Hi everyone,

Revisiting an issue which has already been discussed previously - in order
to check whether mlab.csd really does exactly what Matlab's cpsd is doing,
we wrote a couple of scripts, one in matlab and one in Python. They both run
on the attached data. The comparison of the results show that they are very
similar. However - two elements are off by a factor of approximately 2 - the
very first element and the very last. The last one may be off just because
it is very small, the difference between the two is tiny. But for the first
one - this is not the case - there is actually a difference in the values.
This is not only due to the fact that the DC component is very small,
because even if I add a DC component to the time-series, there is still
discrepancy of a factor of ~2 for that element. Does anyone have any idea
why this would be the case?

Thanks --

Ariel



-- 
Ariel Rokem
Helen Wills Neuroscience Institute
University of California, Berkeley
http://argentum.ucbso.berkeley.edu/ariel
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Attachment: compare_csd.py
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