From maintainers-request at octave dot org Sat Jan 29 19:30:25 2005
Subject: min function very slow?
From: Daniel J Sebald <daniel dot sebald at ieee dot org>
To: maintainers at octave dot org
Date: Sat, 29 Jan 2005 19:36:13 -0600

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My eyes are deceiving me.  I came across a slow loop and to my surprise 
traced it to the min function.  But I'm wondering how this can be 
because I looked through the source code and the min/max commands inside 
minmax.cc and dNDArray.cc look identical except obviously for the change 
in sign when testing order.  I have a fairly recent version of 2.1.64.

I put together a little test script.  Someone please try the attached 
script.  My result is

octave:1> minmaxtime
looptime = 0.044205
maxtime = 0.081752
mintime = 7.5832

Thank you,

Dan


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 filename="minmaxtime.m"

N_loop = 1000;
tic()
for i=1:N_loop
  j = i;
end
looptime = toc()
for i=1:N_loop
  j = max(i);
end
maxtime = toc() - looptime
for i=1:N_loop
  j = min(i);
end
mintime = toc() - maxtime

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