Numpy 笔记

transpose

numpy.transpose(a, axes=None)
#修改张量的维度
>>> x = np.arange(4).reshape((2,2))
>>> x
array([[0, 1],
       [2, 3]])
>>> np.transpose(x)
array([[0, 2],
       [1, 3]])
>>> x = np.ones((1, 2, 3))
>>> np.transpose(x, (1, 0, 2)).shape
(2, 1, 3)

nonzero

找到非零元素的下标

where

np.where(x<0,0,x) #分段函数