Deleting a Column from a Pandas DataFrame
While using the del keyword on the DataFrame itself (del df.column_name) may seem intuitive, it is not the recommended method for deleting columns in Pandas. Unexpected errors can arise because the del keyword removes the entire column from the DataFrame object, not just its values.
Preferred Approach: Using the drop() Method
The proper way to remove a column from a DataFrame is through the drop() method. It allows for precise targeting and control over the deletion process. The general syntax is:
df = df.drop('column_name', axis=1)
where 1 represents the axis number for columns (0 is for rows). This approach ensures that only the specified column is deleted, leaving the remaining data intact.
Alternative Syntax: Using the columns Keyword
An alternative syntax for drop() is to use the columns keyword:
df = df.drop(columns=['column_nameA', 'column_nameB'])
This method is particularly useful when deleting multiple columns.
In-place Modification
If you wish to modify the original DataFrame inplace without reassignment, use:
df.drop('column_name', axis=1, inplace=True)
Dropping by Column Number
To delete columns by their position (number) instead of label, use:
df = df.drop(df.columns[[0, 1, 3]], axis=1) # df.columns is zero-based pd.Index
Using Text Syntax
Similar to the columns keyword, you can also use text syntax to specify the columns to be dropped:
df.drop(['column_nameA', 'column_nameB'], axis=1, inplace=True)
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