Comments on: Nested Timing http://blogs.mathworks.com/loren/2009/01/06/nested-timing/ Loren Shure works on design of the MATLAB language at MathWorks. She writes here about once a week on MATLAB programming and related topics. Thu, 09 Feb 2012 04:19:21 +0000 hourly 1 http://wordpress.org/?v=3.2.1 By: Roy http://blogs.mathworks.com/loren/2009/01/06/nested-timing/#comment-29956 Roy Tue, 13 Jan 2009 04:06:58 +0000 http://blogs.mathworks.com/loren/2009/01/06/nested-timing/#comment-29956 for long operations I prefer the output in a datestr format and not just raw seconds. This is mostly for jobs that take more than an hour. This is my timing pattern: <pre> t0=now; for i=1:1000 % do some stuff fprintf('iter: %d time:%s\n',i,datestr(now-t0,13)); end </pre> for long operations I prefer the output in a datestr format and not just raw seconds. This is mostly for jobs that take more than an hour. This is my timing pattern: 

t0=now;
for i=1:1000
   % do some stuff
   fprintf('iter: %d time:%s\n',i,datestr(now-t0,13));
end
]]> By: Gautam Vallabha http://blogs.mathworks.com/loren/2009/01/06/nested-timing/#comment-29948 Gautam Vallabha Wed, 07 Jan 2009 15:50:49 +0000 http://blogs.mathworks.com/loren/2009/01/06/nested-timing/#comment-29948 We can now calculate the overhead of tic/toc using tic/toc :) <pre> function tictoc t = tic; for i=1:1e5 t2 = tic; ignore=toc(t2); % suppress output end % convert to millisec overhead = (toc(t)/1e5)*1e3 </pre> The overhead value I get (on my 1.8 GHz dual core Intel) is 0.0124 milliseconds. Not bad! We can now calculate the overhead of tic/toc using tic/toc :)

function tictoc
t = tic;
for i=1:1e5
    t2 = tic;
    ignore=toc(t2); % suppress output
end
% convert to millisec
overhead = (toc(t)/1e5)*1e3

The overhead value I get (on my 1.8 GHz dual core Intel) is 0.0124 milliseconds. Not bad!

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