Re: indexing expression performance

[Francesco Potortì]

>Also, Francesco, I forgot to do the obvious thing and test your examples
>with 3.1.51. At least on my machine, it looks like the performance has been
>reversed by the latest dense indexing improvements.
>
>octave:1> kk=rand(156,222,1,44,8);
>octave:2> t=cputime; for ii=1:44, for jj=1:8, mm=kk(:,:,:,ii,jj); endfor,
>endfor, cputime-t
>ans =  0.072004
>octave:3> cp=[1,cumprod(size(kk)(1:end-1))]; len=156*222; t=cputime; for
>ii=1:44, for jj=1:8,base=sum(([1,1,1,ii,jj]-1).*cp); mm=kk(base+1:base+len);
>endfor, endfor, cputime-t
>ans =  0.12401

Wonderful!  This will make my code more readable as soon as I upgrade :)

Thank you Jaroslav!

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