check null or nan value python code example

Example 1: find nan value in dataframe python

# to mark NaN column as True
df['your column name'].isnull()

Example 2: check if something is nan python

import math
print math.isnan(float('NaN'))OutputTrue
print math.isnan(1.0)OutputFalse

Example 3: check if value is NaN

Number.isNaN(123)