How to calculate median in Pandas

Here’s how to calculate median in Pandas.
how to calculate median in Pandas

To calculate the median in Pandas use the median function.

Median of a single column

import pandas as pd

df1 = pd.DataFrame({"my_column1": ['9', '2', '3', '5'],
                    "my_column2": ['3', '7', '6', '4'],
                    "my_column3": ['4', '8', '8', '8']})

median = df1['my_column2'].median()

print(f'The median of my_column2 is equal to: {median}')

The result looks like this.

Median of my_column2 equals: 5.0

To calculate the median of multiple columns in Pandas, use the median function.

Median of many columns

import pandas as pd

df1 = pd.DataFrame({"my_column1": ['9', '2', '3', '5'],
                    "my_column2": ['3', '7', '6', '4'],
                    "my_column3": ['4', '8', '8', '8']})

median = df1[['my_column2', 'my_column3']].median()

print(f'The median of my columns is equal to:\n{median}')

The result looks like this.

The median of my columns is equal to:
my_column2    5.0
my_column3    8.0
dtype: float64

Remember to enter two pairs of square brackets. If you forget, you will get the following error:

Traceback (most recent call last):
  File "C:\Users\pandashowto\PycharmProjects\venv\lib\site-packages\pandas\core\indexes\base.py", line 3361, in get_loc
    return self._engine.get_loc(casted_key)
  File "pandas\_libs\index.pyx", line 76, in pandas._libs.index.IndexEngine.get_loc
  File "pandas\_libs\index.pyx", line 108, in pandas._libs.index.IndexEngine.get_loc
  File "pandas\_libs\hashtable_class_helper.pxi", line 5198, in pandas._libs.hashtable.PyObjectHashTable.get_item
  File "pandas\_libs\hashtable_class_helper.pxi", line 5206, in pandas._libs.hashtable.PyObjectHashTable.get_item
KeyError: ('my_column2', 'my_column3')

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "C:\Users\pandashowto\PycharmProjects\new.py", line 7, in 
    median = df1['my_column2', 'my_column3'].median()
  File "C:\Users\pandashowto\PycharmProjects\venv\lib\site-packages\pandas\core\frame.py", line 3455, in __getitem__
    indexer = self.columns.get_loc(key)
  File "C:\Users\pandashowto\PycharmProjects\venv\lib\site-packages\pandas\core\indexes\base.py", line 3363, in get_loc
    raise KeyError(key) from err
KeyError: ('my_column2', 'my_column3')

Process finished with exit code 1

Median of all columns

You can also calculate the median of your entire dataframe. If you use the median method directly, you get the median of all columns.

import pandas as pd

df1 = pd.DataFrame({"my_column1": ['9', '2', '3', '5'],
                    "my_column2": ['3', '7', '6', '4'],
                    "my_column3": ['4', '8', '8', '8']})

print(f'The median of columns:\n{df1.median()}')

The result looks like this.

The median of columns:
my_column1    4.0
my_column2    5.0
my_column3    8.0
dtype: float64

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