如何将二维数组更改为一维

Question

I am trying to change a two dimensional array to one dimensional, my code is like this:

x = np.array([[1, 2, 4], [3, 4], [1,2,3,4,5,6,7]])
x = x.flatten()

however, I found that flatten function works well on

x = np.array([[1, 2], [3, 4]])

but it does not work on

x = np.array([[1, 2, 4], [3, 4], [1,2,3,4,5,6,7]])

could anyone help me to change

np.array([[1, 2, 4], [3, 4], [1,2,3,4,5,6,7]]) 

to

np.array([[1, 2, 4, 3, 4, 1,2,3,4,5,6,7])

thank you

Answer 1

您可以尝试使用concatenate （ numpy文档 ）：

flatten_x = np.concatenate(x)

Answer 2

temp = []
for i in x:
   for j in i:
       temp.append(j)

x = np.array(temp)

Hope this will do it.

Answer 3

Use the following simple code.

import numpy as np

x = np.array([[1, 2, 4], [3, 4], [1,2,3,4,5,6,7]])
y = sum(x.tolist(),[])
print(np.array(y))