Python | numpy.fill_diagonal() method

With the help of numpy.fill_diagonal() method, we can get filled the diagonals of numpy array with the value passed as the parameter in numpy.fill_diagonal() method.

Syntax : numpy.fill_diagonal(array, value)
Return : Return the filled value in the diagonal of an array.

Example #1 :
In this example we can see that by using numpy.fill_diagonal() method, we are able to get the diagonals filled with the values passed as parameter.

# import numpy
import numpy as np

# using numpy.fill_diagonal() method
array = np.array([[1, 2], [2, 1]])
np.fill_diagonal(array, 5)

print(array)

Output :

[[5 2]
[2 5]]

Example #2 :

# import numpy
import numpy as np

# using numpy.fill_diagonal() method
array = np.zeros((3, 3), int)
np.fill_diagonal(array, 1)

print(array)

Output :

[[1 0 0]
[0 1 0]
[0 0 1]]