Python将一个2D的numpy数组扁平化为1D数组

给定一个2d numpy数组，任务是将2d numpy数组平移为1d数组。下面是解决这个任务的几种方法。

方法#1：使用np.flatten()

# Python code to demonstrate
# flattening a 2d numpy array
# into 1d array
  
import numpy as np
  
ini_array1 = np.array([[1, 2, 3], [2, 4, 5], [1, 2, 3]])
  
# printing initial arrays
print("initial array", str(ini_array1))
  
# Multiplying arrays
result = ini_array1.flatten()
  
# printing result
print("New resulting array: ", result)

输出:

initial array [[1 2 3]
 [2 4 5]
 [1 2 3]]
New resulting array:  [1 2 3 2 4 5 1 2 3]

方法二：使用np.ravel()

# Python code to demonstrate
# flattening a 2d numpy array
# into 1d array
  
import numpy as np
  
ini_array1 = np.array([[1, 2, 3], [2, 4, 5], [1, 2, 3]])
  
# printing initial arrays
print("initial array", str(ini_array1))
  
# Multiplying arrays
result = ini_array1.ravel()
  
# printing result
print("New resulting array: ", result)

输出:

initial array [[1 2 3]
 [2 4 5]
 [1 2 3]]
New resulting array:  [1 2 3 2 4 5 1 2 3]

方法#3：使用np.reshape()

# Python code to demonstrate
# flattening a 2d numpy array
# into 1d array
  
import numpy as np
  
ini_array1 = np.array([[1, 2, 3], [2, 4, 5], [1, 2, 3]])
  
# printing initial arrays
print("initial array", str(ini_array1))
  
# Multiplying arrays
result = ini_array1.reshape([1, 9])
  
# printing result
print("New resulting array: ", result)

输出:

initial array [[1 2 3]
 [2 4 5]
 [1 2 3]]
New resulting array:  [[1 2 3 2 4 5 1 2 3]]