Grouping DataFrame by column and calculating mean in Python

Python Pandas Numpy: Exercise-13 with Solution

Group a Pandas DataFrame by a column and calculate the mean of another column.

Sample Solution:

Python Code:

import pandas as pd

# Create a sample DataFrame
data = {'Category': ['A', 'B', 'A', 'B', 'A', 'B'],
        'Values': [100, 200, 300, 400, 500, 600]}

df = pd.DataFrame(data)

# Group by 'Category' and calculate the mean of 'Values'
mean_values = df.groupby('Category')['Values'].mean()

# Display the mean values


A    300.0
B    400.0
Name: Values, dtype: float64


In the exerciser above -

  • First we create a sample DataFrame (df) with columns 'Category' and 'Values'.
  • The groupby('Category') method groups the DataFrame by the 'Category' column.
  • The ['Values'].mean() part calculates the mean of the 'Values' column for each group.
  • The result is a Pandas Series with the mean values for each category.


Flowchart: Grouping DataFrame by column and calculating mean in Python.

Python Code Editor:

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