Python Numpy transpose() Function

1. Syntax of numpy.transpose():
2. Example Codes: numpy.transpose() Method
3. Example Codes: Set axes Parameter in numpy.transpose() Method

Python Numpy numpy.transpose() reverses the axes of the input array or simply transposes the input array.

Syntax of numpy.transpose():

numpy.transpose(ar, axes=None)

Parameters

Return

It returns transpose of the input array if it is a 2-D, however, the input array remains unchanged if it is 1-D.

Example Codes: numpy.transpose() Method

import numpy as np

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

print("Matrix x:")
print(x)

x_transpose=np.transpose(x)
print("\nTranspose of Matrix x:")
print(x_transpose)

Output:

Matrix x:
[[2 3 3]
 [3 2 1]]

Transpose of Matrix x:
[[2 3]
 [3 2]
 [3 1]]

It returns the transposed version of the input array x. The rows of matrix x become columns of matrix x_transpose and columns of matrix x become rows of matrix x_transpose.

However, if we pass a 1-D array in the numpy.transpose() method, there is no change in the returned array.

import numpy as np

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

print("Matrix x:")
print(x)

x_transpose=np.transpose(x)
print("\nTranspose of Matrix x:")
print(x_transpose)

Output:

Matrix x:
[2 3 3]

Transpose of Matrix x:
[2 3 3]

It shows 1-D array remains unchanged after passing through the np.transpose() method.

Example Codes: Set axes Parameter in numpy.transpose() Method

import numpy as np

x = np.random.random((1, 2, 3, 5))

print("Shape of x:")
print(x.shape)

x_permuted=np.transpose(x, (3, 0, 2,1))

print("\nShape of x_permuted:")
print(x_permuted.shape)

Output:

Shape of x:
(1, 2, 3, 5)

Shape of x_permuted:
(5, 1, 3, 2)

Here, axes is passed as second parameter to the numpy.transpose() method.

The ith axis of the returned array will be axes[i]-th axis of the input array.

Hence 0th axis in the above example of x becomes the first axis of x_permuted.