关于Numpy中的行向量和列向量详解

import numpy as np
b=np.array([1,2,3]).reshape((1,-1))
print(b,b.shape)

(array([[1, 2, 3]]), (1, 3))

import numpy as np
b=np.array([[1,2,3]]) #两层'[]'
print(b,b.shape)

(array([[1, 2, 3]]), (1, 3))

import numpy as np
a=np.array([1,2,3]).reshape((-1,1))
print(a,a.shape)

(array([[1],
    [2],
    [3]]), (3, 1))

import numpy as np
a=np.array([[1,2,3]]).T
print(a,a.shape)

(array([[1],
    [2],
    [3]]), (3, 1))