log2() logarithm of a positive integer with base 2 in Python

log2(x) returns logarithm of x with base 2

import math
print(math.log2(2))  # 1.0
print(math.log2(4))  # 2.0
print(math.log2(5))  # 2.321928094887362

Using negative number
For any value less than or equal to 0 , we will get ValueError

import math
print(math.log2(-2))

Above code will generate error.

Use Case: Data Size Calculation: To calculate how many bits are needed to store a number:

print(math.log2(1024) + 1)  # Output: 11.0

Example 2: Error Handling for Negative Numbers

The `log2()` function raises a ValueError if `x` is 0 or negative, as log values are undefined for such inputs.

import math
try:
    print(math.log2(-4))
except ValueError as e:
    print("Error:", e)

Output

Error: math domain error

In binary trees, the depth (number of levels) for a full tree can be calculated using `log2()`.

import math
nodes = 8
depth = math.log2(nodes + 1)
print("Tree depth:", int(depth))

Output

Tree depth: 3

Computer Science: To calculate data storage sizes, binary tree depths, and algorithm complexity.
Information Theory: To determine entropy and information content.
Signal Processing: Logarithmic scaling of binary data for processing.