MATLAB Programming

Analyzing Your Program’s Performance
Keep in mind that tic and toc measure overall elapsed time. Make sure that
no other applications are running in the background on your system that
could affect the timing of your MATLAB programs.
Measuring Smaller Programs
Shorter programs sometimes run too fast to get useful data from tic and toc.
When this is the case, try measuring the program running repeatedly in a
loop, and then average to find the time for a single run:
tic
for k = 1:100
-- run the program --
end
toc
Using tic and toc Versus the cputime Function
Although it is possible to measure performance using the cputime function,
it is recommended that you use the tic and toc functions for this purpose
exclusively. It has been the general rule for CPU-intensive calculations run
on Windows machines that the elapsed time using cputime and the elapsed
time using tic and toc are close in value, ignoring any first time costs.
There are cases however that show a significant difference between these
two methods. For example, in the case of a Pentium 4 with hyperthreading
running Windows, there can be a significant difference between the values
returned by cputime versus tic and toc.
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