nan in python pandas code example

Example 1: find nan value in dataframe python

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

Example 2: pandas where retuning NaN

# Try using a loc instead of a where:
df_sub = df.loc[df.yourcolumn == 'yourvalue']

Example 3: represent NaN with pandas in python

import pandas as pd

if pd.isnull(float("Nan")):
  print("Null Value.")