its symmetric counterpart. When performing the
    final complex to real transform, the last value is thus treated as purely
    real. To avoid losing information, the correct shape of the real input
    **must** be given.

    Examples
    --------
    >>> a = np.zeros((3, 2, 2))
    >>> a[0, 0, 0] = 3 * 2 * 2
    >>> np.fft.irfftn(a)
    array([[[1.,  1.],
            [1.,  1.]],
           [[1.,  1.],
            [1.,  1.]],
           [[1.,  1.],
            [1.,  1.]]])

    r