> From: Ryan May [mailto:[EMAIL PROTECTED] > Fago, Matt - AES wrote: > > I suppose the issue is: what is correct? Or is it a matter of > definition? [...] > Yeah, scaling by a factor of two for one-sided is definitely correct now > that I think about it. Note, however, that the scaling by the length is > not the problem. In fact, the current psd implementation does this > correctly when it corrects for the power in the window. The problem > stems from matlab scaling by the sampling frequency. Stoica and Moses > don't do this, nor does Welch 1967. I'm all for doing things in a > Matlab-compatible way--when they're correct. One of the reasons I > stopped using Matlab was that it tried to be too smart for me.
Yes, multiplying by 2/fs does look fairly good. Perhaps this comes about due to the Matlab implementation of the FFT? > > Note that the Matplotlib results also seem to have significantly less > > frequency resolution than > > the Matlab results. Is this the case, or am I not using noffset, nfft, > > and pad_to correctly? > > It's not that you're using those incorrectly, but rather that you failed > to notice that the default window is the Hanning window, not > rectangular. Try adding window=mlab.window_none to the call. (Sorry, I > meant to mention that before in my reply. Ah ... many thanks. Silly me. - Matt This e-mail and any files transmitted with it may be proprietary and are intended solely for the use of the individual or entity to whom they are addressed. If you have received this e-mail in error please notify the sender. Please note that any views or opinions presented in this e-mail are solely those of the author and do not necessarily represent those of ITT Corporation. The recipient should check this e-mail and any attachments for the presence of viruses. ITT accepts no liability for any damage caused by any virus transmitted by this e-mail. ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
