Python Pandas - Form the Union of two Index objects

To form the Union of two Index objects, use the index1.union(index2) method in Pandas. At first, import the required libraries −

import pandas as pd

Creating two Pandas index −

index1 = pd.Index([10, 20, 30, 40, 50])
index2 = pd.Index([80, 65, 60, 70, 55])

Display the Pandas index1 and index2 −

print("Pandas Index1...\n",index1)
print("Pandas Index2...\n",index2)

Perform union −

res = index1.union(index2)

Example

Following is the code −

import pandas as pd

# Creating two Pandas index
index1 = pd.Index([10, 20, 30, 40, 50])
index2 = pd.Index([80, 65, 60, 70, 55])

# Display the Pandas index1 and index2
print("Pandas Index1...\n",index1)
print("Pandas Index2...\n",index2)

# Return the number of elements in Index1 and Index2
print("\nNumber of elements in index1...\n",index1.size)
print("\nNumber of elements in index2...\n",index2.size)

# Perform union
res = index1.union(index2)

# Union of both the indexes
print("\nThe index1 and index2 Union...\n",res)

Output

This will produce the following output −

Pandas Index1...
Int64Index([10, 20, 30, 40, 50], dtype='int64')
Pandas Index2...
Int64Index([80, 65, 60, 70, 55], dtype='int64')

Number of elements in index1...
5

Number of elements in index2...
5

The index1 and index2 Union...
Int64Index([10, 20, 30, 40, 50, 55, 60, 65, 70, 80], dtype='int64')