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bundles / scipy latest / scipy / fftpack / _helper / rfftfreq

function

scipy.fftpack._helper:rfftfreq

source: build-install/usr/lib/python3.14/site-packages/scipy/fftpack/_helper.py:11

Signature

def rfftfreq(n, d = 1.0)

Summary

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

Extended Summary

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

Parameters

n : int

Window length.

d : scalar, optional

Sample spacing. Default is 1.

Returns

out : ndarray

The array of length n, containing the sample frequencies.

Examples

import numpy as np
from scipy import fftpack
sig = np.array([-2, 8, 6, 4, 1, 0, 3, 5], dtype=float)
sig_fft = fftpack.rfft(sig)
n = sig_fft.size
timestep = 0.1
freq = fftpack.rfftfreq(n, d=timestep)
✓
freq
✗
array([0.  , 1.25, 1.25, 2.5 , 2.5 , 3.75, 3.75, 5.  ])

Aliases

  • scipy.fftpack.rfftfreq

Referenced by

This package

Other packages