prtools.shift#

shift(a, shift)[source]#

Shift an array via FFT.

Shift an array by (row, column). The shifts may be non-integer as the shift operation is implemented by introducing a Fourier-domain tilt. If a is complex, the result will also be complex.

Parameters:

a (array_like) – The input array.
shift ((2,) sequence) – The shift specified as (row, column).

Returns:

shifted – The shifted input array.

Return type:

ndarray

Example

>>> arr = np.zeros((3,3))
>>> arr[2,2] = 1
>>> arr
array([[0., 0., 0.],
       [0., 0., 0.],
       [0., 0., 1.]])
>>> arr_shift = prtools.shift(arr, shift=(-1,-1))
>>> arr_shift
array([[ 0.00000000e+00, -7.40148683e-17, -2.46716228e-17],
       [-1.16747372e-16,  1.00000000e+00,  2.14548192e-16],
       [-3.12823642e-17,  2.22044605e-16, -4.18468327e-17]])