Re: False alarm (Re: reshape slowdown?)

[David Bateman]

Dmitri,

>  John W. Eaton wrote:
> ...
> > Transpose is not implemented with lapack or blas functions.  I suppose
> > it could be due to changing from 2-d to N-d arrays, but I don't see
> > anything obvious that would account for a slowdown.
> > 
>
> On Athlon MP 2000 MHz:
>
> octave:3> s=rand(3000);
> octave:4> tic; a=s'; toc
> ans = 1.9846
>
> On Athlon XP 1666 MHz -> 0.9 second.
> The only difference between those machines
> is lapack library...
> Also on MP computer the time was almost 1/2 of that
> back in June (octave.2.1.57)...
>
> I am still looking at it, but I am really puzzled.



It seems you've fall on the same problem as my colleague Laurent came 
across, though he identified it as happening with the fft function I 
believe. In any case I came confirm this is an issue... Though last I 
heard Laurent was as lost as you.

Regards
David

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