numpy.identity() in Python

Last Updated : 22 Apr, 2025

numpy.identity() function is used to create an identity matrix which is used to make identity matrix. This is commonly used in linear algebra and numerical computations. It has the following properties:

Diagonal elements are all 1s.
Non-diagonal elements are all 0s.

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

where:

n : It takes int value and is Dimension n x n of output array
dtype : It returns Data type of returned array. It is optional and by default it is float.

In the below example we use numpy.identity() to create identity matrices of size 2×2 and 4×4 with 1s on the diagonal and 0s elsewhere. The dtype=float specifies that the matrix elements should be float type.

Python

import numpy as geek  b = geek.identity(2, dtype = float) print("Matrix b : \n", b)  a = geek.identity(4) print("\nMatrix a : \n", a)

Output :

Identity Matrix

It is useful for linear algebra operations like matrix multiplication, transformations and solving equations.

numpy.alen() in Python

Mohit Gupta_OMG

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