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Python - Pandas replace a character in all column names

Given a Pandas DataFrame, we have to replace a character in all column names.
Submitted by Pranit Sharma, on July 30, 2022

Pandas is a special tool that allows us to perform complex manipulations of data effectively and efficiently. Inside pandas, we mostly deal with a dataset in the form of DataFrame. DataFrames are 2-dimensional data structures in pandas. DataFrames consist of rows, columns, and data.

Columns are the different fields that contain their particular values when we create a DataFrame. We can perform certain operations on both rows & column values. Headers are the values assigned to each column, it is an array of values and it acts as a row or headers.

Problem statement

Suppose we have three columns in our dataframe named '(A)','(B)' and '(C)' and we need to replace the opening and close parenthesis with _.

Replace a character in all column names

To replace a character in all column names in pandas DataFrame, you can use the df.columns.str.replace() method by specifying the old and new character to be replaced as the parameters of the function. Consider the below-given code snippets:

df.columns.str.replace("[()]", "_")

Let us understand with the help of an example,

Python program to replace a character in all column names

# Importing pandas package
import pandas as pd

# Creating a dictionary
d = {
    '(A)':[1,2,3,4],
    '(B)':['A','B','C','D'],
    '(C)':[True,False,True,False],
    '(D)':[1.223,3.224,5.443,6.534]
}

# Creating a dataframe
df = pd.DataFrame(d)

# Display Dataframe
print("DataFrame :\n",df,"\n")

# Replacing the character in column headers
df.columns = df.columns.str.replace("[()]", "_")

# Display modified DataFrame
print("Modified DataFrame:\n",df)

Output

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