Pandas - Conditional Selection with MultiIndex

Last update on April 09 2025 12:51:32 (UTC/GMT +8 hours)

15. MultiIndex Conditional Data Selection

Write a Pandas program that uses MultiIndex to select data based on conditions.

Sample Solution :

Python Code :

import pandas as pd

# Create a DataFrame
df = pd.DataFrame({
    'X': [1, 6, 8, 3, 7],
    'Y': [5, 2, 9, 4, 1],
    'Z': ['one', 'one', 'two', 'two', 'one']
})

# Set MultiIndex
df = df.set_index(['Z', 'X'])

# Conditional selection with MultiIndex
result = df.loc[('one', slice(None))]
print(result)

Output:

    Y
X   
1  5
6  2
7  1

Explanation:

• Import pandas library.
• Create a DataFrame.
• Set a MultiIndex using columns 'Z' and 'X'.
• Use .loc with a slice to select data for MultiIndex 'one'.
• Print the results.

For more Practice: Solve these Related Problems:

• Write a Pandas program to create a MultiIndex DataFrame and then use conditional selection to filter data based on level values.
• Write a Pandas program to apply boolean conditions on a MultiIndex DataFrame and return rows that meet specific criteria.
• Write a Pandas program to select data from a MultiIndex DataFrame using a combination of index levels and column conditions.
• Write a Pandas program to create a MultiIndex DataFrame, apply a custom filter to each level, and display the filtered result.

Python-Pandas Code Editor:

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