Extraction frequency and amplitude from FFT

When you have your spectrum given as a signal (a FlexPro object with frequency as x component) you can use the FPScript function Extrema() to locate the local maximas, sort them in descending order and output the first three elements:

[code]
Dim data = ChannelSpektrum
Dim hyst = 0.05 * Range(data)
Dim ind = Extrema(data, hyst, EVENT_POSITIVE)
Dim ext = data[ind]
Sort(ext, SORT_Y+SORT_DESCENDING)[0,2]
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