numpy之填充函数pad
- 使用方法
numpy.pad(array, pad_width, mode, **kwargs)[source]
array表示待填充编内距的矩阵;
pad_width表示在每个矩阵上的填充宽度;
mode表示填充模式
- 示例:
>>> a
array([ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11])
>>> a_pad=np.pad(a,(2,),mode='constant', constant_values=0)
>>> a_pad
array([ 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 0, 0])
>>> b=a.reshape(2,2,3)
>>> b
array([[[ 0, 1, 2],
[ 3, 4, 5]],
[[ 6, 7, 8],
[ 9, 10, 11]]])
>>> b_pad=np.pad(b,((0,),(2,),(3,)),mode='constant',constant_values=0)
>>> b_pad
array([[[ 0, 0, 0, 0, 0, 0, 0, 0, 0],
[ 0, 0, 0, 0, 0, 0, 0, 0, 0],
[ 0, 0, 0, 0, 1, 2, 0, 0, 0],
[ 0, 0, 0, 3, 4, 5, 0, 0, 0],
[ 0, 0, 0, 0, 0, 0, 0, 0, 0],
[ 0, 0, 0, 0, 0, 0, 0, 0, 0]],
[[ 0, 0, 0, 0, 0, 0, 0, 0, 0],
[ 0, 0, 0, 0, 0, 0, 0, 0, 0],
[ 0, 0, 0, 6, 7, 8, 0, 0, 0],
[ 0, 0, 0, 9, 10, 11, 0, 0, 0],
[ 0, 0, 0, 0, 0, 0, 0, 0, 0],
[ 0, 0, 0, 0, 0, 0, 0, 0, 0]]])