Pandas DataFrame apply() Method

Example

Return the sum of each row by applying a function:

import pandas as pd

def calc_sum(x):
return x.sum()

data = {
"x": [50, 40, 30],
"y": [300, 1112, 42]
}

df = pd.DataFrame(data)

x = df.apply(calc_sum)

print(x)

Try it Yourself »

Definition and Usage

The apply() method allows you to apply a function along one of the axis of the DataFrame, default 0, which is the index (row) axis.

Syntax

dataframe.apply(func, axis, raw, result_type, args, kwds)

Parameters

The axis, raw, result_type, and args parameters are keyword arguments.

Parameter	Value	Description
func		Required. A function to apply to the DataFrame.
axis	`0 1 'index' 'columns'`	Optional, Which axis to apply the function to. default 0.
raw	`True False`	Optional, default False. Set to true if the row/column should be passed as an ndarray object
result_type	`'expand' 'reduce' 'broadcast' None`	Optional, default None. Specifies how the result will be returned
args	a tuple	Optional, arguments to send into the function
kwds	keyword arguments	Optional, keyword arguments to send into the function

Return Value

A DataFrame or a Series object, with the changes.

This function does NOT make changes to the original DataFrame object.

❮ DataFrame Reference