Numpy库 np.c_ np.r_用法解析

np.c_和np.r_用于把两个矩阵连接起来
连接方式为

np.c_

$A=\left[ \begin{matrix} 1 & 2 \\ 3 & 4 \end{matrix} \right]\quad B=\left[ \begin{matrix} 5 & 6 \\ 7 & 8 \end{matrix} \right]$
$C=\left[ \begin{matrix} 1 & 2 &5&6\\ 3 & 4&7&8 \end{matrix} \right]\quad$

import numpy as np

A = np.array([[1, 2], [3, 4]])
B = np.array([[5, 6], [7, 8]])
C = np.c_[A, B]
print(C)
Out:
[[1 2 5 6]
 [3 4 7 8]]

np.r_

$A=\left[ \begin{matrix} 1 & 2 \\ 3 & 4 \end{matrix} \right]\quad B=\left[ \begin{matrix} 5 & 6 \\ 7 & 8 \end{matrix} \right]$
$D=\left[ \begin{matrix} 1 & 2 \\ 3 & 4\\ 5 & 6 \\ 7 & 8 \end{matrix} \right]$

import numpy as np

A = np.array([[1, 2], [3, 4]])
B = np.array([[5, 6], [7, 8]])
D = np.r_[A, B]
print(D)
Out:
[[1 2]
 [3 4]
 [5 6]
 [7 8]]