How to restrict the Max Peak Height of findpeaks

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I've managed to set a minimum peak height when plotting some data and finding the peaks but is there a function I can ue to set a max peak height? I can't seem to find one.
As you can see the errors are quite large. My code is as follows:
figure(nF)
findpeaks(ResAcceltrim,'MinPeakDistance',300,'MinPeakHeight',pe);
pks=findpeaks(ResAcceltrim,'MinPeakDistance',300,'MinPeakHeight',pe);
pks=pks(1:20,1);

Accepted Answer

Image Analyst
Image Analyst on 12 Oct 2015
If you don't want it to find peaks higher than some amount, just set those elements equal to the min. Actually it would be better to find the peaks and then "fall down" the peaks until they turn up again and then interpolate in from both sides, but that's more complicated even though it would be better. Maybe this simple way will do the job for you:
minValue = min(yourSignal);
tallPeakIndexes = yourSignal > someThreshold; % Whatever value you want.
yourSignal(tallPeakIndexes) = minValue; % Or you can use someThreshold instead of minValue.
If that ends up finding spurious peaks at the edges of the flattened peak, then use the more robust second method I suggested.

More Answers (1)

dpb
dpb on 12 Oct 2015
You're correct there is no such facility built into findpeaks--one would normally think a large peak would be agoodthing(tm), not something to be avoided.
You'll have to simply test and exclude results from the returned search that exceed the rest by some magnitude (either absolute or as a percentage). Typical tests for outliers might be a ploy to consider in doing so unless you have other ways to decide what is "noise".

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