NumPy: Interchange two axes of an array

Last update on December 21 2024 07:38:38 (UTC/GMT +8 hours)

Change Two Array Axes

Write a NumPy program to change two array axes.

Pictorial Presentation:

Sample Solution:

Python Code:

# Importing the NumPy library with an alias 'np'
import numpy as np

# Creating a 2D NumPy array with one row and three columns
x = np.array([[1, 2, 3]])

# Printing the original array
print(x)

# Swapping the axes (dimensions) of the array using 'swapaxes' method
# Swapping axis 0 (rows) with axis 1 (columns)
y = np.swapaxes(x, 0, 1)

# Printing the array after swapping axes
print(y) 

Sample Output:

[[1 2 3]]                                                              
[[1]                                                                   
 [2]                                                                   
 [3]]

Explanation:

In the above code - x = np.array([[1,2,3]]): This line creates a 2D array x with the given list of lists. The array has a shape of (1, 3).

y = np.swapaxes(x,0,1): The np.swapaxes() function takes three arguments: the input array, and two axis numbers to be swapped. In this case, it swaps axis 0 (rows) with axis 1 (columns) of the array x. As a result, the shape of the new array y is (3, 1).

Python-Numpy Code Editor: