Re: BLAS lib performance (was Re: MPI (was Re: BIG libraries ....))

[Quentin Spencer]

Fredrik Lingvall wrote:

> I noticed that matlab utilizes that B=A*A'  (and A'*A) is symmetric 
> (A*A' only takes
> half the time to compute compared to A*A). Is this functionality 
> available in octave as well?


I haven't looked at the source code, but I think Octave doesn't do this 
automatically. I was recently comparing Octave with ATLAS libraries to 
Matlab, and I discovered that in Octave, Z=X*Y takes the same amount of 
time as Z=X*X', while in Matlab, the second is faster than the first.

-Quentin



-------------------------------------------------------------
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
-------------------------------------------------------------