numpy flatten

latten是numpy.ndarray.flatten的一个函数 

import numpy as np
a = np.zeros((2,3,4))
print(a.shape)
print(a.flatten().shape)
# (2, 3, 4)
# (24,)

可以看到，它把 2*3*4的数组变成了1*24的数组

flatten函数就是将数组折叠称一维的输出

a = [[2, 3, 4], [5, 6, 7]]
a = np.array(a)
print(a)
print(a.size)
print(a.flatten().shape)
print(a.flatten())
#[[2 3 4]
# [5 6 7]]
#6
#(6,)
#[2 3 4 5 6 7]