John Hunter wrote: > On 10/2/07, Lars Friedrich <[EMAIL PROTECTED]> wrote: >> Hello all, >> >> I am using matplotlib.mlab.psd to find power spectra of measured data. >> Sometimes it happens that I use the automatic zero padding (if the >> length of my measured data is smaller than nFFT) and detrending >> (pylab.detrend_mean) at the same time. >> >> I think that the psd-algorithm does the zero padding *first* and *then* >> uses the detrend function. >> >> For my application this is not good because it introduces low-frequency >> signals that I can see in the spectrum. So the detrending does not work >> as good as it does when there is no zero padding. >> >> What is the reason for this order of applying zero padding and >> detrending? Wouldn't it make sense to change it? > > I wrote this function many years ago and do not remember why I choose > the order pad then detrend, but what you propose makes sense, so let's > let this percolate for a bit and if noone objects I will change it > (and related functions).
The change makes sense to me also. Eric ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
