[Python-modules-team] Bug#489253: should numpy be built with atlas?

[otizonaizit at yahoo.com]

On Mon, Jul 7, 2008 at 2:12 PM, Matthias Klose <doko at cs.tu-berlin.de> wrote:
> Package: python-numpy
> Version: 1:1.1.0-2
> Severity: serious
>
> python-numpy now has an unconditional dependency on libatlas3gf-base,
> needing the "specialized" atlas libraries as a runtime
> dependency. Users still should have the option to use the standard
> blas and lapack libs instead of the untested/unmaintained atlas
> libraries in debian.

The problem is that the new (>1.0) numpy building system needs ATLAS 
at compile time to enable fast matrix-multiplication. If ATLAS is not found
at compile time, numpy.core._dotblas.so is not built and slow matrix 
multiplication is used even if the end user has ATLAS installed. In the old
numpy _dotblas.so was always compiled using refblas and the end user 
would still have had the option of using ATLAS. I'm not sure I understand 
why ATLAS is now needed at compile time, but look here:
http://scipy.org/scipy/numpy/ticket/667
and here:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=464784

I think python-numpy should stay as it is now and a bug-wishlist should be 
reported to the atlas package to encourage packaging of the new stable
 version (3.8.2). Filing a ticket on numpy trac may help, but the fate of 
ticket 667 seems to indicate that there's no will of fixing this bug upstream...

thank you, 
tiziano