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Pandas DataFrame - median() function



The Pandas DataFrame median() function returns the median of the values over the specified axis. The syntax for using this function is mentioned below:

Syntax

DataFrame.median(axis=None, skipna=None, 
                 level=None, numeric_only=None)

Parameters

axis Optional. Specify {0 or 'index', 1 or 'columns'}. If 0 or 'index', median of the values are generated for each column. If 1 or 'columns', median of the values are generated for each row. Default: 0
skipna Optional. Specify True to exclude NA/null values when computing the result. Default is True.
level Optional. Specify level (int or str). If the axis is a MultiIndex (hierarchical), count along a particular level, collapsing into a Series. A str specifies the level name.
numeric_only Optional. Specify True to include only float, int or boolean data. Default: False

Return Value

Returns median of the values of Series or DataFrame if a level is specified.

Example: using median() column-wise on whole DataFrame

In the example below, a DataFrame df is created. The median() function is used to get the median of values for each column.

import pandas as pd
import numpy as np

df = pd.DataFrame({
  "Bonus": [5, 3, 2, 4],
  "Salary": [60, 62, 65, 59]},
  index= ["John", "Marry", "Sam", "Jo"]
)

print("The DataFrame is:")
print(df)

#median of values of all entries column-wise
print("\ndf.median() returns:")
print(df.median())

The output of the above code will be:

The DataFrame is:
       Bonus  Salary
John       5      60
Marry      3      62
Sam        2      65
Jo         4      59

df.median() returns:
Bonus      3.5
Salary    61.0
dtype: float64

Example: using median() row-wise on whole DataFrame

To perform the operation row-wise, the axis parameter can be set to 1.

import pandas as pd
import numpy as np

df = pd.DataFrame({
  "Bonus": [5, 3, 2, 4],
  "Salary": [60, 62, 65, 59]},
  index= ["John", "Marry", "Sam", "Jo"]
)

print("The DataFrame is:")
print(df)

#median of values of all entries row-wise
print("\ndf.median(axis=1) returns:")
print(df.median(axis=1))

The output of the above code will be:

The DataFrame is:
       Bonus  Salary
John       5      60
Marry      3      62
Sam        2      65
Jo         4      59

df.median(axis=1) returns:
John     32.5
Marry    32.5
Sam      33.5
Jo       31.5
dtype: float64

Example: using median() on selected column

Instead of whole DataFrame, the median() function can be applied on selected columns. Consider the following example.

import pandas as pd
import numpy as np

df = pd.DataFrame({
  "Bonus": [5, 3, 2, 4],
  "Last Salary": [58, 60, 63, 57],
  "Salary": [60, 62, 65, 59]},
  index= ["John", "Marry", "Sam", "Jo"]
)

print("The DataFrame is:")
print(df)

#median of values of single column
print("\ndf['Salary'].median() returns:")
print(df["Salary"].median())

#median of values of multiple columns
print("\ndf[['Salary', 'Bonus']].median() returns:")
print(df[["Salary", "Bonus"]].median())

The output of the above code will be:

The DataFrame is:
       Bonus  Last Salary  Salary
John       5           58      60
Marry      3           60      62
Sam        2           63      65
Jo         4           57      59

df['Salary'].median() returns:
61.0

df[['Salary', 'Bonus']].median() returns:
Salary    61.0
Bonus      3.5
dtype: float64

❮ Pandas DataFrame - Functions

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