Add Prefix to Column Labels of DataFrame in Pandas

Add Prefix to Column Labels of DataFrame

To add a string before each column label of DataFrame in Pandas, call add_prefix() method on this DataFrame, and pass the prefix string as argument to add_prefix() method.

In this tutorial, we will learn how to add a string as prefix to column labels of DataFrame, with examples.

Syntax

The syntax of pandas DataFrame.add_prefix() method is

DataFrame.add_prefix(prefix)

where

Parameter	Value	Description
prefix	str	The string to add before each label.

Return Value

DataFrame with updated column labels.

Examples

In the following program, we will take a DataFrame with column labels [‘1’, ‘2’]. We add prefix string ‘col_’ to the column labels of this DataFrame using DataFrame.add_prefix() method.

Example.py

import pandas as pd

df = pd.DataFrame(
    {'1': [10, 20, 30], '2': [40, 50, 60]})

prefix = 'col_'

result = df.add_prefix(prefix)
print(result)

Output

   col_0  col_1
0     10     40
1     20     50
2     30     60

Now, let us try with the prefix string ‘x_’.

Example.py

import pandas as pd

df = pd.DataFrame(
    {'1': [10, 20, 30], '2': [40, 50, 60]})

prefix = 'x_'

result = df.add_prefix(prefix)
print(result)

Output

   x_1  x_2
0   10   40
1   20   50
2   30   60

Conclusion

In this Pandas Tutorial, we learned how to add a string as prefix to column labels of DataFrame, using pandas DataFrame.add_prefix() method.