Python math.log2() – Logarithm to Base 2

Python math.log2()

math.log2(x) function returns the logarithm of x to base 2.

Syntax

The syntax to call log2() function is

math.log2(x)

where

ParameterRequiredDescription
xYesA numeric value. The value must be greater than 0.

If x is an invalid value, such as a negative value, then log2() raises ValueError.

Examples

In the following program, we find the logarithm of 8 to base 2, using log2() function of math module.

Python Program

import math

x = 8
result = math.log2(x)
print('log2(x) :', result)

Output

log2(x) : 3.0

Logarithm of a negative number to base 2.

Python Program

import math

x = -1
result = math.log2(x)
print('log2(x) :', result)

Output

ValueError: math domain error

Logarithm of infinity.

Python Program

import math

x = math.inf
result = math.log2(x)
print('log2(x) :', result)

Output

log2(x) : inf

Logarithm of 1024 to base 2.

Python Program

import math

x = 1024
result = math.log2(x)
print('log2(x) :', result)

Output

log2(x) : 10.0

Summary

In this Python Examples tutorial, we learned the syntax of, and examples for math.log2() function.