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## Re: min function very slow?

 From: John W. Eaton Subject: Re: min function very slow? Date: Sun, 30 Jan 2005 01:55:39 -0600

```On 30-Jan-2005, Daniel J Sebald <address@hidden> wrote:

| On second thought, your hypothesis seems correct.  rand() and randn()
| are similar to max/min, being in the same file.  I rewrote the function
| with rand/randn and got similar behavior:
|
| octave:1> [loopt, randt, randnt] = rrt(10000)
| loopt = 0.10696
| randt = 0.36079
| randnt = 0.35501
| octave:2> [loopt, randt, randnt] = rrt(10000)
| loopt = 0.10461
| randt = 0.34843
| randnt = 7.3243

If you get results like this, then I suspect your function is still
computing the time differences incorrectly.  Try something like

function [looptime,maxtime,mintime]=mmt(N_loop)
t = zeros(4,1);
k=1
t(k++) = cputime();
for i=1:N_loop
j = i;
end
t(k++) = cputime();
for i=1:N_loop
j = min(i);
end
t(k++) = cputime();
for i=1:N_loop
j = max(i);
end
t(k++) = cputime();
x = diff (t);
looptime = x(1);
maxtime = x(2);
mintime = x(3);
endfunction

Your original function used toc() incorrectly.  It always returns the
time since the last call to tic().

jwe

```

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