Python Pandas - Append a collection of Index options together

To append a collection of Index options together, use the append() method in Pandas. This method combines multiple Index objects into a single Index without modifying the original indexes.

Creating Basic Pandas Index

First, let's create a basic Pandas Index ?

import pandas as pd

# Creating Pandas index
index1 = pd.Index([10, 20, 30, 40, 50])

# Display the Pandas index
print("Pandas Index...\n", index1)
print("\nNumber of elements in the index...\n", index1.size)

Pandas Index...
 Index([10, 20, 30, 40, 50], dtype='int64')

Number of elements in the index...
 5

Appending Single Index

Create a second index and append it to the first one ?

import pandas as pd

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

# Append the new index
result = index1.append(index2)
print("After appending...\n", result)

After appending...
 Index([10, 20, 30, 40, 50, 60, 70, 80], dtype='int64')

Appending Multiple Indexes

You can append multiple indexes at once by passing a list ?

import pandas as pd

index1 = pd.Index([10, 20, 30])
index2 = pd.Index([40, 50])
index3 = pd.Index([60, 70, 80])

# Append multiple indexes
result = index1.append([index2, index3])
print("After appending multiple indexes...\n", result)

After appending multiple indexes...
 Index([10, 20, 30, 40, 50, 60, 70, 80], dtype='int64')

Key Points

• The append() method returns a new Index object
• Original indexes remain unchanged
• You can append single or multiple indexes
• All indexes must have compatible data types

Conclusion

Use append() to combine multiple Pandas Index objects. The method preserves the original indexes and returns a new combined Index with all elements in order.