Mailman 3 November 2009 - NumPy-Discussion

Backout complex changes for next release?
by Charles R Harris 07 Nov '09

07 Nov '09

There seems to be a rat's nest of problems showing up in scipy due to the recent changes in numpy complex support. The problems are of two basic sorts: 1) reserved name conflicts and 2) file conflicts. The first could be dealt with, but the second might be trickier, both c/c++ defined complex.h but the files are different. C++ has moved on, but not all platforms seem to have followed. Given the proposed schedule for the next numpy release and the developing problems, it seems to me we should back out the changes to complex support and concentrate on more pressing matters. Chuck

2 1

Comparing variable time-shifted two measurements
by Gökhan Sever 06 Nov '09

06 Nov '09

Hello, I have two aircraft based aerosol measurements. The first one is dccnConSTP (blue), and the latter is CPCConc (red) as shown in this screen capture. ( http://img513.imageshack.us/img513/7498/ccncpclag.png). My goal is to compare these two measurements. It is expected to see that they must have a positive correlation throughout the flight. However, the instrument that gives CPCConc was experiencing a sampling issue and therefore making a varying time-shifted measurements with respect to the first instrument. (From the first box it is about 20 seconds, 24 from the seconds before the dccnConSTP measurements shows up.) In other words in different altitude levels, I have varying time differences in between these two measurements in terms of their shapes. So, my goal turns to addressing this variable shifting issue before I start doing the comparisons. Is there a known automated approach to correct this mentioned varying-lag issue? If so, how? Thank you. -- Gökhan

2 4

Fwd: [Distutils] People want CPAN :-)
by John Hunter 06 Nov '09

06 Nov '09

I assume many of you follow distutils, but FYI in case you want to contribute to the discussion ---------- Forwarded message ---------- From: Alex Grönholm <alex.gronholm(a)nextday.fi> Date: 2009/11/6 Subject: Re: [Distutils] People want CPAN :-) To: distutils-sig(a)python.org Guido van Rossum kirjoitti: > > I just found this comment on my blog. People have told me this in > person too, so I believe it is real pain (even if the solution may be > elusive and the suggested solutions may not work). But I don't know > how to improve the world. Is the work on distutils-sig going to be > enough? Or do we need some other kind of work in addition? Do we need > more than PyPI? > > --Guido > > ---------- Forwarded message ---------- > From: dalloliogm <noreply-comment(a)blogger.com> > Date: Fri, Nov 6, 2009 at 8:01 AM > Subject: [Neopythonic] New comment on Python in the Scientific World. > To: gvanrossum(a)gmail.com > > > dalloliogm has left a new comment on your post "Python in the Scientific World": > > Python is suffering a lot in the scientific word, because it has not a > CPAN-like repository. > > PyPI is fine, but it is still far from the level of CPAN, CRAN, > Bioconductor, etc.. > > Scientists who use programming usually have a lot of different > interests and approaches, therefore it is really difficult to write a > package that can be useful to everyone. > Other programming language like Perl and R have repository-like > structure which enable people to download packages easily, and to > upload new ones and organize them withouth having to worry about > having to integrate them into existing packages. > > This is what is happening to biopython now: it is a monolitic package > that it is supposed to work for any bioinformatic problem; but this is > so general that to accomplish that you would need to add a lot of > dependencies, to numpy, networkx, suds, any kind of library. > However, since easy_install is not as ready yet as the counterparts in > other languages, if the biopython developers add too many > dependencies, nobody will be able to install it properly, and nobody > will use it. > I for one did not understand the problem. What does CPAN have that PyPI doesn't? It is natural for packages (distributions, in distutils terms) to have dependencies on each other. Why is this a problem? > > > Posted by dalloliogm to Neopythonic at November 6, 2009 8:01 AM > > > _______________________________________________ Distutils-SIG maillist - Distutils-SIG(a)python.org http://mail.python.org/mailman/listinfo/distutils-sig

1 0

Formatting uint64 number
by Thomas Robitaille 06 Nov '09

06 Nov '09

Hello, I have a question concerning uint64 numbers - let's say I want to format a uint64 number that is > 2**31, at the moment it's necessary to wrap the numpy number inside long before formatting In [3]: "%40i" % np.uint64(2**64-1) Out[3]: ' -1' In [4]: "%40i" % long(np.uint64(2**64-1)) Out[4]: ' 18446744073709551615' Would it be easy to modify numpy such that it automatically converts uint64 numbers to long() instead of int() when implicitly converted to python types? Thanks, Thomas

3 4

object to string for numpy 1.3.0
by Thomas Robitaille 06 Nov '09

06 Nov '09

Hello, Until recently, object to string conversion was buggy: In [1]: import numpy as np In [2]: a = np.array(['4TxismCut','nXe4f0sAs'],dtype=np.object_) In [3]: np.array(a,dtype='|S9') Out[3]: array(['4TxismCun', 'Xe4f0sAs'], dtype='|S9') (notice the strings are not quite the same) This is now fixed in svn, but is there a way to write the conversion differently such that it does work with numpy 1.3.0? (so as not to have to force users of a package to upgrade to numpy 1.4.0) Thanks, Thomas

1 0

Bits info in np.finfo
by Thomas Robitaille 06 Nov '09

06 Nov '09

Hi, Is there a reason that np.finfo does not have a bits attribute? In [6]: np.iinfo(np.int16).bits Out[6]: 16 In [7]: np.finfo(np.float32).bits --------------------------------------------------------------------------- AttributeError Traceback (most recent call last) /Users/tom/<ipython console> in <module>() AttributeError: 'finfo' object has no attribute 'bits' Should I submit a bug report? Thanks, Thomas

2 1

[ANN] For SF Bay Area residents: a discussion with Guido at the Berkeley Py4Science seminar
by Fernando Perez 06 Nov '09

06 Nov '09

Hi folks, if you reside in the San Francisco Bay Area, you may be interested in a meeting we'll be having tomorrow November 4 (2-4 pm), as part of our regular py4science meeting series. Guido van Rossum, the creator of the Python language, will visit for a session where we will first do a very rapid overview of a number of scientific projects that use Python (in a lightning talk format) and then we will have an open discussion with Guido with hopefully interesting questions going in both directions. The meeting is open to all, bring your questions! More details on this seminar series (including location) can be found here: https://cirl.berkeley.edu/view/Py4Science Cheers, f

1 1

persistent ImportError: No module named multiarray when moving cPickle files between machines
by Reckoner 05 Nov '09

05 Nov '09

Hi, % python -c 'import numpy.core.multiarray' works just fine, but when I try to load a file that I have transferred from another machine running Windows to one running Linux, I get: % python -c 'import cPickle;a=cPickle.load(open("matrices.pkl"))' Traceback (most recent call last): File "<string>", line 1, in <module> ImportError: No module named multiarray otherwise, cPickle works normally when transferring files that *do* not contain numpy arrays. I am using version 1.2 on both machines. It's not so easy for me to change versions, by the way, since this is the version that my working group has decided on to standardize on for this effort. Any help appreciated.

5 18

http://www.scipy.org/Installing_SciPy down
by Gaston Fiore 05 Nov '09

05 Nov '09

Hello, It seems that http://www.scipy.org/Installing_SciPy among other URLs with links on http://numpy.scipy.org/ is down. Does anyone know an estimate for when they'll be back up? Thanks, -Gaston

2 2

ANN: SciPy India 2009 Call for Presentations
by Jarrod Millman 05 Nov '09

05 Nov '09

Call for Presentations ====================== The SciPy India 2009 Program Committee is currently developing the conference program. We are seeking presentations from industry as well as the academic world. We look forward to hearing your recent breakthroughs using Python! Please read the full `call for papers <http://scipy.in/talks-cfp/>`_. SciPy India 2009 Conference --------------------------- The first `SciPy India Conference <http://scipy.in>`_ will be held from December 12th to 17th, 2009 at the `Technopark in Trivandrum <http://www.technopark.org/>`_, Kerala, India. The theme of the conference will be "Scientific Python in Action" with respect to application and teaching. We are pleased to have Travis Oliphant, the creator and lead developer of `numpy <http://numpy.scipy.org>`_ as the keynote speaker. Please register `here <http://scipy.in>`_. Important Dates --------------- * Friday, Nov. 20: Abstracts Due * Friday, Nov. 27: Announce accepted talks, post schedule * Saturday-Sunday, Dec. 12-13 Conference * Monday-Tuesday, Dec. 14-15 Tutorials * Wednesday-Thursday, Dec. 16-17 Sprints Organizers ---------- * Jarrod Millman, Neuroscience Institute, UC Berkeley, USA (Conference Co-Chair) * Prabhu Ramachandran, Department of Aerospace Engineering, IIT Bombay, India (Conference Co-Chair) * FOSSEE Team Sponsors -------- * National Mission On Education through ICT - Ministry of Human Resource Development, Government of India * SPACE-Kerala (India) * Kerala State IT Mission(KSITM) * SIG-FOSS Of CSI

1 0