numpy.reshape(-1,1)的具体使用_python

x = np.array([[2, 0], [1, 1], [2, 3]])

y = x.reshape(3,2)
 
y
Out[43]: 
array([[2, 0],
       [1, 1],
       [2, 3]])

y = x.reshape(-1,1)
 
y
Out[34]: 
array([[2],
       [0],
       [1],
       [1],
       [2],
       [3]])

y = x.reshape(-1,2)
 
y
Out[37]: 
array([[2, 0],
       [1, 1],
       [2, 3]])

y = x.reshape(1,-1)
 
y
Out[39]: array([[2, 0, 1, 1, 2, 3]])

y = x.reshape(2,-1)
 
y
Out[41]: 
array([[2, 0, 1],
       [1, 2, 3]])

e = np.array([1]) #只包含一个数据
f = e.reshape(1,-1) #改变形状，输出f之后发现它已经变成了二维数据

import numpy as np
a = np.array([[1,2,3],[4,5,6]]) #是两行三列的数据，二维
b = np.array([1,2])    #是一维数据
c = b.reshape(-1,1)    #c已经变成了二维数据，变成了两行一列
d = b.reshape(1,-1)    #d变成了一行两列的数据，
print('b.shape is {0}'.format(b.shape))
print(b)
print('c.shape is {0}'.format(c.shape))
print(c)
print('d.shape is {0},d array is {1}'.format(d.shape,d))