[Numpy-discussion] site.cfg: Custom BLAS / LAPACK configuration

[Dag Sverre Seljebotn]

On 12/13/2012 07:59 PM, David Cournapeau wrote:
> On Fri, Dec 7, 2012 at 7:58 PM, Dag Sverre Seljebotn
> <d.s.seljebotn at astro.uio.no> wrote:
>> One way of fixing this I'm sort of itching to do is to create a
>> "pylapack" project which can iterate quickly on these build issues,
>> run-time selection of LAPACK backend and so on. (With some templates
>> generating some Cython code it shouldn't be more than a few days for an
>> MVP.)
>>
>> Then patch NumPy to attempt to import pylapack (and if it's there, get a
>> table of function pointers from it).
>>
>> The idea would be that powerusers could more easily build pylapack the
>> way they wanted, in isolation, and then have other things switch to that
>> without a rebuild (note again that it would need to export a table of
>> function pointers).
>>
>> But I'm itching to do too many things, we'll see.
>
> It would be hard to support in a cross platform way I think (windows
> being the elephant in the room). I would be more than happy to be
> proven wrong, though :)

Right, perhaps I should have said "Linux users" rather than "power 
users" :-)

But seriously, I'd like to have a few more details here.

Is it something about calling conventions and "libc" and so on that 
makes the function-pointer-table approach difficult? (But the NumPy C 
API is exported in the same way?)

Or is it about the build? Can't one just lift whatever numpy.distutils 
or the NumPy Bento build does for detection? Though what I'll aim for at 
first is the complete opposite, no auto-detection, but a Windows user 
should also be able to specify the right flags manually...


Dag Sverre