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). JDH ------------------------------------------------------------------------- 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
