Pandas DataFrame median() Method – Be on the Right Side of Change (original) (raw)
Preparation
Before any data manipulation can occur, two (2) new libraries will require installation.
- The Pandas library enables access to/from a DataFrame.
- The NumPy library supports multi-dimensional arrays and matrices in addition to a collection of mathematical functions.
To install these libraries, navigate to an IDE terminal. At the command prompt ($), execute the code below. For the terminal used in this example, the command prompt is a dollar sign ($). Your terminal prompt may be different.
$ pip install pandas
Hit the <Enter> key on the keyboard to start the installation process.
$ pip install numpy
Hit the <Enter> key on the keyboard to start the installation process.
If the installations were successful, a message displays in the terminal indicating the same.
Feel free to view the PyCharm installation guide for the required libraries.
Add the following code to the top of each code snippet. This snippet will allow the code in this article to run error-free.
import pandas as pd import numpy as np
The median() method calculates and returns the median of DataFrame/Series elements across a requested axis. In other words, the median determines the middle number(s) of the dataset.
To fully understand median from a mathematical point of view, watch this short tutorial:
The syntax for this method is as follows:
DataFrame.median(axis=None, skipna=None, level=None, numeric_only=None, **kwargs)
| Parameter | Description |
|---|---|
| axis | If zero (0) or index is selected, apply to each column. Default 0.If one (1) apply to each row. |
| skipna | If this parameter is True, any NaN/NULL value(s) ignored. If False, all value(s) included: valid or empty. If no value, then None is assumed. |
| level | Set the appropriate parameter if the DataFrame/Series is multi-level. If no value, then None is assumed. |
| numeric_only | Only include columns that contain integers, floats, or boolean values. |
| **kwargs | This is where you can add additional keywords. |
We will determine the median value(2) for our Hockey Teams for this example.
df_teams = pd.DataFrame({'Bruins': [4, 5, 9], 'Oilers': [3, 6, 14], 'Leafs': [2, 7, 11], 'Flames': [21, 8, 7]})
result = df_teams.median(axis=0) print(result)
- Line [1] creates a DataFrame from a dictionary of lists and saves it to
df_teams. - Line [2] uses the
median()method to calculate the median of the Teams. This output saves to theresultvariable. - Line [3] outputs the result to the terminal.
Output
| Bruins | 5.0 |
|---|---|
| Oilers | 6.0 |
| Leafs | 7.0 |
| Flames | 8.0 |
| dtype: | float64 |
More Pandas DataFrame Methods
Feel free to learn more about the previous and next pandas DataFrame methods (alphabetically) here:
Also, check out the full cheat sheet overview of all Pandas DataFrame methods.