vector_shortcuts.py 文件源码

def unpad(matrix):
    '''
    Strip off a column (e.g. of ones). Transform from:
        array([[1., 2., 3., 1.],
               [2., 3., 4., 1.],
               [5., 6., 7., 1.]])
    to:
        array([[1., 2., 3.],
               [2., 3., 4.],
               [5., 6., 7.]])

    '''
    if matrix.ndim != 2 or matrix.shape[1] != 4:
        raise ValueError("Invalid shape %s: unpad expects nx4" % (matrix.shape,))
    if not all(matrix[:, 3] == 1.):
        raise ValueError('Expected a column of ones')
    return np.delete(matrix, 3, axis=1)