# Python math.isinf() – Check if Number is Infinity

Contents

## Python math.isinf()

math.isinf(x) function returns True if x is either positive infinity or negative infinity, and False otherwise.

## Syntax

The syntax to call isinf() function is

``math.isinf(x)``

where

## Examples

### 1. Check if positive infinity is infinity

Assign x with positive infinity, and programmatically check if x is infinity value, using math.isinf().

Python Program

``````import math

x = math.inf
result = math.isinf(x)
print('isinf(x) :', result)``````
Run Code Copy

Output

``isinf(x) : True``

### 2. Check if negative infinity is infinity

Assign x with negative infinity, and programmatically check if x is infinity value, using math.isinf().

Python Program

``````import math

x = -math.inf
result = math.isinf(x)
print('isinf(x) :', result)``````
Run Code Copy

Output

``isinf(x) : True``

### 3. Check if integer 8 is infinity

Assign x with a finite value, like 8, and programmatically check if x is infinity value, using math.isinf().

Python Program

``````import math

x = 8
result = math.isinf(x)
print('isinf(x) :', result)``````
Run Code Copy

Output

``isinf(x) : False``

## Summary

In this Python Math tutorial, we learned the syntax of, and examples for math.isinf() function.

## Related Tutorials

Code copied to clipboard successfully 👍