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# scipy.fftpack.rfftfreq

`scipy.fftpack.``rfftfreq`(n, d=1.0)

  rfftfreq(n, d=1.0) -> f

  DFT sample frequencies (for usage with rfft,irfft).

  The returned float array contains the frequency bins in cycles/unit (with zero at the start) given a window length n and a sample spacing d:

  > f = [0,1,1,2,2,...,n/2-1,n/2-1,n/2]/(d*n) if n is even f = [0,1,1,2,2,...,n/2-1,n/2-1,n/2,n/2]/(d*n) if n is odd

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