AR,
although floating point operations follow a standard (commonly IEEE
754-1985), they are not associative. Thus, based on the order in which
operations are performed, you may end up with different results.
You can check this out on wikipedia:
http://en.wikipedia.org/wiki/Floating_point
Alfredo
On Tue, 2008-05-20 at 10:27 -0400, Adarsh Binani wrote:
Hi:
Could you please clarify why I get different results at times using
different Machine-specific optimized BLAS libraries. I do understand
that these are from different vendors, and are machine specific, but I
am not sure why we still get different results when floating point
arithmetic is standardized?
Thanks
AR
--
Alfredo Buttari, PhD
Institut National de Recherche en
Informatique et en Automatique (INRIA)
Laboratoire de l'Informatique du Parall?lisme (LIP)
?cole Normale Sup?rieure de Lyon
46 All?e d'Italie 69364 Lyon Cedex 07 - France
http://alfredobuttari.wordpress.com
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