Re: [Numpy-discussion] C or C++ package like NumPy?
Sorry : http://kogs-www.informatik.uni-hamburg.de/~koethe/vigra/ It has some publications written about the design it uses (iterators and such), really well done. Matthieu 2007/11/2, Bill Baxter [EMAIL PROTECTED]: On Nov 2, 2007 3:50 PM, Matthieu Brucher [EMAIL PROTECTED] wrote: You can look at Vigra (but I don't know if there is linear algebra, but there are views, multidimensional containers, ...). Thanks for the link. Hadn't heard of that one. --bb ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion -- French PhD student Website : http://miles.developpez.com/ Blogs : http://matt.eifelle.com and http://blog.developpez.com/?blog=92 ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] C or C++ package like NumPy?
Oh, I didn't realize you didn't give a link. I just googled reflexively. Anyway, that makes me think of the other generic image library I've heard of -- Adobe's GIL. Never really looked at it in much detail but checking now, it looks like it does support N-dim images. http://opensource.adobe.com/gil/html/gildesignguide.html#ImageSectionDG --bb On Nov 2, 2007 4:00 PM, Matthieu Brucher [EMAIL PROTECTED] wrote: Sorry : http://kogs-www.informatik.uni-hamburg.de/~koethe/vigra/ It has some publications written about the design it uses (iterators and such), really well done. Matthieu 2007/11/2, Bill Baxter [EMAIL PROTECTED]: On Nov 2, 2007 3:50 PM, Matthieu Brucher [EMAIL PROTECTED] wrote: You can look at Vigra (but I don't know if there is linear algebra, but there are views, multidimensional containers, ...). Thanks for the link. Hadn't heard of that one. --bb ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion -- French PhD student Website : http://miles.developpez.com/ Blogs : http://matt.eifelle.com and http://blog.developpez.com/?blog=92 ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] numpy FFT memory accumulation
At 10:57 PM 11/1/2007, Charles R Harris wrote: An additional complication is that I pass the numpy (or Numeric) array address to the ctypes library call so that the data is placed directly into the array from the call. I use the if/else end wrap logic to determine whether I need to do a split and copy if the new data wraps. OK. Hmm, I wonder if you would lose much by taking a straight forward radix-2 fft and teaching it to use modular indices? Probably not worth the trouble, but an fft tailored to a ring buffer might be useful for other things. The problem is, I once compiled my own FFT dll to call from Python and it was 2x slower than FFTPACK - I'm not math-smart enough to make all of the caching and numerical shortcuts. That, and Intel's optimized FFT is 3x faster than FFTPACK... I may still try to do a zoom/range FFT which does not compute all bins, and maybe only with a sine transform, which (I think) should be sufficient to determine peak real frequency and maybe use fewer cycles. Probably the easiest thing is to just copy the ring buffer out into a linear array. I do that for the buffer-wrap condition, while simply assigning a slice (no copy) to the temp array otherwise. I used Numeric functions for the ~40% speed increase, but I don't I know that numarray was slow in creating small arrays, but is Numpy really that bad compared to Numeric? I just saw the # of FFTs/sec go from 390 to 550 just by switching numpy to Numeric (Intel Core Duo). Add a timer to my previous code posts and see how your results look. For the mega-arrays a lot of the numpy developers work with it is much faster, and I now find Numeric is lacking many other niceties, like frombuffer(). Ray -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.503 / Virus Database: 269.15.18/1104 - Release Date: 11/1/2007 6:47 PM ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] C or C++ package like NumPy?
Charles R Harris wrote: On 11/1/07, Bill Baxter [EMAIL PROTECTED] wrote: Ah, ok. Thanks. That does look like a good example. I've heard of it, but never looked too closely for some reason. I guess I always thought of it as the library that pioneered expression templates but that no one actually uses. I believe it is no longer maintained. I might be wrong about that, though. Chuck It is being maintained, at least to some extent. See: [EMAIL PROTECTED] ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] vectorizing loops
A Thursday 01 November 2007, Timothy Hochberg escrigué: On Nov 1, 2007 7:14 AM, David M. Cooke [EMAIL PROTECTED] Another issue is that numexpr is still in the scipy sandbox, so only those who enable it will use it (or use it through PyTables). One problem with moving it out is that Tim reports the compile times on Windows are ridiculous (20 mins!). While this is true at the default optimization (O2), it compiles reasonably quickly at O1 and I've never been able to detect a speed difference between versions compiled with O1 versus O2. It would probably be sufficient to crank back the optimization on Windows. Yes. This has been my experience too on Windows/MSVC boxes. Maybe numexpr should become a scikit? It certainly doesn't need the rest of scipy. Call me intrepid, but I've always felt that numexpr belongs more to numpy itself than scipy. However, I agree that perhaps it should be a bit more polished (but not much; perhaps just adding some functions like, exp, log, log10... would be enough) before being integrated. At any rate, Numexpr would be a extremely useful complement to NumPy. My two cents, -- 0,0 Francesc Altet http://www.carabos.com/ V V Cárabos Coop. V. Enjoy Data - ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] vectorizing loops
A Thursday 01 November 2007, David M. Cooke escrigué: At any rate, we would be glad if you would like to integrate our patches in the main numexpr, as there is not much sense to have different implementations of numexpr (most specially when it seems that there are not much users out there). So, count on us for any question you may have in this regard. Well, I don't have much time to work on it, but if you make sure your patches on the scipy Trac apply clean, I'll have a quick look at them and apply them. Since you've had them working in production code, they should be good ;-) Well, being in production and around 1 tests (where numexpr is involved) in the pytables package seems a good guarantee to me too ;-) I've attached a clean patch to ticket #529 of SciPy site: http://scipy.org/scipy/scipy/ticket/529 However, I've committed a couple of mistakes during ticket creation, so: - in #529, I've uploaded the patch twice, so they are exactly the same - please mark #530 as invalid (duplicated) Cheers, -- 0,0 Francesc Altet http://www.carabos.com/ V V Cárabos Coop. V. Enjoy Data - ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
[Numpy-discussion] Round 2 with Leopard+Python
Hi, In the process of working through the issues with sys.path on Leopard, I have found another potential Leopard bug that is particularly nasty. In Tiger, sudo preserves environment variables: $ export FOO=/tmp $ python -c import os; print os.environ['FOO'] /tmp $ sudo python -c import os; print os.environ['FOO'] /tmp But, in Leopard, sudo does not perserve environment variables: $ export FOO=/tmp $ python -c import os; print os.environ['FOO'] /tmp $ sudo python -c import os; print os.environ['FOO'] Password: Traceback (most recent call last): File string, line 1, in module File /System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/UserDict.py, line 22, in __getitem__ raise KeyError(key) KeyError: 'FOO' This is a big problem. First, if you have set PYTHONPATH to point sys.path at the site-packages in /Library, this setting will be lost when you do: sudo python setup.py install On another package. I encountered this in building pytables, which requires numpy = 1.0.3. I had installed numpy 1.0.4, and set my PYTHONPATH to point to it. But, the pytables setup.py script failts because PYTHONPATH is lost and it only sees the older (1.0.1) builtin numpy. Second, some setup.py scripts use environment variables to determine how things are built, find other dependencies, etc. Currently, this will fail on Leopard if such packages are installed into locations that require sudo. I haven't tried it yet, but I expect that this will also hold true for other python installations. The behavior also shows up with ruby on Leopard. The solution currently is to install all packages to locations that don't require sudo to write to. I will file a bug report, but until the bug is fixed, we should explore putting a note on the numpy/scipy site - and even possibly on the python.org site to describe the problem and its workaround. Brian ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] weird numpy/pickle problem
On 11/2/07 12:00, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Date: Fri, 2 Nov 2007 12:58:33 -0400 From: Brian Blais [EMAIL PROTECTED] Subject: [Numpy-discussion] weird numpy/pickle problem To: numpy-discussion@scipy.org I boiled it down to the code below. Can anyone reproduce (or not) this error? Works for me on OS X 10.4.9, Python 2.5.0, numpy 1.0.4dev3977. -Neil -- The theory of probabilities is at bottom nothing but common sense reduced to calculus. -- Pierre Simon de Laplace ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
Re: [Numpy-discussion] weird numpy/pickle problem
On Fri, Nov 02, 2007 at 12:58:33PM -0400, Brian Blais wrote: I encountered a peculiar numpy and pickle problem. My version: Python 2.5.1 (r251:54869, Apr 18 2007, 22:08:04) Mac OS X Tiger In [2]:numpy.__version__ Out[2]:'1.0.4.dev3869' I pickle a matrix, and reload it. Some operations work ok, but others give a hardware error and a crash! I boiled it down to the code below. Can anyone reproduce (or not) this error? This ticket looks similar: http://projects.scipy.org/scipy/numpy/ticket/551 Cheers Stéfan ___ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
