How to Flatten a Hierarchical Column Index in a Pandas DataFrame?

How to Flatten a Hierarchical Index in Columns

Problem:

You have a DataFrame with a hierarchical index in columns and want to flatten it into a single level.

Answer:

The most straightforward approach is to set the columns to the top level of the hierarchy using the following code:

df.columns = df.columns.get_level_values(0)

Alternative Approach:

If you want to combine the MultiIndex entries into a single Index, you can use the following code for columns with string entries:

df.columns = [' '.join(col).strip() for col in df.columns.values]

Explanation:

This code loops over the MultiIndex entries, joining the entries in each level with a space and then removing any leading or trailing whitespace. The resulting list of strings is assigned to the DataFrame's columns, creating a flattened index.

The above is the detailed content of How to Flatten a Hierarchical Column Index in a Pandas DataFrame?. For more information, please follow other related articles on the PHP Chinese website!