How do I use the apply function in pandas?

How do I use the apply function in pandas?

The apply function in pandas allows you to apply a function along an axis of a DataFrame or Series. Would you like an example?

Yes, please provide an example of using apply on a DataFrame.

Sure! Here's a simple example:

import pandas as pd

data = {'A': [1, 2, 3], 'B': [4, 5, 6]}
df = pd.DataFrame(data)

# Applying a function to column 'A'
df['A_squared'] = df['A'].apply(lambda x: x ** 2)
print(df)

This will create a new column 'A_squared' with the squares of the values in column 'A'.

What if I want to apply a function to multiple columns?

You can use the apply function with axis=1 to apply a function across rows. For example:

df['C'] = df.apply(lambda row: row['A'] + row['B'], axis=1)

This will create a new column 'C' that is the sum of columns 'A' and 'B'.