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This tutorial explains how to set and get the name of the index column in a Pandas DataFrame. We will use the following DataFrame example in the article.

import pandas as pd

my_df = pd.DataFrame(
    {
        "Applicant": ["Ratan", "Anil", "Mukesh", "Kamal"],
        "Hometown": ["Delhi", "Pune", "Dhangadi", "Kolkata"],
        "Score": [85, 87, 90, 89],
    },
    index=["2021-01-03", "2021-01-04", "2021-01-05", "2021-01-06"],
)

print(my_df)

Output:

           Applicant  Hometown  Score
2021-01-03     Ratan     Delhi     85
2021-01-04      Anil      Pune     87
2021-01-05    Mukesh  Dhangadi     90
2021-01-06     Kamal   Kolkata     89

Get the name of the index column in a DataFrame

We can nameget the name of the index column of a DataFrame through the index column's attribute.

import pandas as pd

my_df = pd.DataFrame(
    {
        "Applicant": ["Ratan", "Anil", "Mukesh", "Kamal"],
        "Hometown": ["Delhi", "Pune", "Dhangadi", "Kolkata"],
        "Score": [85, 87, 90, 89],
    },
    index=["2021-01-03", "2021-01-04", "2021-01-05", "2021-01-06"],
)

print("The DataFrame is:")
print(my_df, "\n")

print("Name of Index Column of the DataFrame is:")
print(my_df.index.name)

Output:

The DataFrame is:
           Applicant  Hometown  Score
2021-01-03     Ratan     Delhi     85
2021-01-04      Anil      Pune     87
2021-01-05    Mukesh  Dhangadi     90
2021-01-06     Kamal   Kolkata     89

Name of Index Column of the DataFrame is:
None

Since we did not my_dfset the name of the index column for the DataFrame, my_dfthe index column name of the DataFrame is obtained None.

nameYou can set the name of the index column of a DataFrame by setting the

We can set the name of the DataFrame's index column by simply setting the value indexof the DataFrame's index attribute .name

import pandas as pd

my_df = pd.DataFrame(
    {
        "Applicant": ["Ratan", "Anil", "Mukesh", "Kamal"],
        "Hometown": ["Delhi", "Pune", "Dhangadi", "Kolkata"],
        "Score": [85, 87, 90, 89],
    },
    index=["2021-01-03", "2021-01-04", "2021-01-05", "2021-01-06"],
)

print("Initial DataFrame:")
print(my_df, "\n")

my_df.index.name = "Date"

print("DataFrame after setting the name of Index Column:")
print(my_df, "\n")

print("Name of Index Column of the DataFrame is:")
print(my_df.index.name)

Output:

Initial DataFrame:
           Applicant  Hometown  Score
2021-01-03     Ratan     Delhi     85
2021-01-04      Anil      Pune     87
2021-01-05    Mukesh  Dhangadi     90
2021-01-06     Kamal   Kolkata     89

DataFrame after setting the name of Index Column:
           Applicant  Hometown  Score
Date
2021-01-03     Ratan     Delhi     85
2021-01-04      Anil      Pune     87
2021-01-05    Mukesh  Dhangadi     90
2021-01-06     Kamal   Kolkata     89

Name of Index Column of the DataFrame is:
Date

It sets the value of the property my_dfof .indexDate

Use rename_axis()the method to set the name of the index column of the DataFrame.

We can set the name of the index column rename_axis()in the DataFrame by passing the name of the index column as an argument to the method.

import pandas as pd

my_df = pd.DataFrame(
    {
        "Applicant": ["Ratan", "Anil", "Mukesh", "Kamal"],
        "Hometown": ["Delhi", "Pune", "Dhangadi", "Kolkata"],
        "Score": [85, 87, 90, 89],
    },
    index=["2021-01-03", "2021-01-04", "2021-01-05", "2021-01-06"],
)

print("Initial DataFrame:")
print(my_df, "\n")

my_df = my_df.rename_axis("Date")

print("DataFrame after setting the name of Index Column:")
print(my_df, "\n")

print("Name of Index Column of the DataFrame is:")
print(my_df.index.name)

Output:

Initial DataFrame:
           Applicant  Hometown  Score
2021-01-03     Ratan     Delhi     85
2021-01-04      Anil      Pune     87
2021-01-05    Mukesh  Dhangadi     90
2021-01-06     Kamal   Kolkata     89

DataFrame after setting the name of Index Column:
           Applicant  Hometown  Score
Date
2021-01-03     Ratan     Delhi     85
2021-01-04      Anil      Pune     87
2021-01-05    Mukesh  Dhangadi     90
2021-01-06     Kamal   Kolkata     89

Name of Index Column of the DataFrame is:
Date

It sets the column names of rename_axis()the DataFrame to using the method .my_dfindexDate