How to Merge Two Excel Columns in Pandas Using bfill and loc

Hello, I’m a Python enthusiast sharing a pandas data‑processing question from a community chat.

1. Introduction

A user asked how to merge two Excel columns so that empty cells are replaced by values from the other column.

2. Implementation

The instructor suggested using the pandas method .bfill(axis=1) to back‑fill missing values across columns.

Other participants mentioned that the task could be done in Excel with the CONCAT function, but pandas offers a more scalable solution.

One approach is to assign values directly to a column: df['column_name'] = 'value' For multiple columns, you can use df.loc[:, ['col1', 'col2', 'col3']] = ["value", 0, 0] to set values in one statement.

If warnings appear, they can be ignored with warnings.filterwarnings('ignore'), though converting warnings to exceptions is also possible.

3. Summary

The discussion provided concrete pandas techniques—bfill, direct assignment, and loc—to merge columns and handle missing data, helping the community solve the problem quickly and efficiently.