改变数组某几行某列的值
import numpy as np
a = np.zeros([4,3])
print('前a:', a)
a[0:3, 1] = 1 # 数组行(0,1,2)和列(1)的值变为1
print('后a:', a)
结果:
前a: [[0. 0. 0.]
[0. 0. 0.]
[0. 0. 0.]
[0. 0. 0.]]
后a: [[0. 1. 0.]
[0. 1. 0.]
[0. 1. 0.]
[0. 0. 0.]]