Python Pandas - Return Index with duplicate values removed except the first occurrence

To return Index with duplicate values removed except the first occurrence, use the index.drop_duplicates() method. Use the keep parameter with value first.

At first, import the required libraries −

import pandas as pd

Creating the index with some duplicates −

index = pd.Index(['Car','Bike','Airplane','Ship','Airplane'])

Display the index −

print("Pandas Index with duplicates...\n",index)

Return Index with duplicate values removed. The "keep" parameter with value "first" keeps the first occurrence for each set of duplicated entries −

index.drop_duplicates(keep='first')

Example

Following is the code −

import pandas as pd

# Creating the index with some duplicates
index = pd.Index(['Car','Bike','Airplane','Ship','Airplane'])

# Display the index
print("Pandas Index with duplicates...\n",index)

# Return the dtype of the data
print("\nThe dtype object...\n",index.dtype)

# get the bytes in the data
print("\nGet the bytes...\n",index.nbytes)

# get the dimensions of the data
print("\nGet the dimensions...\n",index.ndim)

# Return Index with duplicate values removed
# The "keep" parameter with value "first" keeps the first occurrence for each set of duplicated entries
print("\nIndex with duplicate values removed (keeping the first occurrence)...\n",index.drop_duplicates(keep='first'))

Output

This will produce the following code −

Pandas Index with duplicates...
Index(['Car', 'Bike', 'Airplane', 'Ship', 'Airplane'], dtype='object')

The dtype object...
object

Get the bytes...
40

Get the dimensions...
1

Index with duplicate values removed (keeping the first occurrence)...
Index(['Car', 'Bike', 'Airplane', 'Ship'], dtype='object')