 form of zero
    padding is desired, it must be performed before `ifft2` is called.

    Examples
    --------
    >>> import scipy.fft
    >>> import numpy as np
    >>> x = 4 * np.eye(4)
    >>> scipy.fft.ifft2(x)
    array([[1.+0.j,  0.+0.j,  0.+0.j,  0.+0.j], # may vary
           [0.+0.j,  0.+0.j,  0.+0.j,  1.+0.j],
           [0.+0.j,  0.+0.j,  1.+0.j,  0.+0.j],
           [0.+0.j,  1.+0.j,  0.+0.j,  0.+0.j]])

    r