drop missing data in dataframe

1. null or NaN or missing data check

   df.isnull().sum()

 

2. drop data based on X-axis

   df.dropna(axis=0)

 

3. drop data in terms of Y-axis

   df.dropna(axis=1)

 

4. drop data included all NaN in Columns

   df.dropna(how='all')

 

5. drop rows that have fewer than 4 values

   df.dropna(thresh=4)

 

6. drop data in specific columns

   df.dropna(subset=['C'])