The .mean() method produces a new Series or DataFrame with aggregate mean values for the groups in a GroupBy object.



numeric_only is a boolean value. True includes only int, float, and boolean columns. It defaults to True.


The following example produces a GroupBy object from a DataFrame and executes the .mean() method on it.

import pandas as pd
df = pd.DataFrame({'Key' : ['A', 'A', 'A', 'B', 'B', 'C'],
'Value' : [15., 23., 17., 5., 8., 12.]})
print(df, end='\n\n')
group = df.groupby(['Key'], as_index=False)

This example produces the following output:

Key Value
0 A 15.0
1 A 23.0
2 A 17.0
3 B 5.0
4 B 8.0
5 C 12.0
Key Value
0 A 18.333333
1 B 6.500000
2 C 12.000000


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