Missing Data
fillna — fill missing values
Replace null / NaN values with a constant.
Fill all columns
Fill specific columns
Use an indented block to fill different columns with different values:
Or use comma-separated syntax:
Only the listed columns are filled. All other columns are unchanged.
dropna — drop rows with missing values
Drop rows with any missing value
Drop rows where specific columns are missing
Only drop a row if any of the listed columns are null: