Python math.isnan()
In Python, the math.isnan() function returns True if the given value is NaN (not a number) and False if the value is a number.
This method belongs to the group of number-theoretic and representation functions in the math module and is used to handle simple (not complex) numbers. Except when explicitly noted otherwise, this function expects a float-type numeric value.
Syntax
math.isnan(x)
x: The numeric value to be checked.
Example 1
In the example below, math.isnan() returns False because the variable num is a valid numeric value, not NaN:
import mathnum = 20print(math.isnan(num))
The example above results in the following output:
False
Example 2
In the example below, math.isnan() returns True because the variable nan, created using float, represents a “Not a Number” (NaN) value:
import mathnan = float('nan')print(math.isnan(nan))
The example above results in the following output:
True
Codebyte Example
Run the following code to understand how the math.isnan() method works:
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