Return indices for an inverse permutation.

    Parameters
    ----------
    indices : 1D np.ndarray with dtype=int
        Integer positions to assign elements to.

    Returns
    -------
    inverse_permutation : 1D np.ndarray with dtype=int
        Integer indices to take from the original array to create the
        permutation.

def inverse_permutation(indices):
    """Return indices for an inverse permutation.

    Parameters
    ----------
    indices : 1D np.ndarray with dtype=int
        Integer positions to assign elements to.

    Returns
    -------
    inverse_permutation : 1D np.ndarray with dtype=int
        Integer indices to take from the original array to create the
        permutation.
    """
    # use intp instead of int64 because of windows :(
    inverse_permutation = np.empty(len(indices), dtype=np.intp)
    inverse_permutation[indices] = np.arange(len(indices), dtype=np.intp)
    return inverse_permutation