Message-ID: <1c2a2c591002130659h4e3f40cfh5cc304f5c53397e4@mail.gmail.com> On Fri, Feb 12, 2010 at 11:49 PM, Eduardo Vieira wrote: > Hello! I was reading the latest version of Mark Pilgrim's "Dive into > Python" and am confused with these example about the pluralization > rules. See http://diveintopython3.org/examples/plural3.py and > http://diveintopython3.org/generators.html#a-list-of-patterns > Here is part of the code: > import re > > def build_match_and_apply_functions(pattern, search, replace): > ? ?def matches_rule(word): > ? ? ? ?return re.search(pattern, word) > ? ?def apply_rule(word): > ? ? ? ?return re.sub(search, replace, word) > ? ?return (matches_rule, apply_rule) > > patterns = \ > ?( > ? ?('[sxz]$', ? ? ? ? ? '$', ?'es'), > ? ?('[^aeioudgkprt]h$', '$', ?'es'), > ? ?('(qu|[^aeiou])y$', ?'y$', 'ies'), > ? ?('$', ? ? ? ? ? ? ? ?'$', ?'s') > ?) > rules = [build_match_and_apply_functions(pattern, search, replace) > ? ? ? ? for (pattern, search, replace) in patterns] > > def plural(noun): > ? ?for matches_rule, apply_rule in rules: > ? ? ? ?if matches_rule(noun): > ? ? ? ? ? ?return apply_rule(noun) > > this example works on IDLE: print plural("baby") > My question is "baby" assigned to "word" in the inner function? It's a > little mind bending for me... It is a little mind bending when you first start seeing functions used as first-class objects. In Python functions are values that can be passed as arguments, returned, and assigned just like any other value. This can simplify a lot of problems. In this case I think the use of functions makes the code needlessly complicated. Without build_match_and_apply_functions() and the rules list it would look like this: def plural(noun): for (pattern, search, replace) in patterns: if re.search(pattern, noun): return re.replace(search, replace, noun) which is not much longer that the original plural(), doesn't require all the helper machinery and IMO is easier to understand. Kent From kent37 at tds.net Sat Feb 13 16:06:02 2010 From: kent37 at tds.net (Kent Johnson) Date: Sat, 13 Feb 2010 10:06:02 -0500 Subject: [Tutor] The Order of Imports and install order of modules and other matters (XP vs W7, ...) In-Reply-To: <4B7622BF.9000408@sbcglobal.net> References: <4B7622BF.9000408@sbcglobal.net> Message-ID: <1c2a2c591002130706i6aa1b99boc019f7f37d2c8804@mail.gmail.com> On Fri, Feb 12, 2010 at 10:55 PM, Wayne Watson wrote: > There seems to be something of a general consensus in ordering import > statements. Something like standard library imports first. When using tools > like matlablib or tkinter (maybe), must one keep an order among the relevant > imports? I don't know if there is a general consensus but what I like to do is standard library imports third-party library imports application-specific imports Within each group I tend to group "import x" imports before "from x import y" imports and alphabetize by module name. I'm not strict about that though. > Related to this is the order in which modules are installed. Does it make a > difference? It shouldn't matter. > Finally, I'm in the process of moving Python code from XP to Win7. I just > grabbed all the install files I have from XP, and executed them on W7. > Everything seems to be working as expected, but one strange thing happened > with scipy. It produced a warning about something like "unable to provide > key". ?I continued anyway. All seems well. Was I supposed to use some W7 > version of the "XP" files? This is anomaly 1. There doesn't seem to be a separate installer for W7 but there may be issues, W7 is still pretty new. Also check that you are using the most recent scipy. > OK, this the last one. In both XP and W7, I've found executing a program by > use of the py file (not IDLE. Is there a name for this method?) using numpy > that ?see early on in the DOS-like window (is there name for it too?) it's > complaining (alerting me) about deprecations and some use of a numpy test. > What's that about? This is anomaly 2. Deprecation warnings mean the code is using some outdated functionality that is slated to be removed. You should at least look at them and see if it is in your code or in scipy. Kent > -- > "Crime is way down. War is declining. And that's far from the good news." -- > Steven Pinker (and other sources) Why is this true, but yet the media says > otherwise? The media knows very well how to manipulate us (see limbic, > emotion, $$). -- WTW > _______________________________________________ > Tutor maillist ?- ?Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > From kent37 at tds.net Sat Feb 13 16:11:18 2010 From: kent37 at tds.net (Kent Johnson) Date: Sat, 13 Feb 2010 10:11:18 -0500 Subject: [Tutor] json file In-Reply-To: <5f3def2d1002130421q4115c300ic2e38f9726a2c1f@mail.gmail.com> References: <5f3def2d1002130421q4115c300ic2e38f9726a2c1f@mail.gmail.com> Message-ID: <1c2a2c591002130711t247e2538vce591036a0bf733a@mail.gmail.com> On Sat, Feb 13, 2010 at 7:21 AM, Chris Patillo wrote: > I need to read in a .json file and write out a file with some of the > information from this file.? I can't figure out how to read the .json file > in.? I know there is a module for this, but I don't understand how it works. > > The file I am needing to read is like below (except much much larger) > > { > > ?? "table":"contacts", > > ?? "records":[ > > ?? ? ?{ > > ?? ? ? ? "name":"John", > > ?? ? ? ? "phone":"555-555-4444" > > ?? ? ?}, > > ?? ? ?{ > > ?? ? ? ? "name":"Jane", > > ?? ? ? ? "phone":"555-555-3333" > > ?? ? ?}, > > ?? ] > > } > > > > I have no clue how to do this.? I was thinking something like; > > import json > > json.dumps([name,phone], seperators(":")) json.dumps() converts a structure to a json string. json.load() is what you want. If your file is called data.json, try import json data = json.load(open('data.json')) print data If your data is not Ascii or UTF-8 you have to specify the encoding to json.load(). Kent From waynejwerner at gmail.com Sat Feb 13 16:37:07 2010 From: waynejwerner at gmail.com (Wayne Werner) Date: Sat, 13 Feb 2010 09:37:07 -0600 Subject: [Tutor] Just a Note In-Reply-To: References: <5323715525EA4925A05B0EF6E0A94AF3@RandyPC> Message-ID: <333efb451002130737md7b2bf6u6d07b91de33a6888@mail.gmail.com> On Sat, Feb 13, 2010 at 3:18 AM, Alan Gauld wrote: > > "Randy Raymond" wrote > > By the way, Alan Gauld's emails generate an error in my system. His is >> the only emails I have a problem with so far. At first it tried to open a >> News service. >> > > Interesting. I am using the gmane news server but I've not heard of anyone > else having problems. Is there anyone else? Not I - gmail hasn't had any problems... at least that I know of. -Wayne -------------- next part -------------- An HTML attachment was scrubbed... URL: From sierra_mtnview at sbcglobal.net Sat Feb 13 17:14:31 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Sat, 13 Feb 2010 08:14:31 -0800 Subject: [Tutor] The Order of Imports and install order of modules and other matters (XP vs W7, ...) In-Reply-To: References: <4B7622BF.9000408@sbcglobal.net> Message-ID: <4B76CFE7.3090600@sbcglobal.net> Thanks, Alan. Some of what I've derived elsewhere almost sounds like hearsay or is anecdotal. I'm thinking here about forums and the like. However, I just grabbed my Core Python book, and noted than Chun mentions a preferred sequence. Std Lib, Third Party, App specific modules. He cites scoping rules. Another question on similar matters. If I write a program and "compile" it for distribution, and a user has 2.6 going to be able to execute it. I would like to the the compiled program is free of such restrictions. That is, it's an independent program. I would like to think that if I've been testing it successfully in IDLE, that the compiled version will produce everything I see in IDLE. For example, when I run it in IDLE, and make a connection to the (camera) h/w, a dos-like window appears that I otherwise never see. The program purposefully either sends warning and error messages there through some built-in facility or creates that window somehow. I'm dealing with tkinter in the app code. I didn't write the (1600 line) program, but certainly am modifying it. On 2/13/2010 1:33 AM, Alan Gauld wrote: > > "Wayne Watson" wrote > >> There seems to be something of a general consensus in ordering import >> statements. Something like standard library imports first. > > I've never seen anything written down but its true I tend to do that. > But its not been a conscious thing... ... -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From alan.gauld at btinternet.com Sat Feb 13 17:19:06 2010 From: alan.gauld at btinternet.com (ALAN GAULD) Date: Sat, 13 Feb 2010 16:19:06 +0000 (GMT) Subject: [Tutor] The Order of Imports and install order of modules and other matters (XP vs W7, ...) In-Reply-To: <4B76CFE7.3090600@sbcglobal.net> References: <4B7622BF.9000408@sbcglobal.net> <4B76CFE7.3090600@sbcglobal.net> Message-ID: <808178.25267.qm@web86704.mail.ird.yahoo.com> > Another question on similar matters. If I write a program and "compile" it for > distribution, and a user has 2.6 going to be able to execute it. I would like to > the the compiled program is free of such restrictions. That is, it's an > independent program. I would like to think that if I've been testing it > successfully in IDLE, that the compiled version will produce everything I see in > IDLE. Never ever, ever, test anything for distribution inside an IDE! Always test it as it will be run - from the OS prompt or filemanager. IDEs can introduce subtle differences of behaviour that conceal bugs. Similarly never ever do a final test with debuggng code switched on or the debugger active, again the debugger can cause subtle changes in behaviour. > For example, when I run it in IDLE, and make a connection to the (camera) > h/w, a dos-like window appears that I otherwise never see. The program > purposefully either sends warning and error messages there through some built-in > facility or creates that window somehow. I'm dealing with tkinter in the app > code. I didn't write the (1600 line) program, but certainly am modifying it. Do you run it with python or pythonw, that might also make a difference. HTH, Alan G. From sierra_mtnview at sbcglobal.net Sat Feb 13 17:20:02 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Sat, 13 Feb 2010 08:20:02 -0800 Subject: [Tutor] The Order of Imports and install order of modules and other matters (XP vs W7, ...) In-Reply-To: <1c2a2c591002130706i6aa1b99boc019f7f37d2c8804@mail.gmail.com> References: <4B7622BF.9000408@sbcglobal.net> <1c2a2c591002130706i6aa1b99boc019f7f37d2c8804@mail.gmail.com> Message-ID: <4B76D132.9010604@sbcglobal.net> Thanks, Kent. As of a day ago, I've moved my Python work to W7. For about the last 4 weeks, I've been using XP. Four weeks ago, I moved my mail and browser to W7, so trying to copy out from one PC to the other is a tale of juggling. Next time I have the deprecation and test msgs appear, I'll print them out, so that I can read the detail. I'm planning on making the code I'm writing available in a "compiled" form, exe. I hope those messages don't appear when users try to execute the program. On 2/13/2010 7:06 AM, Kent Johnson wrote: > On Fri, Feb 12, 2010 at 10:55 PM, Wayne Watson > wrote: > >> There seems to be something of a general consensus in ordering import >> statements. Something like standard library imports first. When using tools >> like matlablib or tkinter (maybe), must one keep an order among the relevant >> imports? >> > I don't know if there is a general consensus but what I like to do is > standard library imports > ... >> s that about? This is anomaly 2. >> > Deprecation warnings mean the code is using some outdated > functionality that is slated to be removed. You should at least look > at them and see if it is in your code or in scipy. > > Kent > > >> -- >> "Crime is way down. War is declining. And that's far from the good news." -- >> Steven Pinker (and other sources) Why is this true, but yet the media says >> otherwise? The media knows very well how to manipulate us (see limbic, >> emotion, $$). -- WTW >> _______________________________________________ >> Tutor maillist - Tutor at python.org >> To unsubscribe or change subscription options: >> http://mail.python.org/mailman/listinfo/tutor >> >> > -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From zepangolin at gmail.com Sat Feb 13 16:56:08 2010 From: zepangolin at gmail.com (patrice laporte) Date: Sat, 13 Feb 2010 16:56:08 +0100 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? Message-ID: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> Hi, Being in an exeption of my own, I want to print the name of the caller, and I'm looking for a way to have it. I've found a lot of recipe all of them using what seems to be, according to me, a not so good trick : all those recipe make use of sys._getframe(1).f_code.co_name, such as in this exemple : import sys def whoami(): print "Who call me ? : ", sys._getframe(1).f_code.co_name print "Who am I ? : ", sys._getframe(0).f_code.co_name def print_caller_name(): whoami() if __name__ == "__main__": print_caller_name() With the following result, as expected : Who call me ? : print_caller_name Who am I ? : whoami A closer look at the documentation about sys._getframe at http://docs.python.org/library/sys.html make me think it's not a good idea, because of the note : "*CPython implementation detail:* This function should be used for internal and specialized purposes only. *It is not guaranteed to exist in all implementations of Python*." So, this trick works today, but what about tomorow ? Is anybody have an idea how to get the the same result without _getframe ? Thanks Patrice. -------------- next part -------------- An HTML attachment was scrubbed... URL: From sierra_mtnview at sbcglobal.net Sat Feb 13 19:44:28 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Sat, 13 Feb 2010 10:44:28 -0800 Subject: [Tutor] The Order of Imports and install order of modules and other matters (XP vs W7, ...) In-Reply-To: <808178.25267.qm@web86704.mail.ird.yahoo.com> References: <4B7622BF.9000408@sbcglobal.net> <4B76CFE7.3090600@sbcglobal.net> <808178.25267.qm@web86704.mail.ird.yahoo.com> Message-ID: <4B76F30C.3060309@sbcglobal.net> Thanks. Sounds like good advice. BTW, I just did some advertising on the AstroPy NG a moment ago for your books. A query for good Py books. On 2/13/2010 8:19 AM, ALAN GAULD wrote: > > >> Another question on similar matters. If I write a program and "compile" it for >> distribution, and a user has 2.6 going to be able to execute it. I would like to >> the the compiled program is free of such restrictions. That is, it's an >> independent program. I would like to think that if I've been testing it >> successfully in IDLE, that the compiled version will produce everything I see in >> IDLE. >> > Never ever, ever, test anything for distribution inside an IDE! > Always test it as it will be run - from the OS prompt or filemanager. > > IDEs can introduce subtle differences of behaviour that conceal bugs. > > Similarly never ever do a final test with debuggng code switched > on or the debugger active, again the debugger can cause subtle > changes in behaviour. > > >> For example, when I run it in IDLE, and make a connection to the (camera) >> h/w, a dos-like window appears that I otherwise never see. The program >> purposefully either sends warning and error messages there through some built-in >> facility or creates that window somehow. I'm dealing with tkinter in the app >> code. I didn't write the (1600 line) program, but certainly am modifying it. >> > Do you run it with python or pythonw, that might also make a difference. > > HTH, > > Alan G. > > > -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From kent37 at tds.net Sat Feb 13 19:57:21 2010 From: kent37 at tds.net (Kent Johnson) Date: Sat, 13 Feb 2010 13:57:21 -0500 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> Message-ID: <1c2a2c591002131057g316ebf5dtb824e9c4504cdae5@mail.gmail.com> On Sat, Feb 13, 2010 at 10:56 AM, patrice laporte wrote: > Being in an exeption of my own, I want to print the name of the caller, and > I'm looking for a way to have it. > > I've found a lot of recipe all of them using what seems to be, according to > me, a not so good trick : all those recipe make use of > sys._getframe(1).f_code.co_name > > A closer look at the documentation about sys._getframe at > http://docs.python.org/library/sys.html make me think it's not a good idea, > because of the note : > "CPython implementation detail: This function should be used for internal > and specialized purposes only. It is not guaranteed to exist in all > implementations of Python." > > So, this trick works today, but what about tomorow ? > > Is anybody have an idea how to get the the same result without _getframe ? Here is a way to do it using the traceback module. Under the hood it is still using implementation details contained in traceback and stack frame objects but the public interface in the traceback module should be stable. import sys, traceback def whoami(): stack = traceback.extract_stack(limit=2) print "Who call me ? : ", stack[0][2] print "Who am I ? : ", stack[1][2] def print_caller_name(): whoami() if __name__ == "__main__": print_caller_name() Kent From david at pythontoo.com Sat Feb 13 19:58:34 2010 From: david at pythontoo.com (David Abbott) Date: Sat, 13 Feb 2010 13:58:34 -0500 Subject: [Tutor] operators >> and & Message-ID: <1266087514.23188.6.camel@opteron.dwabbott.com> I am attempting to understand this little program that converts a network byte order 32-bit integer to a dotted quad ip address. #!/usr/bin/python # Filename : int2ip.py MAX_IP = 0xffffffffL ip = 2130706433 def int2ip(l): if MAX_IP < l < 0: raise TypeError, "expected int between 0 and %d inclusive" % MAX_IP return '%d.%d.%d.%d' % (l>>24 & 255, l>>16 & 255, l>>8 & 255, l & 255) result = int2ip(ip) print result I don't understand the l>>24 & 255. from the docs; Right Shift a >> b rshift(a, b) Bitwise And a & b and_(a, b) thanks -- David Abbott From steve at alchemy.com Sat Feb 13 20:32:56 2010 From: steve at alchemy.com (Steve Willoughby) Date: Sat, 13 Feb 2010 11:32:56 -0800 Subject: [Tutor] operators >> and & In-Reply-To: <1266087514.23188.6.camel@opteron.dwabbott.com> References: <1266087514.23188.6.camel@opteron.dwabbott.com> Message-ID: <20100213193256.GA48938@dragon.alchemy.com> On Sat, Feb 13, 2010 at 01:58:34PM -0500, David Abbott wrote: > I don't understand the l>>24 & 255. The >> and << operators (when applied to integers) shift the bits left or right a number of positions. The number 5, for example, is 101 in binary, or if you want to picture that as a 16-bit value, 0000000000000101. When you do 5 << 3 that takes those bits and shifts them 3 places to the left, so you end up with: 0000000000101000 The >> works similarly but shifting to the right. The & operator performs a logical "AND" to the individual bits of two numbers, where A & B is 1 if A and B are both 1 and 0 otherwise. People often use them for "masking" out a set of bits from a bigger value, like this. To get just the least significant octet from an IP address like 1.2.3.4, you would AND it with 255 (0xff) like so: ip = 00000001000000100000001100000100 # 1.2.3.4 0xff= 00000000000000000000000011111111 & -------------------------------- 00000000000000000000000000000100 # 4 Then you can shift 8 places right and AND again to get the next octet: ip = 00000001000000100000001100000100 # 1.2.3.4 >>8= 00000000000000010000001000000011 # 0.1.2.3 0xff= 00000000000000000000000011111111 & -------------------------------- 00000000000000000000000000000011 # 3 -- Steve Willoughby | Using billion-dollar satellites steve at alchemy.com | to hunt for Tupperware. From zepangolin at gmail.com Sat Feb 13 20:38:45 2010 From: zepangolin at gmail.com (patrice laporte) Date: Sat, 13 Feb 2010 20:38:45 +0100 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: <1c2a2c591002131057g316ebf5dtb824e9c4504cdae5@mail.gmail.com> References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> <1c2a2c591002131057g316ebf5dtb824e9c4504cdae5@mail.gmail.com> Message-ID: <954757881002131138l247cee3bjc42b26cc68a841ce@mail.gmail.com> 2010/2/13 Kent Johnson > > > >Here is a way to do it using the traceback module. Under the hood it > >is still using implementation details contained in traceback and stack > >frame objects but the public interface in the traceback module should > >be stable. > > >import sys, traceback > > >def whoami(): > > stack = traceback.extract_stack(limit=2) > > print "Who call me ? : ", stack[0][2] > > print "Who am I ? : ", stack[1][2] > > >def print_caller_name(): > > whoami() > > >if __name__ == "__main__": > > print_caller_name() > > >Kent > Thanks for the help, I will look closer at the traceback module and at your solution Patrice -------------- next part -------------- An HTML attachment was scrubbed... URL: From waynejwerner at gmail.com Sat Feb 13 20:45:52 2010 From: waynejwerner at gmail.com (Wayne Werner) Date: Sat, 13 Feb 2010 13:45:52 -0600 Subject: [Tutor] operators >> and & In-Reply-To: <1266087514.23188.6.camel@opteron.dwabbott.com> References: <1266087514.23188.6.camel@opteron.dwabbott.com> Message-ID: <333efb451002131145s5fbfcc0an76df01e8f950aa68@mail.gmail.com> On Sat, Feb 13, 2010 at 12:58 PM, David Abbott wrote: > > I don't understand the l>>24 & 255. > > from the docs; > Right Shift a >> b rshift(a, b) > Bitwise And a & b and_(a, b) > They're binary operations... If you're not familiar, wikipedia or google can find you many sources. In a nutshell: 0110 >> 1 == 0011 0011 >> 1 == 0001 0110 & 0101 == 0100 0100 & 0001 == 0000 HTH, Wayne -------------- next part -------------- An HTML attachment was scrubbed... URL: From david at pythontoo.com Sat Feb 13 21:51:08 2010 From: david at pythontoo.com (David Abbott) Date: Sat, 13 Feb 2010 15:51:08 -0500 Subject: [Tutor] operators >> and & In-Reply-To: <20100213193256.GA48938@dragon.alchemy.com> References: <1266087514.23188.6.camel@opteron.dwabbott.com> <20100213193256.GA48938@dragon.alchemy.com> Message-ID: <1266094268.28047.9.camel@opteron.dwabbott.com> On Sat, 2010-02-13 at 11:32 -0800, Steve Willoughby wrote: On Sat, 2010-02-13 at 13:45 -0600, Wayne Werner wrote: Thanks Steve and Wayne your explanations; HAL (helps a lot) -- David Abbott From shurui91 at gmail.com Sat Feb 13 22:08:05 2010 From: shurui91 at gmail.com (=?GB2312?B?wfXK6e6j?=) Date: Sat, 13 Feb 2010 16:08:05 -0500 Subject: [Tutor] ask Message-ID: <2b9003cf1002131308t6ff53396m38cd201a4557d92c@mail.gmail.com> Here are my assignment about Python, I don't know if anything is wrong. Is there anybody can help me? 1. assignment 9a and 9b hyperlink: http://cset.sp.utoledo.edu/cset1100py/cset1100_assign.html#simplepy 2. I don't know how to run a program in putty.exe, who knows? Cause i don't know the relationship between putty.exe and python. Thank you! Aaron -------------- next part -------------- An HTML attachment was scrubbed... URL: From kent37 at tds.net Sat Feb 13 22:33:59 2010 From: kent37 at tds.net (Kent Johnson) Date: Sat, 13 Feb 2010 16:33:59 -0500 Subject: [Tutor] ask In-Reply-To: <2b9003cf1002131308t6ff53396m38cd201a4557d92c@mail.gmail.com> References: <2b9003cf1002131308t6ff53396m38cd201a4557d92c@mail.gmail.com> Message-ID: <1c2a2c591002131333o5791b5d5ud2b25052e8308d04@mail.gmail.com> On Sat, Feb 13, 2010 at 4:08 PM, ??? wrote: > Here are my assignment about Python, I don't know if anything is wrong. Is > there anybody can help me? > > 1. assignment 9a and 9b hyperlink: > > http://cset.sp.utoledo.edu/cset1100py/cset1100_assign.html#simplepy > > 2. I don't know how to run a program in putty.exe, who knows? Cause i don't > know the relationship between putty.exe and python. These assignments are more about learning your local computing environment and tools than they are about Python. If you are having trouble you should ask for help at school. Kent From rabidpoobear at gmail.com Sat Feb 13 22:38:57 2010 From: rabidpoobear at gmail.com (Luke Paireepinart) Date: Sat, 13 Feb 2010 15:38:57 -0600 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> Message-ID: On Sat, Feb 13, 2010 at 9:56 AM, patrice laporte wrote: > > Hi, > > Being in an exeption of my own, I want to print the name of the caller, and > I'm looking for a way to have it. > > Could you tell us exactly why you want to do this? It seems sort of strange. Also couldn't you pass the caller as an argument to your function? -------------- next part -------------- An HTML attachment was scrubbed... URL: From shurui91 at gmail.com Sat Feb 13 22:40:18 2010 From: shurui91 at gmail.com (Shurui Liu (Aaron Liu)) Date: Sat, 13 Feb 2010 16:40:18 -0500 Subject: [Tutor] ask In-Reply-To: <1c2a2c591002131333o5791b5d5ud2b25052e8308d04@mail.gmail.com> References: <2b9003cf1002131308t6ff53396m38cd201a4557d92c@mail.gmail.com> <1c2a2c591002131333o5791b5d5ud2b25052e8308d04@mail.gmail.com> Message-ID: <2b9003cf1002131340v16e843fah13e3ed0d1db9ddc9@mail.gmail.com> Yeah, i know. I don't want somebody tell me all the answers of these assignment directly. I just want to know is there any error in the commands listed online? My teacher told us there is some, but I cannot find out. He said we can run them on putty.exe as soon as we fix the errors. I have found some format error, but still "command not found" Thank you! 2010/2/13 Kent Johnson > On Sat, Feb 13, 2010 at 4:08 PM, ??? wrote: > > Here are my assignment about Python, I don't know if anything is wrong. > Is > > there anybody can help me? > > > > 1. assignment 9a and 9b hyperlink: > > > > http://cset.sp.utoledo.edu/cset1100py/cset1100_assign.html#simplepy > > > > 2. I don't know how to run a program in putty.exe, who knows? Cause i > don't > > know the relationship between putty.exe and python. > > These assignments are more about learning your local computing > environment and tools than they are about Python. If you are having > trouble you should ask for help at school. > > Kent > -- Shurui Liu (Aaron Liu) Computer Science & Engineering Technology University of Toledo -------------- next part -------------- An HTML attachment was scrubbed... URL: From kent37 at tds.net Sat Feb 13 23:04:41 2010 From: kent37 at tds.net (Kent Johnson) Date: Sat, 13 Feb 2010 17:04:41 -0500 Subject: [Tutor] ask In-Reply-To: <2b9003cf1002131340v16e843fah13e3ed0d1db9ddc9@mail.gmail.com> References: <2b9003cf1002131308t6ff53396m38cd201a4557d92c@mail.gmail.com> <1c2a2c591002131333o5791b5d5ud2b25052e8308d04@mail.gmail.com> <2b9003cf1002131340v16e843fah13e3ed0d1db9ddc9@mail.gmail.com> Message-ID: <1c2a2c591002131404x63de5da1j77c2cdf88b5e910d@mail.gmail.com> 2010/2/13 Shurui Liu (Aaron Liu) : > Yeah, i know. I don't want somebody tell me all the answers of these > assignment directly. I just want to know is there any error in the commands > listed online? My teacher told us there is some, but I cannot find out. He > said we can run them on putty.exe as soon as we fix the errors. I have found > some format error, but still "command not found" Thank you! We can help you with Python homework if you have specific questions, but don't ask us to do the homework for you. The point of the assignment seems to be for you to learn to run Python programs and find and fix errors. Putty is a ssh client that will help you run programs on a server, but you should be able to try running the programs on your own computer first. Kent From denis.spir at free.fr Sat Feb 13 23:17:27 2010 From: denis.spir at free.fr (spir) Date: Sat, 13 Feb 2010 23:17:27 +0100 Subject: [Tutor] operators >> and & In-Reply-To: <1266087514.23188.6.camel@opteron.dwabbott.com> References: <1266087514.23188.6.camel@opteron.dwabbott.com> Message-ID: <20100213231727.7f08b984@o> On Sat, 13 Feb 2010 13:58:34 -0500 David Abbott wrote: > I am attempting to understand this little program that converts a > network byte order 32-bit integer to a dotted quad ip address. > > #!/usr/bin/python > # Filename : int2ip.py > > MAX_IP = 0xffffffffL > ip = 2130706433 > > def int2ip(l): > if MAX_IP < l < 0: > raise TypeError, "expected int between 0 and %d inclusive" % > MAX_IP > return '%d.%d.%d.%d' % (l>>24 & 255, l>>16 & 255, l>>8 & 255, l & > 255) > > result = int2ip(ip) > print result > > I don't understand the l>>24 & 255. > > from the docs; > Right Shift a >> b rshift(a, b) > Bitwise And a & b and_(a, b) > > thanks > In addition to Steve's excellent explanation: Shifting to the left n bits is equivalent to multiplying by 2^n. Shifting to the right n bits is equivalent to dividing by 2^n. Shifting to the right 8 bits is thus equivalent to dividing by 2^8=256; which means making each octet (in a long integer) one level less significant. AND-ing is equivalent to masking (this is actually called a mask operating) all bits wich are not 1 in the mask. So AND-ing with 11111111=255 masks all bits except the ones of the least significant octet. If you represent a 32-bit integer as 4 octets, or 8 hex digits, the picture is easier to catch: n = 0x12345678 # 0x12345678 = abcd (b=0x34=52) # to get b: temp = n >> 16 # 0x00001234 = 00ab b = temp & 255 # 0x00000034 = 000b You can perform the same operation without bit-level operators, using modulo and integer division. To understand this, again consider the "abcd" representation: this means a 32-bit integer can be seen as 4-digit number written in base 256 (yes!). Division by 256^n gets rid of n lowest digits, moving down all other ones. Modulo 256^n gets rid of digits in higher position than n. (This may help and fully catch the sense of "base n"). n = 0x12345678 # 0x12345678 = abcd (b=0x34) # to get b: temp = n // (256**2) # 0x00001234 = 00ab b = temp % 256 # 0x00000034 = 000b (examples untested) Bit operations are by far faster, indeed. Denis ________________________________ la vita e estrany http://spir.wikidot.com/ From denis.spir at free.fr Sat Feb 13 23:28:31 2010 From: denis.spir at free.fr (spir) Date: Sat, 13 Feb 2010 23:28:31 +0100 Subject: [Tutor] operators >> and & In-Reply-To: <20100213231727.7f08b984@o> References: <1266087514.23188.6.camel@opteron.dwabbott.com> <20100213231727.7f08b984@o> Message-ID: <20100213232831.5c1c1d83@o> On Sat, 13 Feb 2010 23:17:27 +0100 spir wrote: > On Sat, 13 Feb 2010 13:58:34 -0500 > David Abbott wrote: > > > I am attempting to understand this little program that converts a > > network byte order 32-bit integer to a dotted quad ip address. > > > > #!/usr/bin/python > > # Filename : int2ip.py > > > > MAX_IP = 0xffffffffL > > ip = 2130706433 > > > > def int2ip(l): > > if MAX_IP < l < 0: > > raise TypeError, "expected int between 0 and %d inclusive" % > > MAX_IP > > return '%d.%d.%d.%d' % (l>>24 & 255, l>>16 & 255, l>>8 & 255, l & > > 255) PS: in "l>>24 & 255", the & operation is useless, since all 24 higher bits are already thrown away by the shift: >>> 0x12345678 >> 24 18 # = 0x12 Denis ________________________________ la vita e estrany http://spir.wikidot.com/ From alan.gauld at btinternet.com Sun Feb 14 00:54:24 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Sat, 13 Feb 2010 23:54:24 -0000 Subject: [Tutor] operators >> and & References: <1266087514.23188.6.camel@opteron.dwabbott.com> Message-ID: "David Abbott" wrote > I am attempting to understand this little program that converts a > network byte order 32-bit integer to a dotted quad ip address. > def int2ip(l): > if MAX_IP < l < 0: > raise TypeError, "expected int between 0 and %d inclusive" % > MAX_IP > return '%d.%d.%d.%d' % (l>>24 & 255, l>>16 & 255, l>>8 & 255, l & > 255) The >>> shifts the number bitwise to the right. Thus the number 8 is 1000 in binary 8 >> 3 -> 0001 So taking a 32 bit number and shifting it right 24 bits leaves the top 8 bits N & 255 uses a bitwise and to filter the number N by removing anything outside the 8 bits (should any spurious 1's sneak in...) In bitwise and a 1 and 1 gives 1 any other combination gives 0. So and'ing with 255 (11111111) simply repeats the 8 bits of N while zeroing all the other bits. Similarly >> 16 gets the top 16 bits and andintg with 255 processes bits 16-24 and zeros the rest. And so on for the other two groups of 8 bits. There is more on using bitwise operators and "masking" in my Using the OS topic in my tutorial(v2). (Look for a "sidebar" half way down) HTH, -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From alan.gauld at btinternet.com Sun Feb 14 00:58:10 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Sat, 13 Feb 2010 23:58:10 -0000 Subject: [Tutor] operators >> and & References: <1266087514.23188.6.camel@opteron.dwabbott.com><20100213231727.7f08b984@o> <20100213232831.5c1c1d83@o> Message-ID: "spir" wrote > PS: in "l>>24 & 255", the & operation is useless, since all 24 higher > bits are already thrown away by the shift: They are not gone however there are still 32 bits in an integer so the top bits *should* be set to zero. But glitches can occur from time to time... It is good practice to restrict the range to the 8 bits needed by and'ing with 255 even when you think you should be safe. -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From steve at pearwood.info Sun Feb 14 01:41:41 2010 From: steve at pearwood.info (Steven D'Aprano) Date: Sun, 14 Feb 2010 11:41:41 +1100 Subject: [Tutor] aliasing an imported module In-Reply-To: <0A04999D-5173-4355-A1E6-1BAD757DC2BD@newcastle.edu.au> References: <0A04999D-5173-4355-A1E6-1BAD757DC2BD@newcastle.edu.au> Message-ID: <201002141141.41510.steve@pearwood.info> On Sat, 13 Feb 2010 10:51:38 am Garry Willgoose wrote: > I want to be able to import multiple instances of a module and call > each by a unique name and it doesn't appear at first glance that > either import or __import__ have what I need. No, such a thing is not officially supported by Python. Python treats modules as singletons -- there is only one instance of any module at any time. It is possible to force Python to break that promise, but that is fighting the language, and there's no guarantee that it won't cause other breakages further along. So if you choose to create multiple instances of a module, you're doing something the language doesn't want you to do, and if you end up shooting yourself in the foot you'll have no one to blame but yourself. Having said that, the following trick should do what you want. Start with a simple module holding state: # mymodule.py state = [] Here's Python's normal behaviour: >>> import mymodule >>> mymodule.state [] >>> mymodule.state.append(123) >>> mymodule.state [123] >>> import mymodule as something_else >>> something_else.state [123] And here's the trick: >>> import sys >>> del sys.modules['mymodule'] >>> import mymodule as another_name >>> another_name.state [] >>> mymodule.state # Check the original. [123] This *should* work across all versions and implementations of Python, but remember that it's a hack. You're fighting the language rather than working with it. Another problem is that there's no guarantee that the module holds all its state inside itself: it might in turn import a second module, and store state in there. Many packages, in particular, may do this. The best solution is to avoid global state if you possibly can. You also say: > The key problem is that ? > the ?module might locally store some partial results ready for the ? > next time its called to save CPU time (typically the results for one ? > timestep ready for the next timestep). I'm going to take a wild guess as to what you're doing, and make a suggestion for how you can do something better. I guess you have functions something like this: STATE = None def func(): global STATE if STATE is None: # No global state recorded, so we start from scratch. step = 1 partial = 0 else: step, partial = STATE step += 1 partial = do_some_calculations(step, partial) STATE = (step, partial) return partial But as you point out, that means all calls to func() use the same global state. Here are two alternatives. Here's a rather messy one, but it tickles my fancy: use a token to identify the caller, so each caller gets their own state and not somebody else's. LAST_TOKEN = 0 def get_token(): global LAST_TOKEN LAST_TOKEN += 1 return LAST_TOKEN STATE = {} def func(token): global STATE if not STATE[token]: # No global state recorded, so we start from scratch. step = 1 partial = 0 else: step, partial = STATE[token] step += 1 partial = do_some_calculations(step, partial) # Defined elsewhere. STATE[token] = (step, partial) return partial Then, before each independent use of func, the caller simply calls get_token() and passes that to the function. I'm sure you can see problems with this: - the caller has to store their tokens and make sure they pass the right one; - the function needs to deal with invalid tokens; - the global STATE ends up storing the result of intermediate calculations long after they are no longer needed; - the separation is a "gentleman's agreement" -- there is nothing stopping one caller from guessing another valid token. Although I'm remarkably fond of this solution in theory, in practice I would never use it. A better solution is to write func in a more object-oriented fashion: class FuncCalculator(object): """Class that calculates func""" def __init__(self): # Start with initial state. self.STATE = (1, 0.0) def __call__(self): step, partial = self.STATE step += 1 partial = self.do_some_calculations(step, partial) self.STATE = (step, partial) return partial def do_some_calculations(self, step, partial): return partial + 1.0/step # or whatever Instances of the class are callable as if they were functions. In C++ terminology, this is called a "functor". In Python, we normally just call it a callable. So we can create as many independent "functions" as needed, each with their own state: >>> f = FuncCalculator() >>> g = FuncCalculator() >>> h = FuncCalculator() >>> f() 0.5 >>> f() 0.83333333333333326 >>> f() 1.0833333333333333 >>> g() 0.5 >>> g() 0.83333333333333326 >>> h() 0.5 >>> f() 1.2833333333333332 Hope this helps! -- Steven D'Aprano From eduardo.susan at gmail.com Sun Feb 14 02:02:45 2010 From: eduardo.susan at gmail.com (Eduardo Vieira) Date: Sat, 13 Feb 2010 18:02:45 -0700 Subject: [Tutor] Not understanding this code example. Help, please. In-Reply-To: <1c2a2c591002130659h4e3f40cfh5cc304f5c53397e4@mail.gmail.com> References: <9356b9f31002122049w5cde73cbqb8c1f231367bd15a@mail.gmail.com> <1c2a2c591002130659h4e3f40cfh5cc304f5c53397e4@mail.gmail.com> Message-ID: <9356b9f31002131702x72364500l21a0b2c080a59e57@mail.gmail.com> On Sat, Feb 13, 2010 at 7:59 AM, Kent Johnson wrote: > On Fri, Feb 12, 2010 at 11:49 PM, Eduardo Vieira > wrote: >> Hello! I was reading the latest version of Mark Pilgrim's "Dive into >> Python" and am confused with these example about the pluralization >> rules. See http://diveintopython3.org/examples/plural3.py and >> http://diveintopython3.org/generators.html#a-list-of-patterns >> Here is part of the code: >> import re >> >> def build_match_and_apply_functions(pattern, search, replace): >> ? ?def matches_rule(word): >> ? ? ? ?return re.search(pattern, word) >> ? ?def apply_rule(word): >> ? ? ? ?return re.sub(search, replace, word) >> ? ?return (matches_rule, apply_rule) >> >> patterns = \ >> ?( >> ? ?('[sxz]$', ? ? ? ? ? '$', ?'es'), >> ? ?('[^aeioudgkprt]h$', '$', ?'es'), >> ? ?('(qu|[^aeiou])y$', ?'y$', 'ies'), >> ? ?('$', ? ? ? ? ? ? ? ?'$', ?'s') >> ?) >> rules = [build_match_and_apply_functions(pattern, search, replace) >> ? ? ? ? for (pattern, search, replace) in patterns] >> >> def plural(noun): >> ? ?for matches_rule, apply_rule in rules: >> ? ? ? ?if matches_rule(noun): >> ? ? ? ? ? ?return apply_rule(noun) >> >> this example works on IDLE: print plural("baby") >> My question is "baby" assigned to "word" in the inner function? It's a >> little mind bending for me... > > It is a little mind bending when you first start seeing functions used > as first-class objects. In Python functions are values that can be > passed as arguments, returned, and assigned just like any other value. > This can simplify a lot of problems. > > In this case I think the use of functions makes the code needlessly > complicated. Without build_match_and_apply_functions() and the rules > list it would look like this: > > def plural(noun): > ? for (pattern, search, replace) in patterns: > ? ? ? if re.search(pattern, noun): > ? ? ? ? ? return re.replace(search, replace, noun) > > which is not much longer that the original plural(), doesn't require > all the helper machinery and IMO is easier to understand. > > Kent > Thanks for the input. Yes, there are simple ways to do it. If I recall the author shows 3 or 4 different ways of doing this, each showing some of python's features. This one was to introduce the concept of closures. Cheers, Eduardo From steve at pearwood.info Sun Feb 14 02:21:49 2010 From: steve at pearwood.info (Steven D'Aprano) Date: Sun, 14 Feb 2010 12:21:49 +1100 Subject: [Tutor] operators >> and & In-Reply-To: References: <1266087514.23188.6.camel@opteron.dwabbott.com> <20100213232831.5c1c1d83@o> Message-ID: <201002141221.49429.steve@pearwood.info> On Sun, 14 Feb 2010 10:58:10 am Alan Gauld wrote: > "spir" wrote > > > PS: in "l>>24 & 255", the & operation is useless, since all 24 > > higher bits are already thrown away by the shift: > > They are not gone however there are still 32 bits in an integer so > the top bits *should* be set to zero. No, Python ints are not 32 bit native ints. They're not even 64 bit ints. Python has unified the old "int" type with "long", so that ints automatically grow as needed. This is in Python 3.1: >>> (0).bit_length() 0 >>> (1).bit_length() 1 >>> (2).bit_length() 2 >>> (3).bit_length() 2 >>> (10**100).bit_length() 333 Consequently, if you have an arbitrary int that you don't know where it came from, you can't make any assumptions about the number of bits it uses. > But glitches can occur from time to time... If Python had a glitch of the magnitude of right-shifting non-zero bits into a number, that would be not just a bug but a HUGE bug. That would be as serious as having 1+1 return 374 instead of 2. Guarding against (say) 8 >> 1 returning anything other than 4 makes as much sense as guarding against 8//2 returning something other than 4: if you can't trust Python to get simple integer arithmetic right, then you can't trust it to do *anything*, and your guard (ANDing it with 255) can't be trusted either. > It is good practice to restrict the range to the 8 bits needed by > and'ing with 255 > even when you think you should be safe. It is certainly good practice if you are dealing with numbers which might be more than 24 bits to start with: >>> n = 5**25 >>> n >> 24 17763568394 >>> n >> 24 & 255 10 But *if* you know the int is no more than 32 bits, then adding in a guard to protect against bugs in the >> operator is just wasting CPU cycles and needlessly complicating the code. The right way to guard against "this will never happen" scenarios is with assert: assert n.bit_length() <= 32 # or "assert 0 <= n < 2**32" print(n >> 24) This has two additional advantages: (1) It clearly signals to the reader what your intention is ("I'm absolutely 100% sure than n will not be more than 32 bits, but since I'm a fallible human, I'd rather find out about an error in my logic as soon as possible"). (2) If the caller cares enough about speed to object to the tiny little cost of the assertion, he or she can disable it by passing the -O (O for Optimise) switch to Python. (More likely, while each assert is very cheap, a big application might have many, many asserts.) -- Steven D'Aprano From steve at pearwood.info Sun Feb 14 03:08:51 2010 From: steve at pearwood.info (Steven D'Aprano) Date: Sun, 14 Feb 2010 13:08:51 +1100 Subject: [Tutor] Tutor list as pair progamming plush toy In-Reply-To: <1265988784.21902.10.camel@jabbar> References: <1265988784.21902.10.camel@jabbar> Message-ID: <201002141308.51725.steve@pearwood.info> On Sat, 13 Feb 2010 02:33:04 am Mac Ryan wrote: > whenever I get stuck, I begin to write a message to the > list, and in the process of explaining what is the intended behaviour > and outcome of my code, I systematically find the bug by myself. [...] > Does anybody else experience the same? Yes! -- Steven D'Aprano From the7hansons at msn.com Sun Feb 14 02:08:40 2010 From: the7hansons at msn.com (the kids) Date: Sat, 13 Feb 2010 18:08:40 -0700 Subject: [Tutor] asigning class variables Message-ID: Hi, my name is John Paul. I was trying to define a class but I can't make it asign particular objects particular variables at their creation. Please help. John Paul -------------- next part -------------- An HTML attachment was scrubbed... URL: From kent37 at tds.net Sun Feb 14 04:39:25 2010 From: kent37 at tds.net (Kent Johnson) Date: Sat, 13 Feb 2010 22:39:25 -0500 Subject: [Tutor] json file In-Reply-To: <5f3def2d1002131200r2e5a2eb8wc70fb33460767b9e@mail.gmail.com> References: <5f3def2d1002130421q4115c300ic2e38f9726a2c1f@mail.gmail.com> <1c2a2c591002130711t247e2538vce591036a0bf733a@mail.gmail.com> <5f3def2d1002131200r2e5a2eb8wc70fb33460767b9e@mail.gmail.com> Message-ID: <1c2a2c591002131939l99b5e11v32c76682beb70509@mail.gmail.com> On Sat, Feb 13, 2010 at 3:00 PM, Chris Patillo wrote: > Thanks for your response.? i did some research on json.load() and I don't > understand how you extract the data from it.? How do I get just the name and > number from the file? The value returned from json.load() is a Python dictionary. The structure of the dict will be the same as that of your initial data. In your case, the value of the 'records' key is itself a list of dicts containing names and phone numbers. To get the desired data you have to navigate this structure using standard python. Here is an example using your sample data. Note that I use json.loads() because I have the data in a string, rather than a file. import json from pprint import pprint json_data = '''{ "table":"contacts", "records":[ { "name":"John", "phone":"555-555-4444" }, { "name":"Jane", "phone":"555-555-3333" } ] }''' data = json.loads(json_data) pprint(data) for record in data['records']: print record['name'], record['phone'] The output of the program is {u'records': [{u'name': u'John', u'phone': u'555-555-4444'}, ??????????????{u'name': u'Jane', u'phone': u'555-555-3333'}], ?u'table': u'contacts'} John 555-555-4444 Jane 555-555-3333 Kent PS Please Reply All to reply on list. From kent37 at tds.net Sun Feb 14 04:41:59 2010 From: kent37 at tds.net (Kent Johnson) Date: Sat, 13 Feb 2010 22:41:59 -0500 Subject: [Tutor] asigning class variables In-Reply-To: References: Message-ID: <1c2a2c591002131941l5245a9eelf993db7539e2cf55@mail.gmail.com> On Sat, Feb 13, 2010 at 8:08 PM, the kids wrote: > Hi, my name is John Paul. > > I was trying to define a class but I?can't make it asign particular objects > particular variables at their creation.? Please help. It would help to see some details of what you are trying to do. It sounds like you want an __init__() method in your class: In [1]: class Data(object): ...: def __init__(self, a, b): ...: self.a = a ...: self.b = b In [2]: d = Data(1, 2) In [3]: d.a Out[3]: 1 In [4]: d.b Out[4]: 2 In [5]: dd = Data(42, 57) In [6]: dd.a, dd.b Out[6]: (42, 57) Kent From steve at pearwood.info Sun Feb 14 07:53:07 2010 From: steve at pearwood.info (Steven D'Aprano) Date: Sun, 14 Feb 2010 17:53:07 +1100 Subject: [Tutor] asigning class variables In-Reply-To: References: Message-ID: <201002141753.08334.steve@pearwood.info> On Sun, 14 Feb 2010 12:08:40 pm the kids wrote: > Hi, my name is John Paul. > > I was trying to define a class but I can't make it asign particular > objects particular variables at their creation. Please help. > > John Paul I don't quite follow what you mean, it is best if you can show example code and describe what you expect and what you get instead. But first a brief note on terminology. In some other languages, people talk about "class variables" being variables that are part of the class. To me, that's inconsistent with everything else: an int variable holds an int; a string variable holds a string; a list variable holds a list; so a class variable should hold a class. (You might argue, why would you ever need a variable that was a class? As an experience Python programmer, I can tell you such a thing is very, very useful, and far more common than you might think.) Anyway, in Python circles, it is much more common to describe class variables as attributes. Other languages use the term "members", and people who used Apple's Hypercard will remember the term "properties" (but properties in Python are slightly different). Python has two sorts of attributes (class variables, a.k.a. members): * Attributes which are attached to the class itself, and therefore shared by all the instances. These are known as "class attributes". * Much more common is the ordinary sort of attribute that is attached to instances; these are usually known as "instance attributes", or more often, just plain old attributes. You create a class attribute (shared by all instances) by assigning to a name inside the class definition: class K: shared = [] This is now shared between all instances. You create an instance attribute (not shared) by assigning it inside a method, using the usual attribute syntax. The usual place to do this is inside the __init__ method. (Note that __init__ has TWO underscores at both the beginning and end.) class K: shared = [] def __init__(self): self.attribute = [] And in use: >>> a = K() >>> b = K() >>> a.shared.append(23) >>> b.shared [23] >>> a.attribute.append(23) >>> a.attribute [23] >>> b.attribute [] Using class attributes is sometimes tricky, because Python makes it really easy to accidentally hide a class attribute with an instance attribute with the same name, but fortunately having shared data like this is quite rare, so it's unusual to be a problem. Hope this helps, -- Steven D'Aprano From alan.gauld at btinternet.com Sun Feb 14 10:16:18 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Sun, 14 Feb 2010 09:16:18 -0000 Subject: [Tutor] operators >> and & References: <1266087514.23188.6.camel@opteron.dwabbott.com><20100213232831.5c1c1d83@o> <201002141221.49429.steve@pearwood.info> Message-ID: "Steven D'Aprano" wrote >> They are not gone however there are still 32 bits in an integer so >> the top bits *should* be set to zero. > > No, Python ints are not 32 bit native ints. They're not even 64 bit > ints. Python has unified the old "int" type with "long", so that ints > automatically grow as needed. This is in Python 3.1: Valid point but irrelevant to the one I was making which is that the number after shifting is longer than 8 bits. >> But glitches can occur from time to time... > > If Python had a glitch of the magnitude of right-shifting non-zero bits > into a number, that would be not just a bug but a HUGE bug. Bit shifting is machine specific. Some CPUs (the DEC PDP range from memory is an example) will add the carry bit for example, most will not. But you can never be sure unless you know exactly which artchiotecture the program will run on. And of course data can always be corrupted at any time so its always wise to take as many precautions as possibe to keep it clean (although corruption within the CPU itself is, I agree, extremely unlikely) > be as serious as having 1+1 return 374 instead of 2. Guarding against > (say) 8 >> 1 returning anything other than 4 Not if you have a 4 bit processor and the previous opertation set the carry flag. In that case returning 12 would be emminently sensible....and used to be a common assembler trick for recovering from overflow errors. > guarding against 8//2 returning something other than 4: if you can't > trust Python to get simple integer arithmetic right, But ths is not simple integer arithmetic it is bit m,anippulation. You can use bit manipulation to fake arithmetic but they are fundamentally different operations and may not always produce the same results depending on how the designer built it! > trust it to do *anything*, and your guard (ANDing it with 255) can't be > trusted either. Nothing can be trusted 100% on a computer because, as you say the guard might itself be corrupted. Itas all about risk management. But when it comes to bit operations I'd always have at least one extra level of check, whether it be a mask or a checksum. > It is certainly good practice if you are dealing with numbers which > might be more than 24 bits to start with: Its more than good practice there, its essential. > But *if* you know the int is no more than 32 bits, then adding in a > guard to protect against bugs in the >> operator is just wasting CPU It may not be a bug it may be a design feature. Now all modern CPUs behave as you would expect but if you are running on older equipment (or specialised hardware - but that's more unlikely to have Python onboard!) you can never be quite sure how bitwise operations will react at boundary cases. If you know for certainty what the runtime environment will be then you can afford to take a chance. In the case in point the & 255 keeps the coding style consistent and provides an extra measure of protection against unexpected oddities so I would keep it in there. > cycles and needlessly complicating the code. The right way to guard > against "this will never happen" scenarios is with assert: > > assert n.bit_length() <= 32 # or "assert 0 <= n < 2**32" I would accept the second condition but the mask is much faster. bit_length doesn't seem to work on any of my Pythons (2.5,2.6 and 3.1) > This has two additional advantages: > > (1) It clearly signals to the reader what your intention is ("I'm > absolutely 100% sure than n will not be more than 32 bits, but since > I'm a fallible human, I'd rather find out about an error in my logic as > soon as possible"). The assert approach is perfectly valid, but since the mask is more consistent I'd still prefer to use it in this case. Alan G. From steve at alchemy.com Sun Feb 14 10:33:56 2010 From: steve at alchemy.com (Steve Willoughby) Date: Sun, 14 Feb 2010 01:33:56 -0800 Subject: [Tutor] operators >> and & In-Reply-To: References: <201002141221.49429.steve@pearwood.info> Message-ID: <20100214093356.GA87164@dragon.alchemy.com> On Sun, Feb 14, 2010 at 09:16:18AM -0000, Alan Gauld wrote: > But ths is not simple integer arithmetic it is bit m,anippulation. > You can use bit manipulation to fake arithmetic but they are > fundamentally different operations and may not always > produce the same results depending on how the designer > built it! And this brings us back to one of Python's philosophical points. State clearly and explicitly what you mean to be doing. If you are doing bit manipulation, use bit manipulation operators. All the valid points above in this thread aside, it will make maintain- ing your code easier in the future if it's very clear what you intended the code to accomplish, and how. -- Steve Willoughby | Using billion-dollar satellites steve at alchemy.com | to hunt for Tupperware. From amit.pureenergy at gmail.com Sun Feb 14 12:10:17 2010 From: amit.pureenergy at gmail.com (Amit Sethi) Date: Sun, 14 Feb 2010 16:40:17 +0530 Subject: [Tutor] Editing html using python Message-ID: Hi I need to edit html programmatically . Sadly the html might be broken at places . I was using BeautifulSoup but there were lots of problems and it is also not maintained can some one guide me to any tutorials on editing html using lxml . -- A-M-I-T S|S -------------- next part -------------- An HTML attachment was scrubbed... URL: From zepangolin at gmail.com Sun Feb 14 12:33:09 2010 From: zepangolin at gmail.com (patrice laporte) Date: Sun, 14 Feb 2010 12:33:09 +0100 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> Message-ID: <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> 2010/2/13 Luke Paireepinart > > > On Sat, Feb 13, 2010 at 9:56 AM, patrice laporte wrote: > >> >> Hi, >> >> Being in an exeption of my own, I want to print the name of the caller, >> and I'm looking for a way to have it. >> >> Could you tell us exactly why you want to do this? It seems sort of > strange. Also couldn't you pass the caller as an argument to your function? > > Hi, I don't know if it's strange, maybe, so tell me why. Or maybe it's me.... Maybe the fact I'm ? pure C coder for a longtime prevent me from thinking in Python, maybe my brain is only capable of thinking and viewing in C..... and maybe there's an obvious way to solve my problem that I can't see yet... or maybe it's because I'm French, genetically programed to live in the past ? ... so this mailing list is my starting point to improve my Python understanding. And now, something different : what I want to do, and why. I got a class that takes a file name in its __init__ method (it could be elsewhere, but why not here ?). Then, somewhere in that class, a method will do something with that file name, such as "try to open that file". If the file do esn't exist, bing ! I got an exception "I/O Error n?2 : file doesn't exist". That's nice, I of course catch this exception, but it's not enough for the user : What file are we talking about ? And how to tell the user what is that file, and make him understand he tell the app to use a file that doesn't exist ? And this is not enough for developer : where that error happened ? what class ? what method ? There is many solution, and mine is : - don't check for the existence of the file in __init__ - don't use a default value for the file name parameter in __init__ : coder MUST provide it. - try/catch open(this_file_name) and if I got an IOErro exception, I re-raise my own exception with : - the name of the class where that IOError occured - the name of the method in that class that make that error occured - the name of the file the method tried to opened - some other info to help diagnostic Then my exception object can : - log in a file dedicated to the team (so, just me for the moment) - and/or log in a file dedicated to the user And then the app can popup a message box or something like that. Currently, I'm thinking about "how to get that class/method name", easily, and make something usefull with that. I don't want to write the name of the method and the class each time I need to use my exception class, and I don't want to modify that name each time I'm doing a refactoring operation : I just want to do something like : except IOError, (errno, errmes): raise myexceptioniwanttobenice ("IO Error %d -> %s ('%s')" % (errno, errmes, self.__csv) ) And then I print somewhere a message like : Error in csv2db.getColumnFromCsv : IO Error 2 -> No such file or directory ('toto') What I don't want is to write something like : except IOError, (errno, errmes): raise myexceptioniwanttobenice ("cvs2db.getColumnFromCsv IO Error %d -> %s ('%s')" % (errno, errmes, self.__csv) ) I don't want because it's to much to write, and if I change the class name, I don't want to rewrite all my call to change that name. So, I was looking for a way to retrieve : The name of the class the object that throw the exception belongs to The name of the method in that class And I finally found those recipe with the sys._getframe call. My first solution, currently, is (I didn't yet rewrite it with the solution with the traceback module) : class argError(Exception): def __init__(self, callerClass, errorMessage): self.__class = callerClass.__class__.__name__ self.__method = sys._getframe(1).f_code.co_name self.__message = errorMessage def __str__(self): return "Error in %s.%s : %s" % (self.__class, self.__method, self.__message) And how I use it : try: f = open(self.__csv) except IOError, (errno, errmes): raise argError (self, "IO Error %d -> %s ('%s')" % (errno, errmes, self.__csv) ) I now will : - rewrite it with the solution with traceback module - read about that module and find how to get rid of the need to pass "self" as an argument in the call "raise argError (*self*, "IO Error %d -> %s ('%s')" % (errno, errmes, self.__csv) )". That call enable me to get the name of the class. All of that is a way to me to experiment Python, I try a lot of thing to understand, and then I will make a choice. But now, it's time to lunch. Did I gave you enough information about what I want ? Patrice -------------- next part -------------- An HTML attachment was scrubbed... URL: From rabidpoobear at gmail.com Sun Feb 14 13:10:20 2010 From: rabidpoobear at gmail.com (Luke Paireepinart) Date: Sun, 14 Feb 2010 06:10:20 -0600 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> Message-ID: I see why you would want the error messages but why is the default error message not enough, that is why I am curious, and typically introspection on objects is not necessary (for example, people often want to convert a string into a variable name to store a value (say they have the string "foobar1" and they want to store the value "f" in the variable "foobar1", how do they change foobar1 to reference a string? well you can just use exec but the core issue is that there's really no reason to do it in the first place, they can just use a dictionary and store dict['foobar1'] = 'f' and it is functionally equivalent (without the danger in the code)). I get the feeling that your issue is the same sort of thing, where an easier solution exists but for whatever reason you don't see it. I don't know if this is true or not. Here's my take on this: >>> class x(object): def __init__(self, fname): self.temp = open(fname).read() >>> a = x('foobar') Traceback (most recent call last): File "", line 1, in # this is the module it's in a = x('foobar') # this is the line where I tried to initialize it File "", line 3, in __init__ # which called this function, which is the one that has the error self.temp = open(fname).read() #and the error occurred while trying to perform this operation IOError: [Errno 2] No such file or directory: 'foobar' #and the error was that the file 'foobar' could not be found. This is implicitly stated that 'x' is the class with the method that had the issue, and it was specifically the __init__ method, and the file that could not be read was called 'foobar'. How does this not satisfy your requirements? Is it the form of the output that you do not agree with (you want it all on one line?) I've never had issues with Python's exception statements, I've always had no trouble finding where exceptions occurred, and I'm not sure what information is missing from the traceback that you'd like to convey to the user. On Sun, Feb 14, 2010 at 5:33 AM, patrice laporte wrote: > > 2010/2/13 Luke Paireepinart > > >> >> On Sat, Feb 13, 2010 at 9:56 AM, patrice laporte wrote: >> >>> >>> Hi, >>> >>> Being in an exeption of my own, I want to print the name of the caller, >>> and I'm looking for a way to have it. >>> >>> Could you tell us exactly why you want to do this? It seems sort of >> strange. Also couldn't you pass the caller as an argument to your function? >> >> > Hi, > > I don't know if it's strange, maybe, so tell me why. Or maybe it's me.... > Maybe the fact I'm ? pure C coder for a longtime prevent me from thinking in > Python, maybe my brain is only capable of thinking and viewing in C..... and > maybe there's an obvious way to solve my problem that I can't see yet... or > maybe it's because I'm French, genetically programed to live in the past ? > ... so this mailing list is my starting point to improve my Python > understanding. > > And now, something different : what I want to do, and why. > > I got a class that takes a file name in its __init__ method (it could be > elsewhere, but why not here ?). Then, somewhere in that class, a method will > do something with that file name, such as "try to open that file". > > If the file do esn't exist, bing ! I got an exception "I/O Error n?2 : file > doesn't exist". > > That's nice, I of course catch this exception, but it's not enough for the > user : What file are we talking about ? And how to tell the user what is > that file, and make him understand he tell the app to use a file that > doesn't exist ? > And this is not enough for developer : where that error happened ? what > class ? what method ? > > There is many solution, and mine is : > > - don't check for the existence of the file in __init__ > - don't use a default value for the file name parameter in __init__ : coder > MUST provide it. > - try/catch open(this_file_name) and if I got an IOErro exception, I > re-raise my own exception with : > - the name of the class where that IOError occured > - the name of the method in that class that make that error occured > - the name of the file the method tried to opened > - some other info to help diagnostic > > Then my exception object can : > - log in a file dedicated to the team (so, just me for the moment) > - and/or log in a file dedicated to the user > > And then the app can popup a message box or something like that. > > Currently, I'm thinking about "how to get that class/method name", easily, > and make something usefull with that. > > I don't want to write the name of the method and the class each time I need > to use my exception class, and I don't want to modify that name each time > I'm doing a refactoring operation : I just want to do something like : > > except IOError, (errno, errmes): > raise myexceptioniwanttobenice ("IO Error %d -> %s ('%s')" % > (errno, errmes, self.__csv) ) > > And then I print somewhere a message like : > > Error in csv2db.getColumnFromCsv : IO Error 2 -> No such file or > directory ('toto') > > What I don't want is to write something like : > > except IOError, (errno, errmes): > raise myexceptioniwanttobenice ("cvs2db.getColumnFromCsv IO > Error %d -> %s ('%s')" % (errno, errmes, self.__csv) ) > > I don't want because it's to much to write, and if I change the class name, > I don't want to rewrite all my call to change that name. > > So, I was looking for a way to retrieve : > The name of the class the object that throw the exception belongs to > The name of the method in that class > > And I finally found those recipe with the sys._getframe call. > > My first solution, currently, is (I didn't yet rewrite it with the solution > with the traceback module) : > > class argError(Exception): > def __init__(self, callerClass, errorMessage): > self.__class = callerClass.__class__.__name__ > self.__method = sys._getframe(1).f_code.co_name > self.__message = errorMessage > > def __str__(self): > return "Error in %s.%s : %s" % (self.__class, self.__method, > self.__message) > > And how I use it : > > try: > f = open(self.__csv) > except IOError, (errno, errmes): > raise argError (self, "IO Error %d -> %s ('%s')" % (errno, > errmes, self.__csv) ) > > I now will : > - rewrite it with the solution with traceback module > - read about that module and find how to get rid of the need to pass "self" > as an argument in the call "raise argError (*self*, "IO Error %d -> %s > ('%s')" % (errno, errmes, self.__csv) )". That call enable me to get the > name of the class. > > All of that is a way to me to experiment Python, I try a lot of thing to > understand, and then I will make a choice. > > But now, it's time to lunch. Did I gave you enough information about what I > want ? > > Patrice > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From rabidpoobear at gmail.com Sun Feb 14 13:12:33 2010 From: rabidpoobear at gmail.com (Luke Paireepinart) Date: Sun, 14 Feb 2010 06:12:33 -0600 Subject: [Tutor] Editing html using python In-Reply-To: References: Message-ID: On Sun, Feb 14, 2010 at 5:10 AM, Amit Sethi wrote: > Hi I need to edit html programmatically . Sadly the html might be broken at > places . I was using BeautifulSoup but there were lots of problems and it is > also not maintained can some one guide me to any tutorials on editing html > using lxml . > This is a rather specific question and if you really just want tutorials why don't you just google for them? Or are you also asking in a roundabout way if anyone on the list has a better idea for parsing broken html? It would help if you would take the time to explain how the html is broken and what exactly "lost of problems" with BeautifulSoup were. Also I think beautifulsoup is part of the Python standardlib now, isn't it? Why do you think it is not maintained? -------------- next part -------------- An HTML attachment was scrubbed... URL: From kent37 at tds.net Sun Feb 14 14:25:10 2010 From: kent37 at tds.net (Kent Johnson) Date: Sun, 14 Feb 2010 08:25:10 -0500 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> Message-ID: <1c2a2c591002140525k7c47b81ar9efc62b9896cdd7c@mail.gmail.com> On Sun, Feb 14, 2010 at 6:33 AM, patrice laporte wrote: > - try/catch open(this_file_name) and if I got an IOErro exception, I > re-raise my own exception with : > - the name of the class where that IOError occured > - the name of the method in that class that make that error occured > - the name of the file the method tried to opened > - some other info to help diagnostic > > Then my exception object can : > - log in a file dedicated to the team (so, just me for the moment) > - and/or log in a file dedicated to the user > > And then the app can popup a message box or something like that. For simple applications that run from the command line and just do one thing, it is often adequate to let the exceptions propagate to the top level of the program and abort it, printing the stack trace. If the programming is doing some kind of repeated processing and you don't want an error in one iteration to abort the rest of the processing, then catch the exception inthe loop and log the error, then continue. The logging module makes it pretty easy to log exceptions. You can even have it log a detailed error to a file and a shortened version to the console. For GUI programs I usually install an exception handler in the event loop so if there is a problem running any event the error is caught and logged and the program continues. Kent From kent37 at tds.net Sun Feb 14 14:30:37 2010 From: kent37 at tds.net (Kent Johnson) Date: Sun, 14 Feb 2010 08:30:37 -0500 Subject: [Tutor] Editing html using python In-Reply-To: References: Message-ID: <1c2a2c591002140530h54084b13ned63675fa719bfdd@mail.gmail.com> On Sun, Feb 14, 2010 at 6:10 AM, Amit Sethi wrote: > Hi I need to edit html programmatically . Sadly the html might be broken at > places . I was using BeautifulSoup but there were lots of problems and it is > also not maintained can some one guide me to any tutorials on editing html > using lxml . What version of BS are you using? 3.0.8 seems to be the best choice for Python 2.6. Kent From denis.spir at free.fr Sun Feb 14 14:30:51 2010 From: denis.spir at free.fr (spir) Date: Sun, 14 Feb 2010 14:30:51 +0100 Subject: [Tutor] file exception & behaviour (was: Getting caller name...) In-Reply-To: <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> Message-ID: <20100214143051.744f8388@o> On Sun, 14 Feb 2010 12:33:09 +0100 patrice laporte wrote: > 2010/2/13 Luke Paireepinart > > > > > > > On Sat, Feb 13, 2010 at 9:56 AM, patrice laporte wrote: > > > >> > >> Hi, > >> > >> Being in an exeption of my own, I want to print the name of the caller, > >> and I'm looking for a way to have it. > >> > >> Could you tell us exactly why you want to do this? It seems sort of > > strange. Also couldn't you pass the caller as an argument to your function? > > > > > Hi, > > I don't know if it's strange, maybe, so tell me why. Or maybe it's me.... > Maybe the fact I'm ? pure C coder for a longtime prevent me from thinking in > Python, maybe my brain is only capable of thinking and viewing in C..... and > maybe there's an obvious way to solve my problem that I can't see yet... or > maybe it's because I'm French, genetically programed to live in the past ? > ... so this mailing list is my starting point to improve my Python > understanding. > > And now, something different : what I want to do, and why. > > I got a class that takes a file name in its __init__ method (it could be > elsewhere, but why not here ?). Then, somewhere in that class, a method will > do something with that file name, such as "try to open that file". > > If the file do esn't exist, bing ! I got an exception "I/O Error n?2 : file > doesn't exist". > > That's nice, I of course catch this exception, but it's not enough for the > user : What file are we talking about ? And how to tell the user what is > that file, and make him understand he tell the app to use a file that > doesn't exist ? > And this is not enough for developer : where that error happened ? what > class ? what method ? > > There is many solution, and mine is : > > - don't check for the existence of the file in __init__ > - don't use a default value for the file name parameter in __init__ : coder > MUST provide it. > - try/catch open(this_file_name) and if I got an IOErro exception, I > re-raise my own exception with : > - the name of the class where that IOError occured > - the name of the method in that class that make that error occured > - the name of the file the method tried to opened > - some other info to help diagnostic > > Then my exception object can : > - log in a file dedicated to the team (so, just me for the moment) > - and/or log in a file dedicated to the user > > And then the app can popup a message box or something like that. > > Currently, I'm thinking about "how to get that class/method name", easily, > and make something usefull with that. > > I don't want to write the name of the method and the class each time I need > to use my exception class, and I don't want to modify that name each time > I'm doing a refactoring operation : I just want to do something like : > > except IOError, (errno, errmes): > raise myexceptioniwanttobenice ("IO Error %d -> %s ('%s')" % > (errno, errmes, self.__csv) ) > > And then I print somewhere a message like : > > Error in csv2db.getColumnFromCsv : IO Error 2 -> No such file or > directory ('toto') > > What I don't want is to write something like : > > except IOError, (errno, errmes): > raise myexceptioniwanttobenice ("cvs2db.getColumnFromCsv IO > Error %d -> %s ('%s')" % (errno, errmes, self.__csv) ) > > I don't want because it's to much to write, and if I change the class name, > I don't want to rewrite all my call to change that name. > > So, I was looking for a way to retrieve : > The name of the class the object that throw the exception belongs to > The name of the method in that class > > And I finally found those recipe with the sys._getframe call. > > My first solution, currently, is (I didn't yet rewrite it with the solution > with the traceback module) : > > class argError(Exception): > def __init__(self, callerClass, errorMessage): > self.__class = callerClass.__class__.__name__ > self.__method = sys._getframe(1).f_code.co_name > self.__message = errorMessage > > def __str__(self): > return "Error in %s.%s : %s" % (self.__class, self.__method, > self.__message) > > And how I use it : > > try: > f = open(self.__csv) > except IOError, (errno, errmes): > raise argError (self, "IO Error %d -> %s ('%s')" % (errno, > errmes, self.__csv) ) > > I now will : > - rewrite it with the solution with traceback module > - read about that module and find how to get rid of the need to pass "self" > as an argument in the call "raise argError (*self*, "IO Error %d -> %s > ('%s')" % (errno, errmes, self.__csv) )". That call enable me to get the > name of the class. > > All of that is a way to me to experiment Python, I try a lot of thing to > understand, and then I will make a choice. > > But now, it's time to lunch. Did I gave you enough information about what I > want ? > > Patrice First, here is a kind of implementation of your specification. I just wrote it because I had something similar in mind (a file proxy, not the special exception type) and a few time. But this is globally useless. See below more comments. ========== code =============== #!/usr/bin/env python # coding: utf-8 class FileError(Exception): NO_CALLER = "" def __init__(self, name, info, caller=None): if caller is None: caller = FileError.NO_CALLER self.name, self.caller, self.info = name, caller, info def __str__(self): text = "File error in %s.\nTried to open non-existent file '%s'\n%s" \ % (self.caller,self.name,self.info) logFile = open("error.log", 'w') logFile.write(text) logFile.close() return text class File(object): NAME_MESSAGE = "A File must have a name." FILE_MESSAGE = "File '%s' is closed." def __init__(self, name=None): ''' Init name. ''' if name is None: raise ValueError(File.NAME_MESSAGE) self.name = name self.file = None def __str__(self): ''' File output ''' return "File '%s'" %self.name def open(self, mode = 'r', caller=None): ''' (Try to) open actual file. ''' try: self.file = open(self.name, mode) except IOError, e: raise FileError(self.name, str(e), caller) print "%s is open in mode '%s'." %(self,mode) def close(self): ''' Close actual file. ''' if self.file is None: message = File.FILE_MESSAGE %self.name raise ValueError(message) self.file.close print "%s is closed." %self def __getattr__(self, key): ''' Delegate file method to actual file. ''' print "* method: %s" %key return getattr(self.file, key) def content(self): ''' Close actual file. ''' self.open(mode='r') content = self.read() self.close() return content def writeContent(self, content): ''' Close actual file. ''' self.open(mode='w') self.write(content) self.close() def test(): f = File("test.txt") print f f.open() for line in f.readlines(): print line.rstrip() f.close() print f.content() f.writeContent("foo bar baz") f = File("goo.txt") f.open('r', test) test() ================================= ========== output =============== File 'test.txt' File 'test.txt' is open in mode 'r'. * method: readlines foo bar baz File 'test.txt' is closed. File 'test.txt' is open in mode 'r'. * method: read File 'test.txt' is closed. foo bar baz File 'test.txt' is open in mode 'w'. * method: write File 'test.txt' is closed. Traceback (most recent call last): File "__essai__.py", line 73, in test() File "__essai__.py", line 72, in test f.open('r', test) File "__essai__.py", line 38, in open raise FileError(self.name, str(e), caller) __main__.FileError: File error in . Tried to open non-existent file 'goo.txt' [Errno 2] No such file or directory: 'goo.txt' ===================================== I think you do not need any special treatment of files to get all the info you need when errors occur. The file name and caller already appear in python error texts. In other words: FileError is useless: def test2(): f = file("goo.txt", 'r') test2() ==> Traceback (most recent call last): File "__essai__.py", line 77, in test2() File "__essai__.py", line 76, in test2 ************** f = file("goo.txt", 'r') IOError: [Errno 2] No such file or directory: 'goo.txt' But a file wrapper (or rather: a proxy) can be useful, i guess, to get a kind of "potential" File object type that behaves a bit differently, as illustrated above by transparent opening and closing in content() and writeContent() methods. (That's what I wanted to try, and I rather like it.) Denis PS: Les programmeurs fran?ais ne sont pas suppos?s avoir un capital de g?nes diff?rent, former une race ? part; mais il me semble bien pourtant que toi & moi sommes des programmeurs python pas comme les autres. ________________________________ la vita e estrany http://spir.wikidot.com/ From denis.spir at free.fr Sun Feb 14 14:42:05 2010 From: denis.spir at free.fr (spir) Date: Sun, 14 Feb 2010 14:42:05 +0100 Subject: [Tutor] operators >> and & In-Reply-To: <20100213231727.7f08b984@o> References: <1266087514.23188.6.camel@opteron.dwabbott.com> <20100213231727.7f08b984@o> Message-ID: <20100214144205.282cf92e@o> Just reviewed this post and wonder whether the explanation is clear for anyone else as myself ;-) Denis On Sat, 13 Feb 2010 23:17:27 +0100 spir wrote: > On Sat, 13 Feb 2010 13:58:34 -0500 > David Abbott wrote: > > > I am attempting to understand this little program that converts a > > network byte order 32-bit integer to a dotted quad ip address. > > > > #!/usr/bin/python > > # Filename : int2ip.py > > > > MAX_IP = 0xffffffffL > > ip = 2130706433 > > > > def int2ip(l): > > if MAX_IP < l < 0: > > raise TypeError, "expected int between 0 and %d inclusive" % > > MAX_IP > > return '%d.%d.%d.%d' % (l>>24 & 255, l>>16 & 255, l>>8 & 255, l & > > 255) > > > > result = int2ip(ip) > > print result > > > > I don't understand the l>>24 & 255. > > > > from the docs; > > Right Shift a >> b rshift(a, b) > > Bitwise And a & b and_(a, b) > > > > thanks > > > > In addition to Steve's excellent explanation: > Shifting to the left n bits is equivalent to multiplying by 2^n. Shifting to the right n bits is equivalent to dividing by 2^n. Shifting to the right 8 bits is thus equivalent to dividing by 2^8=256; which means making each octet (in a long integer) one level less significant. > AND-ing is equivalent to masking (this is actually called a mask operating) all bits wich are not 1 in the mask. So AND-ing with 11111111=255 masks all bits except the ones of the least significant octet. > If you represent a 32-bit integer as 4 octets, or 8 hex digits, the picture is easier to catch: > n = 0x12345678 # 0x12345678 = abcd (b=0x34=52) > # to get b: > temp = n >> 16 # 0x00001234 = 00ab > b = temp & 255 # 0x00000034 = 000b > > You can perform the same operation without bit-level operators, using modulo and integer division. To understand this, again consider the "abcd" representation: this means a 32-bit integer can be seen as 4-digit number written in base 256 (yes!). Division by 256^n gets rid of n lowest digits, moving down all other ones. Modulo 256^n gets rid of digits in higher position than n. (This may help and fully catch the sense of "base n"). > n = 0x12345678 # 0x12345678 = abcd (b=0x34) > # to get b: > temp = n // (256**2) # 0x00001234 = 00ab > b = temp % 256 # 0x00000034 = 000b > > (examples untested) > Bit operations are by far faster, indeed. > > > Denis ________________________________ la vita e estrany http://spir.wikidot.com/ From denis.spir at free.fr Sun Feb 14 14:46:13 2010 From: denis.spir at free.fr (spir) Date: Sun, 14 Feb 2010 14:46:13 +0100 Subject: [Tutor] operators >> and & In-Reply-To: References: <1266087514.23188.6.camel@opteron.dwabbott.com> <20100213232831.5c1c1d83@o> <201002141221.49429.steve@pearwood.info> Message-ID: <20100214144613.3433139a@o> On Sun, 14 Feb 2010 09:16:18 -0000 "Alan Gauld" wrote: > In the case in point the & 255 keeps the coding style consistent > and provides an extra measure of protection against unexpected > oddities so I would keep it in there. You're right on that, Kent. My comment was rather wrong. Especially for consistent code I would now keep it, too. Denis ________________________________ la vita e estrany http://spir.wikidot.com/ From steve at pearwood.info Sun Feb 14 16:37:37 2010 From: steve at pearwood.info (Steven D'Aprano) Date: Mon, 15 Feb 2010 02:37:37 +1100 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> Message-ID: <201002150237.38504.steve@pearwood.info> On Sun, 14 Feb 2010 10:33:09 pm patrice laporte wrote: > I got a class that takes a file name in its __init__ method (it > could be elsewhere, but why not here ?). Then, somewhere in that > class, a method will do something with that file name, such as "try > to open that file". > > If the file do esn't exist, bing ! I got an exception "I/O Error n?2 > : file doesn't exist". Are you sure? What version of Python are you using? I get a completely different error message: >>> open("no such file.txt", "r") Traceback (most recent call last): File "", line 1, in IOError: [Errno 2] No such file or directory: 'no such file.txt' Note carefully that the exception shows you the file name. > That's nice, I of course catch this exception, but it's not enough > for the user : What file are we talking about ? And how to tell the > user what is that file, and make him understand he tell the app to > use a file that doesn't exist ? >>> try: ... open("no such file.txt", "r") ... except IOError, e: ... pass ... >>> e.filename 'no such file.txt' > And this is not enough for developer : where that error happened ? > what class ? what method ? All these things are displayed by the default traceback mechanism. -- Steven D'Aprano From shurui91 at gmail.com Sun Feb 14 16:44:56 2010 From: shurui91 at gmail.com (Shurui Liu (Aaron Liu)) Date: Sun, 14 Feb 2010 10:44:56 -0500 Subject: [Tutor] command error help In-Reply-To: <2b9003cf1002140744r70a77d0cic9e70427da626c06@mail.gmail.com> References: <2b9003cf1002140734l2dba2af5j29cb7c57e40c9404@mail.gmail.com> <2b9003cf1002140744r70a77d0cic9e70427da626c06@mail.gmail.com> Message-ID: <2b9003cf1002140744j40548ae3v2c6cd1ccc5192985@mail.gmail.com> SyntaxError: EOL while scanning single-quoted string. 2010/2/14 Shurui Liu (Aaron Liu) > Here is a program I need to run in putty.exe, but there is an error in it. > I cannot find out. When I ran this program, it mentions that the error is in > red line.It shows that "SyntaxError: EOL while scanning single-quoted > string." Would you please help me? Thank you! > > > # Useless Trivia > > # > # Gets personal information from the user and then > # prints true, but useless information about him or her > > name = raw_input("Hi. What's your name? ") > > age = raw_input("And how old are you? ") > > > age = int(age) > > weight = raw_input("Okay, last question. How many pounds do you weigh? ") > weight = int(weight) > > print "\nIf poet ee cummings were to email you, he'd address you as", name.lower() > > > ee_mad = name.upper() > print "But if ee were mad, he'd call you", ee_mad > > dog_years = age / 7 > print "\nDid you know that you're just", dog_years, "in dog years?" > > > > seconds = age * 365 * 24 * 60 * 60 > print "But you're also over", seconds, "seconds old." > > called = name * 5 > print "\nIf a small child were trying to get your attention, " \ > > > "your name would become:" > print called > > moon_weight = weight / 6.0 > print "\nDid you know that on the moon you would weigh only", moon_weight, "pounds?" > > sun_weight = weight * 27.1 > > print "But on the sun, you'd weigh", sun_weight, "(but, ah... not for long)." > > raw_input("\n\nPress the enter key to exit.") > > > > -- > Shurui Liu (Aaron Liu) > Computer Science & Engineering Technology > University of Toledo > > > > -- > Shurui Liu (Aaron Liu) > Computer Science & Engineering Technology > University of Toledo > -- Shurui Liu (Aaron Liu) Computer Science & Engineering Technology University of Toledo -------------- next part -------------- An HTML attachment was scrubbed... URL: From shurui91 at gmail.com Sun Feb 14 16:34:29 2010 From: shurui91 at gmail.com (Shurui Liu (Aaron Liu)) Date: Sun, 14 Feb 2010 10:34:29 -0500 Subject: [Tutor] command error help Message-ID: <2b9003cf1002140734l2dba2af5j29cb7c57e40c9404@mail.gmail.com> Here is a program I need to run in putty.exe, but there is an error in it. I cannot find out. When I ran this program, it mentions that the error is in red line. Would you please help me? Thank you! # Useless Trivia # # Gets personal information from the user and then # prints true, but useless information about him or her name = raw_input("Hi. What's your name? ") age = raw_input("And how old are you? ") age = int(age) weight = raw_input("Okay, last question. How many pounds do you weigh? ") weight = int(weight) print "\nIf poet ee cummings were to email you, he'd address you as", name.lower() ee_mad = name.upper() print "But if ee were mad, he'd call you", ee_mad dog_years = age / 7 print "\nDid you know that you're just", dog_years, "in dog years?" seconds = age * 365 * 24 * 60 * 60 print "But you're also over", seconds, "seconds old." called = name * 5 print "\nIf a small child were trying to get your attention, " \ "your name would become:" print called moon_weight = weight / 6.0 print "\nDid you know that on the moon you would weigh only", moon_weight, "pounds?" sun_weight = weight * 27.1 print "But on the sun, you'd weigh", sun_weight, "(but, ah... not for long)." raw_input("\n\nPress the enter key to exit.") -- Shurui Liu (Aaron Liu) Computer Science & Engineering Technology University of Toledo -------------- next part -------------- An HTML attachment was scrubbed... URL: From alan.gauld at btinternet.com Sun Feb 14 17:02:19 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Sun, 14 Feb 2010 16:02:19 -0000 Subject: [Tutor] command error help References: <2b9003cf1002140734l2dba2af5j29cb7c57e40c9404@mail.gmail.com><2b9003cf1002140744r70a77d0cic9e70427da626c06@mail.gmail.com> <2b9003cf1002140744j40548ae3v2c6cd1ccc5192985@mail.gmail.com> Message-ID: "Shurui Liu (Aaron Liu)" wrote > SyntaxError: EOL while scanning single-quoted string. Yes, that sounds about right. But it doesn't add much. Can you print the entifre error message not just that single line? Or.... >> Here is a program I need to run in putty.exe, but there is an error in >> it. >> I cannot find out. When I ran this program, it mentions that the error >> is in >> red line. How are you running the code in putty. I don't get any red lines in my terminal... It suggests you might be using some other tool or IDE perhaps? Since I can't see any single quoted strings in your code we can't begin to guess what line the error pertains to. It might for example be one of the apostraphes thats causing the error? >> name = raw_input("Hi. What's your name? ") >> age = raw_input("And how old are you? ") >> age = int(age) >> >> weight = raw_input("Okay, last question. How many pounds do you weigh? >> ") >> weight = int(weight) >> >> print "\nIf poet ee cummings were to email you, he'd address you as", >> name.lower() >> ee_mad = name.upper() >> print "But if ee were mad, he'd call you", ee_mad >> >> dog_years = age / 7 >> print "\nDid you know that you're just", dog_years, "in dog years?" >> seconds = age * 365 * 24 * 60 * 60 >> print "But you're also over", seconds, "seconds old." >> >> called = name * 5 >> print "\nIf a small child were trying to get your attention, " \ >> >> "your name would become:" >> print called >> >> moon_weight = weight / 6.0 >> print "\nDid you know that on the moon you would weigh only", >> moon_weight, "pounds?" >> >> sun_weight = weight * 27.1 >> print "But on the sun, you'd weigh", sun_weight, "(but, ah... not for >> long)." >> >> raw_input("\n\nPress the enter key to exit.") -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From alan.gauld at btinternet.com Sun Feb 14 17:17:23 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Sun, 14 Feb 2010 16:17:23 -0000 Subject: [Tutor] Getting caller name without the help of"sys._getframe(1).f_code.co_name" ? References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> Message-ID: "patrice laporte" wrote > Maybe the fact I'm ? pure C coder for a longtime prevent me from thinking > in > Python, ... > And now, something different : what I want to do, and why. Based on that last line I think your brain is well on the way to thinking like a Python programmer! :-) Others have addressed your main issues. Alan G From grigor.kolev at gmail.com Sun Feb 14 20:10:40 2010 From: grigor.kolev at gmail.com (Grigor Kolev) Date: Sun, 14 Feb 2010 21:10:40 +0200 Subject: [Tutor] try MySQLdb Error Message-ID: <1266174640.22465.6.camel@dedal-laptop> Hi. I want to catch MySQL error. This is my code. -------------- next part -------------- A non-text attachment was scrubbed... Name: mail_list.py Type: text/x-python Size: 7776 bytes Desc: not available URL: From sierra_mtnview at sbcglobal.net Sun Feb 14 23:19:35 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Sun, 14 Feb 2010 14:19:35 -0800 Subject: [Tutor] A Stuborn Tab Problem in IDLE Message-ID: <4B7876F7.10806@sbcglobal.net> When I use F5 to execute a py program in IDLE, Win7, I get a tab error on an indented else. I've selected all and untabifed with 4 spaces several times, and get the same problem. I've tried re-typing the line with zero results. What next? I had been modifying the program repeatedly over several hours, and executing it without any trouble like this. -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From steve at pearwood.info Sun Feb 14 23:51:00 2010 From: steve at pearwood.info (Steven D'Aprano) Date: Mon, 15 Feb 2010 09:51:00 +1100 Subject: [Tutor] A Stuborn Tab Problem in IDLE In-Reply-To: <4B7876F7.10806@sbcglobal.net> References: <4B7876F7.10806@sbcglobal.net> Message-ID: <201002150951.01221.steve@pearwood.info> On Mon, 15 Feb 2010 09:19:35 am Wayne Watson wrote: > When I use F5 to execute a py program in IDLE, Win7, I get a tab > error on an indented else. I've selected all and untabifed with 4 > spaces several times, and get the same problem. I've tried re-typing > the line with zero results. What next? I had been modifying the > program repeatedly over several hours, and executing it without any > trouble like this. Can you copy and paste the exact error message displayed? -- Steven D'Aprano From steve at pearwood.info Mon Feb 15 00:34:00 2010 From: steve at pearwood.info (Steven D'Aprano) Date: Mon, 15 Feb 2010 10:34:00 +1100 Subject: [Tutor] operators >> and & In-Reply-To: References: <1266087514.23188.6.camel@opteron.dwabbott.com> <201002141221.49429.steve@pearwood.info> Message-ID: <201002151034.00384.steve@pearwood.info> On Sun, 14 Feb 2010 08:16:18 pm Alan Gauld wrote: > >> But glitches can occur from time to time... > > > > If Python had a glitch of the magnitude of right-shifting non-zero > > bits into a number, that would be not just a bug but a HUGE bug. > > Bit shifting is machine specific. Pardon me, but that's incorrect. Python is not assembly, or C, and the behaviour of bit shifting in Python is NOT machine specific. Python doesn't merely expose the native bit shift operations on native ints, it is a high-level object-oriented method with carefully defined semantics. http://docs.python.org/library/stdtypes.html#bit-string-operations-on-integer-types In Python, a left shift of n MUST return the equivalent of multiplication by 2**n, and a right shift MUST return the equivalent of integer division by 2**n. Any other result is a SERIOUS bug in Python of the same magnitude (and the same likelihood) as 10/2 returning 18. So while I bow to your knowledge of bit operations in assembler on obscure four bit processors, Python does not do that. (I'm not even sure if Python runs on any four bit CPUs!) Python is a high-level language, not an assembler, and the behaviour of the bit operators >> and << is guaranteed to be the same no matter what CPU you are using. (The only low-level ops that Python exposes are floating point ops: Python mostly does whatever the C library on your platform does.) > > It is certainly good practice if you are dealing with numbers which > > might be more than 24 bits to start with: > > Its more than good practice there, its essential. Hardly. There are other ways of truncating a number to 8 bits, e.g. by using n % 256. If you're dealing with signed numbers, using & 255 will throw away the sign bit, which may be undesirable. And of course, it isn't desirable (let alone essential) to truncate the number if you don't need an 8 bit number in the first place! [and discussing the case where you know your input is already 8 bits] > In the case in point the & 255 keeps the coding style consistent > and provides an extra measure of protection against unexpected > oddities so I would keep it in there. So you add unnecessary operations to be consistent? That's terrible practice. So if you have an operation like this: n = 12*i**3 + 7 and later on, you then want n = i+1, do you write: n = 1*i**1 + 1 instead to be "consistent"? I would hope not! > > cycles and needlessly complicating the code. The right way to guard > > against "this will never happen" scenarios is with assert: > > > > assert n.bit_length() <= 32 # or "assert 0 <= n < 2**32" > > I would accept the second condition but the mask is much faster. Premature (micro) optimizations is the root of all evil. An assert that can be turned off and not executed is infinitely faster than a bit shift which is always executed whether you want it or not. And either way, the 20 seconds I lose trying to interpret the bit ops when I read the code is far more important than the 0.000001 seconds I lose executing the assert :) > bit_length doesn't seem to work on any of my Pythons (2.5,2.6 and > 3.1) It won't work in 2.5 or 2.6. You're probably trying this: 123.bit_length() and getting a syntax error. That's because the Python parser sees the . and interprets it as a float, and 123.bit_length is not a valid decimal float. You need to either group the int, or refer to it by name: (123).bit_length() n = 123 n.bit_length() -- Steven D'Aprano From sierra_mtnview at sbcglobal.net Mon Feb 15 01:58:56 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Sun, 14 Feb 2010 16:58:56 -0800 Subject: [Tutor] A Stuborn Tab Problem in IDLE In-Reply-To: <201002150951.01221.steve@pearwood.info> References: <4B7876F7.10806@sbcglobal.net> <201002150951.01221.steve@pearwood.info> Message-ID: <4B789C50.8070307@sbcglobal.net> I'm not sure it's postable or attachable for this mail list. I'll give it a try. Attachments do work with other lists. On 2/14/2010 2:51 PM, Steven D'Aprano wrote: > On Mon, 15 Feb 2010 09:19:35 am Wayne Watson wrote: > >> When I use F5 to execute a py program in IDLE, Win7, I get a tab >> error on an indented else. I've selected all and untabifed with 4 >> spaces several times, and get the same problem. I've tried re-typing >> the line with zero results. What next? I had been modifying the >> program repeatedly over several hours, and executing it without any >> trouble like this. >> > Can you copy and paste the exact error message displayed? > > > > -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From alan.gauld at btinternet.com Mon Feb 15 02:02:59 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Mon, 15 Feb 2010 01:02:59 -0000 Subject: [Tutor] operators >> and & References: <1266087514.23188.6.camel@opteron.dwabbott.com><201002141221.49429.steve@pearwood.info> <201002151034.00384.steve@pearwood.info> Message-ID: "Steven D'Aprano" wrote > Pardon me, but that's incorrect. Python is not assembly, or C, and the > behaviour of bit shifting in Python is NOT machine specific. > > http://docs.python.org/library/stdtypes.html#bit-string-operations-on-integer-types > > In Python, a left shift of n MUST return the equivalent of > multiplication by 2**n, and a right shift MUST return the equivalent of > integer division by 2**n. Any other result is a SERIOUS bug in Python So it seems, I apologise, I had assumed that for bit shifting Python did indeed just pass it down to the C compiler which in turn passes it to the CPU. As someone who works a lot at the CPU level that's slightly dissappointing since it makes bit shifting predictable but unreliable from my perspective - I can't guarantee the effect on the CPU... But since it's never actually caused me a problem I won't lose sleep over it. > So while I bow to your knowledge of bit operations in assembler on > obscure four bit processors, I haven't used 4 bit CPUs since working on the millenium bug ~10 years ago but the same applies in higher order processors too. I only used a 4 bit CPU since you gave a 4 bit example. But given the above it's irrelevant, the language defines the behaviour and I was wrong about that. > Python does not do that. (I'm not even > sure if Python runs on any four bit CPUs!) Probably not but it does run on some 8 bit ones. >> > It is certainly good practice if you are dealing with numbers which >> > might be more than 24 bits to start with: >> >> Its more than good practice there, its essential. > > Hardly. There are other ways of truncating a number to 8 bits I meant the truncating was needed not the & mechanism. > [and discussing the case where you know your input is already 8 bits] >> In the case in point the & 255 keeps the coding style consistent >> and provides an extra measure of protection against unexpected >> oddities so I would keep it in there. > > So you add unnecessary operations to be consistent? That's terrible > practice. No but I don't mix two styles of guard. If I need a guard and I'm already using masks then I'll use a mask, I certainly wouldn't mix asserts and masks for similar functions. If I'm sure I don't need the guard then I definitely wouldn't add one just for consistency of style. > So if you have an operation like this: > > n = 12*i**3 + 7 > > and later on, you then want n = i+1, do you write: > > n = 1*i**1 + 1 No I'd write n = i+1 rather than n = lambda x: x+1(i) or even (if Python had such an incr function) n = incr(i) since the arithmetic version is more consistent that the function call or the lambda. >> > cycles and needlessly complicating the code. The right way to guard >> > against "this will never happen" scenarios is with assert: >> > >> > assert n.bit_length() <= 32 # or "assert 0 <= n < 2**32" >> >> I would accept the second condition but the mask is much faster. > > Premature (micro) optimizations is the root of all evil. An assert that > can be turned off and not executed is infinitely faster than a bit > shift which is always executed whether you want it or not. But I did want it :-) > And either way, the 20 seconds I lose trying to interpret the bit ops > when I read the code is far more important than the 0.000001 seconds I > lose executing the assert :) Ah, but to me bit ops are normal code so I don't lose time reading them. In fact I'd take longer to figure out the assert. Readability is all about idioms and if you do a lot of bit tweaking masking is the normal idiom. (The only difference is that I would have used hex rather than decimal numbers for the masks - because I read bit patterns in hex faster than in decimal) >> bit_length doesn't seem to work on any of my Pythons (2.5,2.6 and >> 3.1) > > It won't work in 2.5 or 2.6. You're probably trying this: > > 123.bit_length() Indeed, I tried using a variable and it worked. Thanks for that I hadn't come across bit_length() before. -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ From alan.gauld at btinternet.com Mon Feb 15 02:05:16 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Mon, 15 Feb 2010 01:05:16 -0000 Subject: [Tutor] A Stuborn Tab Problem in IDLE References: <4B7876F7.10806@sbcglobal.net> Message-ID: "Wayne Watson" wrote > When I use F5 to execute a py program in IDLE, Win7, I get a tab error > on an indented else. What happens if you execute from a command line? Do you get the same error? If so look at the lines before. If not try closing and restarting IDLE HTH, Alan G From sierra_mtnview at sbcglobal.net Mon Feb 15 03:14:35 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Sun, 14 Feb 2010 18:14:35 -0800 Subject: [Tutor] A Stuborn Tab Problem in IDLE In-Reply-To: References: <4B7876F7.10806@sbcglobal.net> Message-ID: <4B78AE0B.5090200@sbcglobal.net> I rebooted, and no change. I saved it under a new name, and no change. I tried to activate it as a file, and it put up a screen and down that I had no chance to read it. Since I have been on W7 for a month, have no clue as how to run it from a command line. I'll check with help, and report back. Maybe stuffing it in a txt file with NotePad might reveal something. On 2/14/2010 5:05 PM, Alan Gauld wrote: > > "Wayne Watson" wrote >> When I use F5 to execute a py program in IDLE, Win7, I get a tab >> error on an indented else. > > What happens if you execute from a command line? Do you get the same > error? > If so look at the lines before. > If not try closing and restarting IDLE > > HTH, > > Alan G > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From sierra_mtnview at sbcglobal.net Mon Feb 15 03:18:39 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Sun, 14 Feb 2010 18:18:39 -0800 Subject: [Tutor] A Stuborn Tab Problem in IDLE In-Reply-To: References: <4B7876F7.10806@sbcglobal.net> Message-ID: <4B78AEFF.9090202@sbcglobal.net> Well, command line was easy to get to. It's on the menu for python, but it gives me >>>. How do I get to the folder with the py file? Can I switch to a c:\ type operation? Back to exploring. On 2/14/2010 5:05 PM, Alan Gauld wrote: > > "Wayne Watson" wrote >> When I use F5 to execute a py program in IDLE, Win7, I get a tab >> error on an indented else. > > What happens if you execute from a command line? Do you get the same > error? > If so look at the lines before. > If not try closing and restarting IDLE > > HTH, > > Alan G > > _______________________________________________ > Tutor maillist - Tutor at python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From sierra_mtnview at sbcglobal.net Mon Feb 15 03:37:35 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Sun, 14 Feb 2010 18:37:35 -0800 Subject: [Tutor] A Stuborn Tab Problem in IDLE In-Reply-To: <4B78AEFF.9090202@sbcglobal.net> References: <4B7876F7.10806@sbcglobal.net> <4B78AEFF.9090202@sbcglobal.net> Message-ID: <4B78B36F.1030004@sbcglobal.net> I got to the dos command line facility and got to the file. I executed the program, and it failed with a syntax error. I can't copy it out of the window to paste here, but here's the code surrounding the problem: (arrow ==> points at the problem. The console code shows [ missing. I SEE the syntax error. It's two lines above the line with the arrow. The code now works. Thanks very much. Console wins again! (I suspect you are not into matplotlib, but the plot requires a list for x and y in plot(x,y). xy[0,0] turns out to be a float64, which the syntax rejects. I put [] around it, and it works. Is there a better way? ax1.plot([xy[0,0]],[xy[0,1]],'gs') if npts == 90: # exactly 90 frames ax1.plot([xy[npts-1,0]], xy[npts-1,1]],'rs') # mark it is a last frame else: ax1.plot([xy[npts-1,0]], ==>[xy[npts-1,1]],'ys') # mark 90th frame in path last_pt = len(xy[:,0]) ax1.plot([xy[npts-1,0]],[xy[npts-1,1]],'rs') On 2/14/2010 6:18 PM, Wayne Watson wrote: > Well, command line was easy to get to. It's on the menu for python, > but it gives me >>>. How do I get to the folder with the py file? > Can I switch to a c:\ type operation? > > Back to exploring. > > On 2/14/2010 5:05 PM, Alan Gauld wrote: >> >> "Wayne Watson" wrote >>> When I use F5 to execute a py program in IDLE, Win7, I get a tab >>> error on an indented else. >> >> What happens if you execute from a command line? Do you get the same >> error? >> If so look at the lines before. >> If not try closing and restarting IDLE >> >> HTH, >> >> Alan G >> >> _______________________________________________ >> Tutor maillist - Tutor at python.org >> To unsubscribe or change subscription options: >> http://mail.python.org/mailman/listinfo/tutor >> > -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From davea at ieee.org Mon Feb 15 04:01:19 2010 From: davea at ieee.org (Dave Angel) Date: Sun, 14 Feb 2010 22:01:19 -0500 Subject: [Tutor] A Stuborn Tab Problem in IDLE In-Reply-To: <4B78B36F.1030004@sbcglobal.net> References: <4B7876F7.10806@sbcglobal.net> <4B78AEFF.9090202@sbcglobal.net> <4B78B36F.1030004@sbcglobal.net> Message-ID: <4B78B8FF.4030005@ieee.org> Wayne Watson wrote: >

I got to > the dos command line facility and got to the file. I executed the > program, and it failed with a syntax error. I can't copy it out of the > window to paste here, but here's the code surrounding the problem: > (arrow ==> points at the problem. > The console code shows [ missing. I SEE the syntax error. It's two > lines above the line with the arrow. The code now works. Thanks very > much. Console wins again! > > (I suspect you are not into matplotlib, but the plot requires a list > for x and y in plot(x,y). xy[0,0] turns out to be a float64, which the > syntax rejects. I put [] around it, and it works. Is there a better way? > > ax1.plot([xy[0,0]],[xy[0,1]],'gs') > if npts == 90: # exactly 90 frames > ax1.plot([xy[npts-1,0]], xy[npts-1,1]],'rs') # mark it is > a last frame > else: > ax1.plot([xy[npts-1,0]], ==>[xy[npts-1,1]],'ys') # mark > 90th frame in path > last_pt = len(xy[:,0]) > ax1.plot([xy[npts-1,0]],[xy[npts-1,1]],'rs') > > On 2/14/2010 6:18 PM, Wayne Watson wrote: >> Well, command line was easy to get to. It's on the menu for python, >> but it gives me >>>. How do I get to the folder with the py file? >> Can I switch to a c:\ type operation? >> >> Back to exploring. >> >> On 2/14/2010 5:05 PM, Alan Gauld wrote: >>> >>> "Wayne Watson" wrote >>>> When I use F5 to execute a py program in IDLE, Win7, I get a tab >>>> error on an indented else. >>> >>> What happens if you execute from a command line? Do you get the same >>> error? >>> If so look at the lines before. >>> If not try closing and restarting IDLE >>> >>> HTH, >>> >>> Alan G >>> Once you've discovered the DOS box, you should also discover QuickEdit mode. In the DOS box, right click on the title bar, and choose "Properties". First tab is Options. Enable Quick-Edit mode, and press OK. Now, you can drag a rectangle on the DOS box, and use right click to paste it to the clipboard. Practice a bit and you'll find it easy. An essential tool. DaveA From sierra_mtnview at sbcglobal.net Mon Feb 15 06:47:04 2010 From: sierra_mtnview at sbcglobal.net (Wayne Watson) Date: Sun, 14 Feb 2010 21:47:04 -0800 Subject: [Tutor] A Stuborn Tab Problem in IDLE In-Reply-To: <4B78B8FF.4030005@ieee.org> References: <4B7876F7.10806@sbcglobal.net> <4B78AEFF.9090202@sbcglobal.net> <4B78B36F.1030004@sbcglobal.net> <4B78B8FF.4030005@ieee.org> Message-ID: <4B78DFD8.3060802@sbcglobal.net> Thanks for the reminder on that. I haven't need the DOS box for 8 months. Just off on other non-programming efforts for the most part. Things have picked up of late. I was beginning to think for awhile that Win7 might have dropped it. I don't see any changes to it. On 2/14/2010 7:01 PM, Dave Angel wrote: > Wayne Watson wrote: >>

I got to >> the dos command line facility and got to the file. I executed the >> program, and it failed with a syntax error. I can't copy it out of >> the window to paste here, >>>> "Wayne Watson" wrote >>>>> When I use F5 to execute a py program in IDLE, Win7, I get a tab >>>>> error on an indented else. >>>> >>>> What happens if you execute from a command line? Do you get the >>>> same error? >>>> If so look at the lines before. >>>> If not try closing and restarting IDLE >>>> >>>> HTH, >>>> >>>> Alan G >>>> > Once you've discovered the DOS box, you should also discover QuickEdit > mode. In the DOS box, right click on the title bar, and choose > "Properties". First tab is Options. Enable Quick-Edit mode, and > press OK. Now, you can drag a rectangle on the DOS box, and use right > click to paste it to the clipboard. Practice a bit and you'll find it > easy. An essential tool. > > DaveA > > -- "Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW From stefan_ml at behnel.de Mon Feb 15 09:25:41 2010 From: stefan_ml at behnel.de (Stefan Behnel) Date: Mon, 15 Feb 2010 09:25:41 +0100 Subject: [Tutor] Editing html using python In-Reply-To: References: Message-ID: Luke Paireepinart, 14.02.2010 13:12: > Also I think beautifulsoup is part of the Python standardlib now, isn't it? No, it's not. Stefan From alan.gauld at btinternet.com Mon Feb 15 09:31:07 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Mon, 15 Feb 2010 08:31:07 -0000 Subject: [Tutor] A Stuborn Tab Problem in IDLE References: <4B7876F7.10806@sbcglobal.net> <4B78AEFF.9090202@sbcglobal.net><4B78B36F.1030004@sbcglobal.net> <4B78B8FF.4030005@ieee.org> <4B78DFD8.3060802@sbcglobal.net> Message-ID: "Wayne Watson" wrote > Thanks for the reminder on that. I haven't need the DOS box for 8 > months. Just off on other non-programming efforts for the most part. > Things have picked up of late. I was beginning to think for awhile that > Win7 might have dropped it. I don't see any changes to it. Its worth running HELP on CMD and reading through it. MS usually add a few extra tricks with each new OS. And if nothing else it will remind you of the settings and registry tweaks you need to get the most out of the DOS box. The default settings are very limited. Alan G. From alan.gauld at btinternet.com Mon Feb 15 10:00:21 2010 From: alan.gauld at btinternet.com (Alan Gauld) Date: Mon, 15 Feb 2010 09:00:21 -0000 Subject: [Tutor] Editing html using python References: Message-ID: "Luke Paireepinart" wrote > with BeautifulSoup were. Also I think beautifulsoup is part of the > Python > standardlib now, isn't it? Why do you think it is not maintained? I think you may be getting confused with element tree which is part of the standard lib? BS is still an add-on. Alan G. From zepangolin at gmail.com Mon Feb 15 12:07:51 2010 From: zepangolin at gmail.com (patrice laporte) Date: Mon, 15 Feb 2010 12:07:51 +0100 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> Message-ID: <954757881002150307reeeddb7lb95ab0f09a0d69f9@mail.gmail.com> 2010/2/14 Luke Paireepinart > I see why you would want the error messages but why is the default error > message not enough, that is why I am curious, and typically introspection on > objects is not necessary (for example, people often want to convert a string > into a variable name to store a value (say they have the string "foobar1" > and they want to store the value "f" in the variable "foobar1", how do they > change foobar1 to reference a string? well you can just use exec but the > core issue is that there's really no reason to do it in the first place, > they can just use a dictionary and store dict['foobar1'] = 'f' and it is > functionally equivalent (without the danger in the code)). I get the > feeling that your issue is the same sort of thing, where an easier solution > exists but for whatever reason you don't see it. I don't know if this is > true or not. Here's my take on this: > > >>> class x(object): > def __init__(self, fname): > self.temp = open(fname).read() > > > >>> a = x('foobar') > > Traceback (most recent call last): > File "", line 1, in # this is the > module it's in > a = x('foobar') # > this is the line where I tried to initialize it > File "", line 3, in __init__ # which called > this function, which is the one that has the error > self.temp = open(fname).read() #and the error > occurred while trying to perform this operation > IOError: [Errno 2] No such file or directory: 'foobar' #and the error was > that the file 'foobar' could not be found. > > Hi and thank to everybody... First of all, I consider my first question is now answered : I wanted to get rid of that sys._getframe call, I got an explanation (thanks to Kent). The rest of the discussion is not about Python, it's more about the way of thinking how to help the user having ? good feeling with your app. I try to clarify my need and share you my anxiety. Of course, a lot of thing are available with Python, from a coder point of view. But what I want to do is to think about the user, and give him a way to understand that what he did was wrong. Traceback give me all I need, but my opinion is that it's not acceptable to give it back to the user without a minimum of "d?corating". I didn't yet look at the logging module, and maybe it can help me to make that d?corating. And the user must be a priority (it's still my conviction here) My own experience is that there is too much coder that forget the app they work on is aim to be used by "real human", not by C/C++/Python/put what ever you want here/ guru : if your app popups to the user a message that is just what the traceback gave, it's not a good thing : How can it be reasonable to imagine the user will read that kinda message ? : *Traceback (most recent call last): File "", line 1, in a = x('foobar') File "", line 3, in __init__ self.temp = open(fname).read() IOError: [Errno 2] No such file or directory: 'foobar' * Of course the origin of his problem is in the message : "*No such file or directory: 'foobar'*", but a customer will never read that @?^$#? uggly message, there is too much extraterrestrial words in it. Traceback doesn' give more thant that, it doesn't say, as an example : we (the name of app) was trying to open the file "foobar" in order to do something with it (put here what it was supposed to do with the file) : app failed to open it because "foobar" doen't exist. According to me, traceback is what we need during "coding" phases, but it's not something to give to the user. This problem has to be solved by thinking the app in the way I'm trying to explain (but not only in that way) : think about the user. This is not something I expect Python to do for me, I'm just looking for everything Python can provide me to make me think about the user. I'm new to Python, and I make a lot of exploration to understand and answer myself to my question. Python library is huge, and I don't have as enough time as I wanted to deal with it. But I'm conviced the solutions are here, I don't try to re-invent the wheel... Thant to you all. -------------- next part -------------- An HTML attachment was scrubbed... URL: From amit.pureenergy at gmail.com Mon Feb 15 13:28:06 2010 From: amit.pureenergy at gmail.com (Amit Sethi) Date: Mon, 15 Feb 2010 17:58:06 +0530 Subject: [Tutor] Editing html using python In-Reply-To: References: Message-ID: Well ya I was kind of hoping to know about more tools and recommendations on how to edit broken html . Their were tags that I wanted to replace using beautifulSoup however i saw that the replacewith function was not available for many of the tags I wanted to replace . Also BeautifulSoup does not have unicode support . So in a sense I did want recommendation perhaps I should have put my question in a better manner . -------------- next part -------------- An HTML attachment was scrubbed... URL: From peterjohnanderson at gmail.com Mon Feb 15 13:34:11 2010 From: peterjohnanderson at gmail.com (pja) Date: Mon, 15 Feb 2010 23:34:11 +1100 Subject: [Tutor] Problem with "input" in Python 3 Message-ID: <4B793F43.3070304@gmail.com> Hi! I am trying to teach myself how to program in Python using Zelle's "Python Programming: An Introduction to Computer Science" (a very good text). At the same time I have decided to start with Python 3 (3.1.1). That means that I have to convert Zelle's example code to Python 3 (which generally I cope with). I'm hoping that somebody can help with what's probably a very simple problem. There is a quadratic equation example involving multiple user inputs from the one "input" statement. The code works fine with Python 2.5 but when I convert it to Python 3 I get error messages. The code looks like: 05 import math 06 07 def main(): 08 print("This program finds the real solutions to a quadratic\n") 09 10 a, b, c = input("Please enter the coefficients (a, b, c): ") 11 12 ''' 13 a = int(input("Please enter the first coefficient: ")) 14 b = int(input("Please enter the second coefficient: ")) 15 c = int(input("Please enter the third coefficient: ")) 16 ''' 17 18 discrim = b * b - 4 * a * c 19 ... 25 main() Lines 08 to 12 are my Python 3 working solution but line 06 does not work in Python 3. When it runs it produces: Please enter the coefficients (a, b, c): 1,2,3 Traceback (most recent call last): File "C:\Program Files\Wing IDE 101 3.2\src\debug\tserver\_sandbox.py", line 25, in File "C:\Program Files\Wing IDE 101 3.2\src\debug\tserver\_sandbox.py", line 10, in main builtins.ValueError: too many values to unpack >>> Clearly the problem lies in the input statement. If I comment out line 10 and remove the comments at lines 12 and 16 then the program runs perfectly. However, I feel this is a clumsy solution. Could somebody please guide me on the correct use of "input" for multiple values. Regards, Peter -- *Peter Anderson* There is nothing more difficult to take in hand, more perilous to conduct, or more uncertain in its success, than to take the lead in the introduction of a new order of things?Niccolo Machiavelli, /The Prince/, ch. 6 From peter.anderson at internode.on.net Mon Feb 15 13:09:23 2010 From: peter.anderson at internode.on.net (Peter Anderson) Date: Mon, 15 Feb 2010 23:09:23 +1100 Subject: [Tutor] Problem with "input" in Python 3 Message-ID: <4B793973.2000102@internode.on.net> Hi! I am trying to teach myself how to program in Python using Zelle's "Python Programming: An Introduction to Computer Science" (a very good text). At the same time I have decided to start with Python 3 (3.1.1). That means that I have to convert Zelle's example code to Python 3 (which generally I cope with). I'm hoping that somebody can help with what's probably a very simple problem. There is a quadratic equation example involving multiple user inputs from the one "input" statement. The code works fine with Python 2.5 but when I convert it to Python 3 I get error messages. The code looks like: 05 import math 06 07 def main(): 08 print("This program finds the real solutions to a quadratic\n") 09 10 a, b, c = input("Please enter the coefficients (a, b, c): ") 11 12 ''' 13 a = int(input("Please enter the first coefficient: ")) 14 b = int(input("Please enter the second coefficient: ")) 15 c = int(input("Please enter the third coefficient: ")) 16 ''' 17 18 discrim = b * b - 4 * a * c 19 ... 25 main() Lines 08 to 12 are my Python 3 working solution but line 06 does not work in Python 3. When it runs it produces: Please enter the coefficients (a, b, c): 1,2,3 Traceback (most recent call last): File "C:\Program Files\Wing IDE 101 3.2\src\debug\tserver\_sandbox.py", line 25, in File "C:\Program Files\Wing IDE 101 3.2\src\debug\tserver\_sandbox.py", line 10, in main builtins.ValueError: too many values to unpack >>> Clearly the problem lies in the input statement. If I comment out line 10 and remove the comments at lines 12 and 16 then the program runs perfectly. However, I feel this is a clumsy solution. Could somebody please guide me on the correct use of "input" for multiple values. Regards, Peter -- *Peter Anderson* There is nothing more difficult to take in hand, more perilous to conduct, or more uncertain in its success, than to take the lead in the introduction of a new order of things?Niccolo Machiavelli, /The Prince/, ch. 6 From cwitts at compuscan.co.za Mon Feb 15 13:56:40 2010 From: cwitts at compuscan.co.za (Christian Witts) Date: Mon, 15 Feb 2010 14:56:40 +0200 Subject: [Tutor] Problem with "input" in Python 3 In-Reply-To: <4B793F43.3070304@gmail.com> References: <4B793F43.3070304@gmail.com> Message-ID: <4B794488.8030804@compuscan.co.za> pja wrote: > Hi! > > I am trying to teach myself how to program in Python using Zelle's > "Python Programming: An Introduction to Computer Science" (a very good > text). At the same time I have decided to start with Python 3 (3.1.1). > That means that I have to convert Zelle's example code to Python 3 > (which generally I cope with). > > I'm hoping that somebody can help with what's probably a very simple > problem. There is a quadratic equation example involving multiple user > inputs from the one "input" statement. The code works fine with Python > 2.5 but when I convert it to Python 3 I get error messages. The code > looks like: > > 05 import math > 06 > 07 def main(): > 08 print("This program finds the real solutions to a quadratic\n") > 09 > 10 a, b, c = input("Please enter the coefficients (a, b, c): ") > 11 > 12 ''' > 13 a = int(input("Please enter the first coefficient: ")) > 14 b = int(input("Please enter the second coefficient: ")) > 15 c = int(input("Please enter the third coefficient: ")) > 16 ''' > 17 > 18 discrim = b * b - 4 * a * c > 19 ... > > 25 main() > > Lines 08 to 12 are my Python 3 working solution but line 06 does not > work in Python 3. When it runs it produces: > > Please enter the coefficients (a, b, c): 1,2,3 > Traceback (most recent call last): > File "C:\Program Files\Wing IDE 101 > 3.2\src\debug\tserver\_sandbox.py", line 25, in > File "C:\Program Files\Wing IDE 101 > 3.2\src\debug\tserver\_sandbox.py", line 10, in main > builtins.ValueError: too many values to unpack > >>> > > Clearly the problem lies in the input statement. If I comment out line > 10 and remove the comments at lines 12 and 16 then the program runs > perfectly. However, I feel this is a clumsy solution. > > Could somebody please guide me on the correct use of "input" for > multiple values. > > Regards, > Peter You will need to split your input. no_input = True while no_input: in = input("Please enter the coefficients (a, b, c): ") try: a, b, c = map(int, in.split(',')) no_input = False except ValueError: print("Please enter your input in a comma-seperated format with no space. Only 3 numbers allowed") That will loop allowing input until the person enters 3 numbers seperated purely by commas in for input. -- Kind Regards, Christian Witts Business Intelligence C o m p u s c a n | Confidence in Credit Telephone: +27 21 888 6000 National Cell Centre: 0861 51 41 31 Fax: +27 21 413 2424 E-mail: cwitts at compuscan.co.za NOTE: This e-mail (including attachments )is subject to the disclaimer published at: http://www.compuscan.co.za/live/content.php?Item_ID=494. If you cannot access the disclaimer, request it from email.disclaimer at compuscan.co.za or 0861 514131. National Credit Regulator Credit Bureau Registration No. NCRCB6 From stefan_ml at behnel.de Mon Feb 15 13:53:52 2010 From: stefan_ml at behnel.de (Stefan Behnel) Date: Mon, 15 Feb 2010 13:53:52 +0100 Subject: [Tutor] Editing html using python In-Reply-To: References: Message-ID: Amit Sethi, 15.02.2010 13:28: > Well ya I was kind of hoping to know about more tools and recommendations on > how to edit broken html. You already found lxml, don't think you can do any better. Note that you shouldn't "edit broken html" but "fix broken HTML and then edit correct HTML". Writing out broken HTML after editing it is likely not what you want. > Their were tags that I wanted to replace using beautifulSoup > however i saw that the replacewith function was not available for many of > the tags I wanted to replace. To understand your problem better, it would be helpful if you provided more information, such as the names of the tags and a short example code snippet that showed what you were trying to do. > Also BeautifulSoup does not have unicode support. Try to learn a tool before making blatantly false claims about it. > So in a sense I did want recommendation perhaps I should have put my > question in a better manner. That's a very good idea. This will help: http://catb.org/~esr/faqs/smart-questions.html Stefan From kent37 at tds.net Mon Feb 15 13:59:32 2010 From: kent37 at tds.net (Kent Johnson) Date: Mon, 15 Feb 2010 07:59:32 -0500 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: <954757881002150307reeeddb7lb95ab0f09a0d69f9@mail.gmail.com> References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> <954757881002150307reeeddb7lb95ab0f09a0d69f9@mail.gmail.com> Message-ID: <1c2a2c591002150459l29f60f21ia00a99bae8a7d26f@mail.gmail.com> On Mon, Feb 15, 2010 at 6:07 AM, patrice laporte wrote: > My own experience is that there is too much coder that forget the app they > work on is aim to be used by "real human", not by C/C++/Python/put what ever > you want here/ guru : if your app popups to the user a message that is just > what the traceback gave, it's not a good thing : How can it be reasonable to > imagine the user will read that kinda message ? : > > Traceback (most recent call last): > ? File "", line 1, in > ??? a = x('foobar') > ? File "", line 3, in __init__ > ??? self.temp = open(fname).read() > IOError: [Errno 2] No such file or directory: 'foobar' > > Of course the origin of his problem is in the message : "No such file or > directory: 'foobar'", but a customer will never read that @?^$#? uggly > message, there is too much extraterrestrial words in it. It's easy to give the user just the actual error message, either the full IOError: [Errno 2] No such file or directory: 'foobar' or slightly friendlier: No such file or directory: 'foobar' Then log the full trackback to a file. If the user needs help, ask them to send you the log file. They never see the full traceback and you get all the information available. > Traceback doesn' give more thant that, it doesn't say, as an example : we > (the name of app) was trying to open the file "foobar" in order to do > something with it (put here what it was supposed to do with the file) : app > failed to open it because "foobar" doen't exist. In a GUI app the user will often know what was happening, because they asked to do it. Often it is more useful to give context from the point where the exception is caught because that is a higher-level location than the point of failure. When you catch the exception you can tell the user Error processing No such file or directory: 'foobar' This will make more sense than the low-level details of the error. > According to me, traceback is what we need during "coding" phases, but it's > not something to give to the user. > > This problem has to be solved by thinking the app in the way I'm trying to > explain? (but not only in that way) : think about the user. This is not > something I expect Python to do for me, I'm just looking for everything > Python can provide me to make me think about the user. This is a good goal. I'm not sure it requires wrapping the exception mechanism to achieve it. Kent From kent37 at tds.net Mon Feb 15 14:05:19 2010 From: kent37 at tds.net (Kent Johnson) Date: Mon, 15 Feb 2010 08:05:19 -0500 Subject: [Tutor] Editing html using python In-Reply-To: References: Message-ID: <1c2a2c591002150505m741d417dufb13d2e69d5effb@mail.gmail.com> On Mon, Feb 15, 2010 at 7:28 AM, Amit Sethi wrote: > Well ya I was kind of hoping to know about more tools and recommendations on > how to edit broken html . This page lists several alternatives: html5, lxml, elementtree: http://www.crummy.com/software/BeautifulSoup/3.1-problems.html > Their were tags that I wanted to replace using > beautifulSoup > however i saw that the replacewith function was not available for many of > the tags I > wanted to replace . Also BeautifulSoup does not have unicode support . ?? http://www.crummy.com/software/BeautifulSoup/documentation.html#Beautiful%20Soup%20Gives%20You%20Unicode,%20Dammit Kent From kent37 at tds.net Mon Feb 15 14:09:26 2010 From: kent37 at tds.net (Kent Johnson) Date: Mon, 15 Feb 2010 08:09:26 -0500 Subject: [Tutor] Problem with "input" in Python 3 In-Reply-To: <4B793F43.3070304@gmail.com> References: <4B793F43.3070304@gmail.com> Message-ID: <1c2a2c591002150509y29849c8cr4fe7fba2ea09fa70@mail.gmail.com> On Mon, Feb 15, 2010 at 7:34 AM, pja wrote: > 05 import math > 06 > 07 def main(): > 08 print("This program finds the real solutions to a quadratic\n") > 09 > 10 a, b, c = input("Please enter the coefficients (a, b, c): ") > 11 > 12 ''' > 13 a = int(input("Please enter the first coefficient: ")) > 14 b = int(input("Please enter the second coefficient: ")) > 15 c = int(input("Please enter the third coefficient: ")) > 16 ''' > 17 > 18 discrim = b * b - 4 * a * c > 19 ... > > 25 main() > > Lines 08 to 12 are my Python 3 working solution but line 06 does not work in > Python 3. When it runs it produces: > > Please enter the coefficients (a, b, c): 1,2,3 > Traceback (most recent call last): > File "C:\Program Files\Wing IDE 101 3.2\src\debug\tserver\_sandbox.py", line > 25, in > File "C:\Program Files\Wing IDE 101 3.2\src\debug\tserver\_sandbox.py", line > 10, in main > builtins.ValueError: too many values to unpack >>>> > > Clearly the problem lies in the input statement. If I comment out line 10 > and remove the comments at lines 12 and 16 then the program runs perfectly. > However, I feel this is a clumsy solution. > > Could somebody please guide me on the correct use of "input" for multiple > values. Python 3 input() is the same as Python 2 raw_input() - the result is a string. You could use a, b, c = ast.literal_eval(input("Please enter the coefficients (a, b, c): ")) Kent From waynejwerner at gmail.com Mon Feb 15 14:10:57 2010 From: waynejwerner at gmail.com (Wayne Werner) Date: Mon, 15 Feb 2010 07:10:57 -0600 Subject: [Tutor] Problem with "input" in Python 3 In-Reply-To: <4B793973.2000102@internode.on.net> References: <4B793973.2000102@internode.on.net> Message-ID: <333efb451002150510t66d0c650mcff40e94f2883fd8@mail.gmail.com> On Mon, Feb 15, 2010 at 6:09 AM, Peter Anderson < peter.anderson at internode.on.net> wrote: > Hi! > > I am trying to teach myself how to program in Python using Zelle's "Python > Programming: An Introduction to Computer Science" (a very good text). At the > same time I have decided to start with Python 3 (3.1.1). That means that I > have to convert Zelle's example code to Python 3 (which generally I cope > with). > > I'm hoping that somebody can help with what's probably a very simple > problem. There is a quadratic equation example involving multiple user > inputs from the one "input" statement. The code works fine with Python 2.5 > but when I convert it to Python 3 I get error messages. The code looks like: > > 05 import math > 06 > 07 def main(): > 08 print("This program finds the real solutions to a quadratic\n") > 09 > 10 a, b, c = input("Please enter the coefficients (a, b, c): ") > 11 > 12 ''' > 13 a = int(input("Please enter the first coefficient: ")) > 14 b = int(input("Please enter the second coefficient: ")) > 15 c = int(input("Please enter the third coefficient: ")) > 16 ''' > 17 > 18 discrim = b * b - 4 * a * c > 19 ... > > 25 main() > > Lines 08 to 12 are my Python 3 working solution but line 06 does not work > in Python 3. When it runs it produces: > > Please enter the coefficients (a, b, c): 1,2,3 > Traceback (most recent call last): > File "C:\Program Files\Wing IDE 101 3.2\src\debug\tserver\_sandbox.py", > line 25, in > File "C:\Program Files\Wing IDE 101 3.2\src\debug\tserver\_sandbox.py", > line 10, in main > builtins.ValueError: too many values to unpack > >>> > > Clearly the problem lies in the input statement. If I comment out line 10 > and remove the comments at lines 12 and 16 then the program runs perfectly. > However, I feel this is a clumsy solution. > > Could somebody please guide me on the correct use of "input" for multiple > values. > First off, it's much healthier to use "raw_input", and then try to convert it (float, int, whatever). Example: In [1]: x = input("Test: ") Test: print "Ha ha, this is some input" ------------------------------------------------------------ File "", line 1 print "Ha ha, this is some input" ^ SyntaxError: invalid syntax In [3]: x = raw_input("Test: ") Test: print "ha ha, this is some raw_input" In [4]: x Out[4]: 'print "ha ha, this is some raw_input"' The first one is susceptible to people inserting malicious code (at least in pre-3.0 versions). The reason your code is throwing an error is input (or raw_input) gives you one value, and you're trying to assign it to three variables. If you want to get 3 floating point values, the most concise (but maybe not so readable if you're not familiar with the syntax) is probably this: a, b, c = [float(x) for x in raw_input("Please enter (a, b, c): ").split()] Example: In [6]: a, b, c = [float(x) for x in raw_input("Please enter (a, b, c): ").split()] Please enter (a, b, c): 3.1 2.99 1 In [7]: a Out[7]: 3.1000000000000001 In [8]: b Out[8]: 2.9900000000000002 In [9]: c Out[9]: 1.0 to understand what the above code is doing: print raw_input("Please enter (a,b, c): ") print raw_input("Please enter (a,b, c): ").split() print [x for x in raw_input("Please enter (a,b, c): ").split()] print [float(x) for x in raw_input("Please enter (a,b, c): ").split()] HTH, Wayne -------------- next part -------------- An HTML attachment was scrubbed... URL: From davea at ieee.org Mon Feb 15 14:11:09 2010 From: davea at ieee.org (Dave Angel) Date: Mon, 15 Feb 2010 08:11:09 -0500 Subject: [Tutor] Getting caller name without the help of "sys._getframe(1).f_code.co_name" ? In-Reply-To: <954757881002150307reeeddb7lb95ab0f09a0d69f9@mail.gmail.com> References: <954757881002130756y77df8885o42d313f5a6477aaa@mail.gmail.com> <954757881002140333m2e839324v441aa81de06b51ac@mail.gmail.com> <954757881002150307reeeddb7lb95ab0f09a0d69f9@mail.gmail.com> Message-ID: <4B7947ED.1060000@ieee.org> patrice laporte wrote: > 2010/2/14 Luke Paireepinart > > >> I see why you would want the error messages but why is the default error >> message not enough, that is why I am curious, and typically introspection on >> objects is not necessary (for example, people often want to convert a string >> into a variable name to store a value (say they have the string "foobar1" >> and they want to store the value "f" in the variable "foobar1", how do they >> change foobar1 to reference a string? well you can just use exec but the >> core issue is that there's really no reason to do it in the first place, >> they can just use a dictionary and store dict['foobar1'] = 'f' and it is >> functionally equivalent (without the danger in the code)). I get the >> feeling that your issue is the same sort of thing, where an easier solution >> exists but for whatever reason you don't see it. I don't know if this is >> true or not. Here's my take on this: >> >> >>>>> class x(object): >>>>> >> def __init__(self, fname): >> self.temp = open(fname).read() >> >> >> >>>>> a = x('foobar') >>>>> >> Traceback (most recent call last): >> File "", line 1, in # this is the >> module it's in >> a = x('foobar') # >> this is the line where I tried to initialize it >> File "", line 3, in __init__ # which called >> this function, which is the one that has the error >> self.temp = open(fname).read() #and the error >> occurred while trying to perform this operation >> IOError: [Errno 2] No such file or directory: 'foobar' #and the error was >> that the file 'foobar' could not be found. >> >> >> > Hi and thank to everybody... > > First of all, I consider my first question is now answered : I wanted to get > rid of that sys._getframe call, I got an explanation (thanks to Kent). > > The rest of the discussion is not about Python, it's more about the way of > thinking how to help the user having ? good feeling with your app. > > I try to clarify my need and share you my anxiety. Of course, a lot of thing > are available with Python, from a coder point of view. But what I want to do > is to think about the user, and give him a way to understand that what he > did was wrong. > > Traceback give me all I need, but my opinion is that it's not acceptable to > give it back to the user without a minimum of "d?corating". I didn't yet > look at the logging module, and maybe it can help me to make that > d?corating. > > And the user must be a priority (it's still my conviction here) > > My own experience is that there is too much coder that forget the app they > work on is aim to be used by "real human", not by C/C++/Python/put what ever > you want here/ guru : if your app popups to the user a message that is just > what the traceback gave, it's not a good thing : How can it be reasonable to > imagine the user will read that kinda message ? : > > *Traceback (most recent call last): > File "", line 1, in > a = x('foobar') > File "

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