[Numpy-discussion] Numpy without BLAS, LAPACK

[David M. Cooke]

On 22 Nov 2006 16:44:07 -0000
vallis.35530053 at bloglines.com wrote:

> (Reposting to numpy-discussion at scipy.org instead of the SourceForge list.)
> 
> 
> It is my understanding that Numpy has "lite" versions of BLAS and LAPACK
> that it will use if it cannot find system libraries. Is it possible to FORCE
> it to use the lite versions rather than existing system libraries?
> 
> (Where
> I come from: I'm trying to install numpy in a local directory on a Beowulf
> cluster, which has local BLAS and LAPACK that the numpy setup finds;
> however, these libraries are missing some functions, so "import numpy"
> fails at numpy.linalg. The fact is that I don't need numpy.linalg at all,
> so I'd be very happy with the lite libraries, rather than going to the
> trouble of recompiling BLAS and LAPACK or ATLAS, etc.)

Set the environment variables ATLAS, BLAS, and LAPACK to 'None'. For instance,

$ ATLAS=None BLAS=None LAPACK=None python setup.py install

Note that numpy.dot() uses BLAS if it's found, so if you compile without it,
it'll be slower. This may impact other routines not in numpy.linalg.

(It's on my list to add a faster xgemm routine when BLAS isn't used...)

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|David M. Cooke                      http://arbutus.physics.mcmaster.ca/dmc/
|cookedm at physics.mcmaster.ca