jax.numpy.fft.rfftfreq(n, d=1.0, *, dtype=None)[source]#

Return the Discrete Fourier Transform sample frequencies

LAX-backend implementation of numpy.fft.rfftfreq().

Original docstring below.

(for usage with rfft, irfft).

The returned float array f contains the frequency bin centers in cycles per unit of the sample spacing (with zero at the start). For instance, if the sample spacing is in seconds, then the frequency unit is cycles/second.

Given a window length n and a sample spacing d:

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

Unlike fftfreq (but like scipy.fftpack.rfftfreq) the Nyquist frequency component is considered to be positive.

  • n (int) – Window length.

  • d (scalar, optional) – Sample spacing (inverse of the sampling rate). Defaults to 1.

  • dtype (Optional) – The dtype of the returned frequencies. If not specified, JAX’s default floating point dtype will be used.


f – Array of length n//2 + 1 containing the sample frequencies.

Return type: