Pandas - Apply a Lambda Function to Column Values with apply()

Last update on April 09 2025 12:53:13 (UTC/GMT +8 hours)

6. Apply Lambda Function to DataFrame Columns Using apply()

Write a Pandas program that apply a Lambda function to DataFrame columns using apply() function.

In this exercise, we have applied a lambda function that halves the values of a column using apply() function.

Sample Solution:

Code :

import pandas as pd

# Create a sample DataFrame
df = pd.DataFrame({
    'A': [10, 20, 30],
    'B': [40, 50, 60]
})

# Apply a lambda function to halve the values in column 'A'
df['A'] = df['A'].apply(lambda x: x / 2)

# Output the result
print(df)

Output:

      A   B
0   5.0  40
1  10.0  50
2  15.0  60                               

Explanation:

• Created a DataFrame with columns 'A' and 'B'.
• Applied a lambda function to divide the values in column 'A' by 2.
• Modified column 'A' and printed the updated DataFrame.

For more Practice: Solve these Related Problems:

• Write a Pandas program to apply a lambda function on a column that calculates the percentage change from the previous row using apply().
• Write a Pandas program to use apply() with a lambda function to convert temperature values from Celsius to Fahrenheit in a DataFrame column.
• Write a Pandas program to apply a lambda function to each column that rounds numeric values to the nearest integer using apply().
• Write a Pandas program to use apply() with a lambda function to flag values above a threshold in a DataFrame column.

Python-Pandas Code Editor:

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