Checking for NaN (Not a Number)

In Python, NaN (not a number) is represented by float('nan'). It's used to represent values that cannot be represented as real numbers. To check if a value is NaN, utilize the math.isnan function.

Example:

import math

x = float('nan')
if math.isnan(x):
    print("x is NaN")
else:
    print("x is not NaN")

Output:

x is NaN