`scipy.ndimage._fourier:fourier_shift`

source: build-install/usr/lib/python3.14/site-packages/scipy/ndimage/_fourier.py:253

Signature

def fourier_shift(input, shift, n = -1, axis = -1, output = None)

Summary

Multidimensional Fourier shift filter.

Extended Summary

The array is multiplied with the Fourier transform of a shift operation.

Parameters

input : array_like: The input array.
shift : float or sequence: The size of the box used for filtering. If a float, shift is the same for all axes. If a sequence, shift has to contain one value for each axis.
n : int, optional: If n is negative (default), then the input is assumed to be the result of a complex fft. If n is larger than or equal to zero, the input is assumed to be the result of a real fft, and n gives the length of the array before transformation along the real transform direction.
axis : int, optional: The axis of the real transform.
output : ndarray, optional: If given, the result of shifting the input is placed in this array.

Returns

fourier_shift : ndarray: The shifted input.

Examples

from scipy import ndimage, datasets
import matplotlib.pyplot as plt
import numpy.fft
fig, (ax1, ax2) = plt.subplots(1, 2)
plt.gray()  # show the filtered result in grayscale
ascent = datasets.ascent()
input_ = numpy.fft.fft2(ascent)
result = ndimage.fourier_shift(input_, shift=200)
result = numpy.fft.ifft2(result)

✓

ax1.imshow(ascent)
ax2.imshow(result.real)  # the imaginary part is an artifact

✗

<matplotlib.image.AxesImage object at 0x7f3f59eeb610>

plt.show()

✓

Aliases

scipy.ndimage.fourier_shift