操纵numpy matrices ..替换一个值

Question

我最近发现了numpy及其在矩阵方面的用处。还有一件事让我感到困扰。如何使用所需的值替换矩阵中的特定值。我试过＆gt;

matrix1 = np.zeros([10,10])
replacewith = 1
atposition = np.array(5,5)
matrix1[atposition] = replacewith

所以我要做的就是用1替换中间的0。 谢谢！

Answer 1

import numpy as np
matrix1 = np.zeros([10,10])
replacewith = 1
atposition = (5,5)
matrix1[atposition] = replacewith
print matrix1

输出：

[[ 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.  0.  0.  0.  0.  0.  0.  0.  0.]
 [ 0.  0.  0.  0.  0.  1.  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.  0.  0.]]