Python numpy生成矩阵、串联矩阵代码分享

时间:2022-11-05 22:48:08

import numpy

生成numpy矩阵的几个相关函数:

numpy.array()
numpy.zeros()
numpy.ones()
numpy.eye()

串联生成numpy矩阵的几个相关函数:

numpy.array()
numpy.row_stack()
numpy.column_stack()
numpy.reshape()

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
>>> import numpy
>>> numpy.eye(3)
array([[ 1., 0., 0.],
    [ 0., 1., 0.],
    [ 0., 0., 1.]])
>>> numpy.zeros(3)
array([ 0., 0., 0.])
>>> numpy.ones(3)
array([ 1., 1., 1.])
>>> x1 = numpy.array((1, 2, 3))
>>> x1
array([1, 2, 3])
>>> x2 = numpy.array([4, 5, 6])
>>> x2
array([4, 5, 6])
>>> x3 = numpy.array((x1, x2))
>>> x3
array([[1, 2, 3],
    [4, 5, 6]])
>>> x4 = x3.reshape(2, 3)
>>> x4
array([[1, 2, 3],
    [4, 5, 6]])
>>> x4 = x3.reshape(3, 2)
>>> x4
array([[1, 2],
    [3, 4],
    [5, 6]])
>>> x5 = numpy.row_stack(x1, x2)
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
TypeError: vstack() takes exactly 1 argument (2 given)
>>> x5 = numpy.row_stack((x1, x2))
>>> x5
array([[1, 2, 3],
    [4, 5, 6]])
>>> x6 = numpy.row_stack([x1, x2])
>>> x6
array([[1, 2, 3],
    [4, 5, 6]])
>>> x7 = numpy.row_stack((x6, x2))
>>> x7
array([[1, 2, 3],
    [4, 5, 6],
    [4, 5, 6]])
>>> x7[0]
array([1, 2, 3])
>>> x7[1]
array([4, 5, 6])
>>> x7[2]
array([4, 5, 6])
>>> x8 = numpy.column_stack([x1, x2, x1, x2])
>>> x8
array([[1, 4, 1, 4],
    [2, 5, 2, 5],
    [3, 6, 3, 6]])
>>> x8[0]
array([1, 4, 1, 4])
>>> x8[1]
array([2, 5, 2, 5])
>>> x8[2]
array([3, 6, 3, 6])
>>> x8[3]
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
IndexError: index 3 is out of bounds for axis 0 with size 3
>>> x8[0][3]
4
>>>

python生成1行四列全2矩阵

?
1
print np.ones((1,4))*2

总结

以上就是本文关于Python numpy生成矩阵、串联矩阵代码分享的全部内容,希望对大家有所帮助。感兴趣的朋友可以继续参阅本站其他相关专题,如有不足之处,欢迎留言指出。感谢朋友们对本站的支持!

原文链接:http://blog.csdn.net/garfielder007/article/details/51373683