Re: accumarray

[David Bateman]

address@hidden wrote:
>   I would say that correct but slow code is better than no code at all.
>
>   Cheers,
>
>   Etienne
>
>   
Well, I'm back in the office and tried the accumarray in matlab for
speed and got the following results

vals = 1:1e4;
subs = randint(1e4,2,1024) + 1;
t = 0;
for i=1:10,
  t0 = cputime();
  A = accumarray (subs, vals, [1024,1024]);
  t = t + cputime() - t0;
end;
fprintf('Time %g s\n', t / 10);

MatlabR2007a
Time 0.016 s

Octave 2.9.12
Time 1.21592 s

So there is a factor of 76 difference in speed for this example. So
Etienne how useful is this function, and what portion of your simulation
time will be spent in it?

Cheers
David


-- 
David Bateman                                address@hidden
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