One dimensional vector transpose point multiplication np dot

import numpy as np
a = np.array([1, 2])
a.shape = (1,2)# The second latitude 1 It's empty. , Only when it is specified can the row vector be converted into column vector smoothly 
print(a)
print(a.transpose())
print(np.dot(a,a.transpose()))

print("**************************")
c = np.array([1, 2])
b = c.reshape(len(c),1)# Put the vector reshape once , In this way, the purpose of one-dimensional vector and one-dimensional vector transpose and multiply as a matrix 
print(b.shape)
print(b)