numpy.ndarray.flatten()函数的具体使用

import numpy as np


class Debug:
    def __init__(self):
        self.array1 = np.array([[1, 2], [3, 4]])
        self.array2 = np.ones((2, 2, 2))

    def mainProgram(self):
        print("The value of array1 is: ")
        print(self.array1)
        print("The value of flattened array is: ")
        array2 = self.array1.flatten()
        print(array2)
        print("The value of array2 is: ")
        print(self.array2)
        print("The value of flattened array is: ")
        print(self.array2.flatten())


if __name__ == '__main__':
    main = Debug()
    main.mainProgram()
"""
The value of array1 is: 
[[1 2]
 [3 4]]
The value of flattened array is: 
[1 2 3 4]
The value of array2 is: 
[[[1. 1.]
  [1. 1.]]

 [[1. 1.]
  [1. 1.]]]
The value of flattened array is: 
[1. 1. 1. 1. 1. 1. 1. 1.]
"""

>>> x = np.array([[1, 2], [3, 4]])
>>> x
array([[1, 2],
       [3, 4]])
>>> x.flatten()
array([1, 2, 3, 4])
>>> x.ravel()
array([1, 2, 3, 4])
 
# 两者默认均是行序优先
>>> x.flatten('F')
array([1, 3, 2, 4])
>>> x.ravel('F')
array([1, 3, 2, 4])
 
>>> x.reshape(-1)
array([1, 2, 3, 4])
>>> x.T.reshape(-1)
array([1, 3, 2, 4])

>>> x = np.array([[1, 2], [3, 4]])
 
>>> x.flatten()[1] = 100  # flatten：返回的是拷贝
>>> x
array([[1, 2],
       [3, 4]])           
 
>>> x.ravel()[1] = 100
>>> x
array([[  1, 100],
       [  3,   4]])