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From: | edA-qa mort-ora-y |
Subject: | Re: Finding peaks/max in a graph |
Date: | Mon, 05 Apr 2004 19:04:48 +0200 |
User-agent: | Mozilla Thunderbird 0.5 (X11/20040208) |
Joe Koski wrote:
Another routine called extr.m that calculates both extrema and zero crossings is at http://perso.ens-lyon.fr/patrick.flandrin/emd.html That routine is part of a package based on the Empirical Mode Decomposition approach that does, in my opinion, a much better job of finding frequency content of a signal than the classical fft approach. The fft assumes that signals are strictly periodic and stationary, EMD does not.
Thank you, this goes a lot faster, though it finds different peaks for some reason (the largest peaks it finds just the same, but smaller ones not, maybe somethign to do withs its noise checking).
I tried to look at this full pacakge, but the code didn't all work in Octave, and I'm not clear how to do what I want with the functions -- I just want peak frequencies from a waveform as I said before...
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