Question

python中如何在矩阵中添加一列或是一行？？

如图所示，有三个矩阵，现在想把这三个矩阵合并为一个矩阵，它们分别为合并后的矩阵的第一二三列，这该如何编程和操作，求大神指导？？？
如果是行的话，又该怎么操作？

Answer 1

例如文件t.data数据格式如下 1，2，3 4，5，6 7，8，9 //读入文件 file=open("t.data","r") //初始化矩阵 matrix=[] //读入数据并加到矩阵中 for line in file: line.strip() matrix.append(line.split(',')) //打印 print(matrix)

Answer 2

>>> import numpy as np
>>> a = np.arange(1,11).reshape(10,1)
>>> b = a * 1.1
>>> c = a / 1.1
>>> a
array([[ 1],
       [ 2],
       [ 3],
       [ 4],
       [ 5],
       [ 6],
       [ 7],
       [ 8],
       [ 9],
       [10]])
>>> b
array([[  1.1],
       [  2.2],
       [  3.3],
       [  4.4],
       [  5.5],
       [  6.6],
       [  7.7],
       [  8.8],
       [  9.9],
       [ 11. ]])
>>> c
array([[ 0.90909091],
       [ 1.81818182],
       [ 2.72727273],
       [ 3.63636364],
       [ 4.54545455],
       [ 5.45454545],
       [ 6.36363636],
       [ 7.27272727],
       [ 8.18181818],
       [ 9.09090909]])
>>> x = np.array([
...     np.reshape(a, len(a)),
...     np.reshape(b, len(b)),
...     np.reshape(c, len(c))
...     ]).transpose()
>>> x
array([[  1.        ,   1.1       ,   0.90909091],
       [  2.        ,   2.2       ,   1.81818182],
       [  3.        ,   3.3       ,   2.72727273],
       [  4.        ,   4.4       ,   3.63636364],
       [  5.        ,   5.5       ,   4.54545455],
       [  6.        ,   6.6       ,   5.45454545],
       [  7.        ,   7.7       ,   6.36363636],
       [  8.        ,   8.8       ,   7.27272727],
       [  9.        ,   9.9       ,   8.18181818],
       [ 10.        ,  11.        ,   9.09090909]])
>>>

is it?

Answer 3

a = [[1],
[2],
[3]]
b = [[4],
[5],
[6]]
c = [[7],
[8],
[9]]
res = map(lambda x,y,z: [x[0],y[0],z[0]], a, b, c)
print res

如果是行的话：
a = [[1,2,3]]
b = [[4,5,6]]
c = [[7,8,9]]
res = a+b+c
print res

Answer 4

np.hstack