How to Get the index column name in Pandas?

In this article, we will discuss multiple scenarios to get the index column name in pandas DataFrame.

Table of Contents

Preparing Dataset for solution

To quickly get started, let’s create a sample dataframe to experiment. We’ll use the pandas library with some random data.

import pandas as pd
import numpy as np

# List of Tuples
employees= [('Shubham', 'Data Scientist', 'Tech',   5),
            ('Riti', 'Data Engineer', 'Tech' ,   7),
            ('Shanky', 'Program Manager', 'PMO' ,   2),
            ('Shreya', 'Graphic Designer', 'Design' ,   2),
            ('Aadi', 'Backend Developer', 'Tech', 11),
            ('Sim', 'Data Engineer', 'Tech', 4)]

# Create a DataFrame object from list of tuples
df = pd.DataFrame(employees,
                  columns=['Name', 'Designation', 'Team', 'Experience'],
                 index = pd.Series([0, 1, 2, 3, 4, 5], name='Sr_no'))

print(df)

Contents of the created dataframe are,

          Name        Designation    Team  Experience
Sr_no                                                
0      Shubham     Data Scientist    Tech           5
1         Riti      Data Engineer    Tech           7
2       Shanky    Program Manager     PMO           2
3       Shreya   Graphic Designer  Design           2
4         Aadi  Backend Developer    Tech          11
5          Sim      Data Engineer    Tech           4

As observed, the index column name is set as “Sr_no”. Let’s explore how to get this value using multiple methods.

Get Index Column name in DataFrame

Every DataFrame has an index property that can be used to get/set the index details of the DataFrame. To get the index name, we can use the “name” attribute from the index property. Let’s try to code it below.

# getting column name of index
print (df.index.name)

Output

Sr_no

Pretty simple, right? We can extract other properties of the index as well using this.

Get index name in MultiIndex DataFrame

Getting the column name of the index in a multi-index DataFrame is slightly different. To understand, let’s first change our existing DataFrame by making both “Name” and “Designation” the DataFrame indexes.

# making the DataFrame multi-index
df.set_index(['Name', 'Designation'], inplace=True)

print (df)

Output

                             Team  Experience
Name    Designation                          
Shubham Data Scientist       Tech           5
Riti    Data Engineer        Tech           7
Shanky  Program Manager       PMO           2
Shreya  Graphic Designer   Design           2
Aadi    Backend Developer    Tech          11
Sim     Data Engineer        Tech           4

As observed, we have multi-index with column names as “Name” and “Designation”. Let’s try to run the above code to extract the index column names.

# getting column name of index
print (df.index.name)

Output

None

Much to our surprise, here the output is blank! For the multi-index DataFrames, we slightly need to tweak and use “names” as the attribute to get the list of column names.

# getting column name of index
print (df.index.names)

Output

FrozenList(['Name', 'Designation'])

The output here is a FrozenList, which can be easily created to a list or set by using the list function.

The complete example is as follows,

import pandas as pd
import numpy as np

# List of Tuples
employees= [('Shubham', 'Data Scientist', 'Tech',   5),
            ('Riti', 'Data Engineer', 'Tech' ,   7),
            ('Shanky', 'Program Manager', 'PMO' ,   2),
            ('Shreya', 'Graphic Designer', 'Design' ,   2),
            ('Aadi', 'Backend Developer', 'Tech', 11),
            ('Sim', 'Data Engineer', 'Tech', 4)]

# Create a DataFrame object from list of tuples
df = pd.DataFrame(employees,
                  columns=['Name', 'Designation', 'Team', 'Experience'],
                 index = pd.Series([0, 1, 2, 3, 4, 5], name='Sr_no'))

print(df)

# getting column name of index
print (df.index.name)

# making the DataFrame multi-index
df.set_index(['Name', 'Designation'], inplace=True)

print (df)

# getting column name of index
print (df.index.name)

# getting column name of index
print (df.index.names)

Output:

          Name        Designation    Team  Experience
Sr_no                                                
0      Shubham     Data Scientist    Tech           5
1         Riti      Data Engineer    Tech           7
2       Shanky    Program Manager     PMO           2
3       Shreya   Graphic Designer  Design           2
4         Aadi  Backend Developer    Tech          11
5          Sim      Data Engineer    Tech           4

Sr_no

                             Team  Experience
Name    Designation                          
Shubham Data Scientist       Tech           5
Riti    Data Engineer        Tech           7
Shanky  Program Manager       PMO           2
Shreya  Graphic Designer   Design           2
Aadi    Backend Developer    Tech          11
Sim     Data Engineer        Tech           4

None

['Name', 'Designation']

Summary

In this article, we have discussed multiple scenarios to get the index column name in pandas DataFrame. Thanks.