From help-octave-request at bevo dot che dot wisc dot edu Thu Dec 18 13:58:39 2003 Subject: Re: Octave QR factorization From: Ross Vandegrift To: "John W. Eaton" Cc: help-octave at bevo dot che dot wisc dot edu Date: Thu, 18 Dec 2003 14:55:40 -0500 On Wed, Dec 17, 2003 at 06:19:00PM -0600, John W. Eaton wrote: > | The script does fail on my AMD Thunderbird, but I ignored the ATLAS > | warnings and build with 3DNow - burning speed was more important to me > | ::-) > > I remember using a 3DNow! version of lapack/blas on an Athlon and > getting completely wrong results. Unfortunately I don't remember the > details and I never tracked down the real cause. Maybe the problems I > had have been fixed by now. OTOH, if you want answers fast and don't > care whether they are right, I'm sure that I can write some code that > will get them to you faster than ATLAS with 3DNow! Hehe, not such a big deal - it was just for a course in numerical analysis (what led me to Octave, actually). Any times when numerical error, ill-conditioning, etc., were a problem, they were a problem because the instructor wanted it that way and we had to be smarter. -- Ross Vandegrift ross at willow dot seitz dot com A Pope has a Water Cannon. It is a Water Cannon. He fires Holy-Water from it. It is a Holy-Water Cannon. He Blesses it. It is a Holy Holy-Water Cannon. He Blesses the Hell out of it. It is a Wholly Holy Holy-Water Cannon. He has it pierced. It is a Holey Wholly Holy Holy-Water Cannon. He makes it official. It is a Canon Holey Wholly Holy Holy-Water Cannon. Batman and Robin arrive. He shoots them. ------------------------------------------------------------- Octave is freely available under the terms of the GNU GPL. Octave's home on the web: http://www.octave.org How to fund new projects: http://www.octave.org/funding.html Subscription information: http://www.octave.org/archive.html -------------------------------------------------------------