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Pandas DataFrame combine_first() Method

❮ DataFrame Reference


Example

Combine two DataFrames and use data from the second DataFrame if the first has a NULL value:

import pandas as pd

df1 = pd.DataFrame([[1, 2], [None, 4]])
df2 = pd.DataFrame([[5, 6], [7, 8]])

print(df1.combine_first(df2))
Try it Yourself »

Definition and Usage

The combine_first() method combines two DataFrame objects, and uses a the value from the second DataFrame if the first has a NULL value.


Syntax

dataframe.combine_first(other)

Parameters

Parameter Description
other Required. A DataFrame.

Return Value

A DataFrame object.


❮ DataFrame Reference

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