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in reply to Re^3: Finding local maxima/minima in noisy, pediodic data
in thread Finding local maxima/minima in noisy, pediodic data

With any sort of filter (moving average or low pass) you will induce a delay on the response. That is to say, if you're at a peak in the filtered data and want to match it with the original data, you will need to look back a fixed period of time.

For what it's worth, I think the low pass filter will be much more applicable to your goal since the noise is high frequency periodic. The alpha I provided above does a fine job smoothing out the noise but leaving the pulses of the desired frequency.