numpy数组扩展函数repeat和tile用法

numpy.repeat(a, repeats, axis=None)

>>> a = np.arange(3)
>>> a
array([0, 1, 2])
>>> np.repeat(a, 2)
array([0, 0, 1, 1, 2, 2])


>>> a = np.array([[1,2],[3,4]])
>>> a
array([[1, 2],
       [3, 4]])
>>> np.repeat(a, 2, 1)
array([[1, 1, 2, 2],
       [3, 3, 4, 4]])

>>> np.repeat(a, 2, 0)
array([[1, 2],
       [1, 2],
       [3, 4],
       [3, 4]])

tile函数功能：对整个数组进行复制拼接

>>> a
array([[1, 2],
       [3, 4]])
>>> np.tile(a, 2)
array([[1, 2, 1, 2],
       [3, 4, 3, 4]])