NumPy Tutorial

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Misc

Numpy Attributes

numpy.identity() in Python

numpy.identity() in Python

The identity() method of Python numpy class returns an identity matrix i.e., a square matrix with ones on the main diagonal.

Syntax

numpy.identity(n, dtype=None)

Parameters

The numpy. identity()  method consists of two parameters, which are as follows:

N : It represents the number of rows(or columns).

dtype : It is an optional parameter. It depicts the data type of returned array, and by default, it is a float.

Return Value

The numpy.identity () method returns identity array of dimension n x n,  with its main diagonal set to one, and all other elements equal to zero.

Example 1

# Python Programming giving an example for
# numpy.identity() method
import numpy as numpy
# 2x2 matrix with 1's on main diagnol
obj1 = numpy.identity(3, dtype = float)
print("Matrix : \n", obj1)
obj2 = numpy.identity(4)
print("\nMatrix : \n", obj2)

Output

Matrix :
[[ 1.  0.  0.]
[ 0.  1.  0.]
[ 0.  0.  1.]]
Matrix :
[[ 1.  0.  0.  0.]
[ 0.  1.  0.  0.]
[ 0.  0.  1.  0.]
[ 0.  0.  0.  1.]]