Add zero columns to Pandas Dataframe

Last Updated : 11 Dec, 2020

Prerequisites: Pandas

The task here is to generate a Python program using its Pandas module that can add a column with all entries as zero to an existing dataframe.

A Dataframe is a two-dimensional, size-mutable, potentially heterogeneous tabular data.It is used to represent data in tabular form like an Excel file format. Below is the syntax for creating a dataframe in pandas. It can be imagines as a dictionary like container for series object.

Syntax:

DataFrame(data=None, index=None, columns=None, dtype=None, copy=False)

Approach

Import required libraries
Create or import data
Add a new column with all zeroes.

Example 1:

Python3

# import pandas library
import pandas as pd

# creating dictionary of lists
dict = {'name': ["sohom", "rakesh", "rajshekhar", "sumit"],
        'department': ["ECE", "CSE", "EE", "MCA"],
        'CGPA': [9.2, 8.7, 8.6, 7.7]}

# creating a dataframe
df = pd.DataFrame(dict)

print("data frame before adding the column:")
display(df)

# creating a new column
# of zeroes to the
# dataframe
df['new'] = 0

# showing the dataframe
print("data frame after adding the column:")
display(df)

Output:

Example 2:

Python3

# import pandas library
import pandas as pd

# create data
data = [["geeks", 1], ["for", 2], ["best", 3]]

# creating a dataframe
df = pd.DataFrame(data, columns=['col1', 'col2'])

print("data frame before adding the column:")
display(df)

# creating a new column with all zero entries
df['col3'] = 0

# showing the dataframe
print("data frame after adding the column:")
display(df)