剪切一个numpy数组

在该方法tom10的回答可以扩展到任意尺寸：

def shear3(a, strength=1, shift_axis=0, increase_axis=1):    if shift_axis > increase_axis:        shift_axis -= 1    res = numpy.empty_like(a)    index = numpy.index_exp[:] * increase_axis    roll = numpy.roll    for i in range(0, a.shape[increase_axis]):        index_i = index + (i,)        res[index_i] = roll(a[index_i], -i * strength, shift_axis)    return res