Re: ATLAS and octave

[John W. Eaton]

On 10-Feb-2000, chenu-tournier marc <address@hidden> wrote:

| R=0;x=rand(512,1)+j*rand(512,1);
| t=cputime;R=R+x*x';;cputime-t
| 
| I have lost some time!
| 
| normal octave gives .3 sec
| Altas ocatve  gives .4 sec
| 
| Can you confirm this and do you have an idea why  this happens?

Is this result repeatable?  What is the average over 100 runs?

512 elements is quite small compared to the 1e6 elements in the
1000x1000 example.  The overhead of setting up the calculation is much
more likely to be the dominant factor for small examples.

jwe



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