find nan in df code example

Example 1: knowing the sum of null value is pandas dataframe

note:df is your pandas dataframe

print(df.isnull().sum())

Example 2: find nan value in dataframe python

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

Example 3: to detect if a data frame has nan values

df.isnull().sum().sum()
5