Extraction frequency and amplitude from FFT

[Damian Pietrusiak]

My aim is to find the amplitude and frequency of the 3 highest maxima from FFT in defined frequency range.
I tried Maximum function but as a result I got only amplitude without frequency.
I am looking for tool which give me both components (frequency and amplitude).
I need that to write those information to some table/txt or similar.

Thank you in advance for any hints !!!

[Damian Pietrusiak]

My aim is to find the amplitude and frequency of the 3 highest maxima from FFT in defined frequency range.
I tried Maximum function but as a result I got only amplitude without frequency.
I am looking for tool which give me both components (frequency and amplitude).
I need that to write those information to some table/txt or similar.

Thank you in advance for any hints !!!

[Bernhard Kantz]

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]
[/code]

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