Applying a Lambda Function to a Series using map() in Pandas

Last update on April 09 2025 12:53:08 (UTC/GMT +8 hours)

15. Use map() with Lambda for Custom Function

Write a Pandas program that uses map() function to apply a custom function with a Lambda.

In this exercise, we have used map() function with a lambda expression to apply a simple mathematical operation on a Series.

Sample Solution :

Code :

import pandas as pd

# Create a sample Series
s = pd.Series([1, 2, 3, 4, 5])

# Apply a lambda function to multiply each element by 3 using map()
s_multiplied = s.map(lambda x: x * 3)

# Output the result
print(s_multiplied)

Output:

0     3
1     6
2     9
3    12
4    15
dtype: int64                                   

Explanation:

• Created a Pandas Series with five elements.
• Used a lambda function to multiply each element by 3.
• Applied the lambda function to the Series using map().
• Outputted the resulting Series, where all values have been multiplied by 3.

For more Practice: Solve these Related Problems:

• Write a Pandas program to use the map() function with a lambda to convert numerical codes in a Series to descriptive labels.
• Write a Pandas program to apply a lambda function via map() that adds a prefix to each string in a Series.
• Write a Pandas program to use map() with a lambda to transform a Series of dates from string to datetime format.
• Write a Pandas program to use map() to apply a lambda function that computes the square of each number in a numeric Series.

Python-Pandas Code Editor:

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