numpy matrix operations | identity() function

numpy.matlib.identity() is another function for doing matrix operations in numpy. It returns a square identity matrix of given input size.

Syntax : numpy.matlib.identity(n, dtype=None)

Parameters :
n : [int] Number of rows and columns in the output matrix.
dtype : [optional] Desired output data-type.

Return : n x n matrix with its main diagonal set to one, and all other elements zero.

Code #1 :

# Python program explaining
# numpy.matlib.identity() function

# importing matrix library from numpy
import numpy as geek
import numpy.matlib

# desired 3 x 3 output square identity matrix
out_mat = geek.matlib.identity(3)
print ("Output matrix : ", out_mat)

Output :

Output matrix :  
[[ 1.  0.  0.]
 [ 0.  1.  0.]
 [ 0.  0.  1.]]

Code #2 :

# Python program explaining
# numpy.matlib.identity() function

# importing numpy and matrix library
import numpy as geek
import numpy.matlib

# desired 5 x 5 output square identity matrix
out_mat = geek.matlib.identity(n = 5, dtype = int)
print ("Output matrix : ", out_mat)

Output :

Output matrix :  
[[1 0 0 0 0]
 [0 1 0 0 0]
 [0 0 1 0 0]
 [0 0 0 1 0]
 [0 0 0 0 1]]