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lapack and blas

Greetings, and thank you for the lapack package!

I'd like to package atlas before the upcoming release in November.  As
you may know, atlas tunes blas for your system automatically, with
rather impressive results, turning the reference blas implementation
essentially into an open source per-system optimized implementation.
As I'm working on scalapack too, I'd like to get a blas library in
shared, as well as in static form.  (Using static libs in scalapack
*really* wastes space).  I've put together a BLAS package, and an
atlas package, providing both shared and static libs.  An idea is to
also provide a script in atlas which would rebuild the blas library
provided by the blas package with the newly optimized routines.  That
way, programs dynamically linked against libblas won't need to be
recompiled to use atlas.  To do this, of course, requires that the
static library be built with -fPIC.  Another idea is to use the
alternatives system to allow on the fly switching between blas libs.

What are your thoughts here?  Assuming you are in general agreement
with the above ideas, Here are the options as I see them, in ascending
order of time required to accomplish:

1) Just don't include BLAS in lapack, and make a dependency on libblas
   in the control file.

2) Incorporate my Makefile to get shared and static blas libraries
   built with lapack.  It might then be nice to make sure the reset of
   lapack uses the shared library.

3) Do 2), and then add the update-alternatives calls into postinst.  I
   could help here if needed.  Perhaps the reference implementation,
   whether in a separate package or part of lapack, could be
   libblas_ref, and the atlas one libblas_atlas, with appropriate
   links set to libblas.  Since these libs are binary compatible, the
   soname of all libs should be libblas.so.x.

The last option is probably "the right thing to do"TM, whether we
decide that or not is another question.

Thanks again!  I hope you don't mind me cc'ing this note to the
debian-beowulf mailing list, to solicit some additional feedback.

Take care,

Camm Maguire			     			camm@enhanced.com
"The earth is but one country, and mankind its citizens."  --  Baha'u'llah

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