# stdev & pstdev Functions of statistics Module in Python (2 Examples)

In this tutorial, I’ll show how to **apply the stdev and pstdev functions** in the Python programming language.

Table of contents:

Let’s take a look at some Python codes in action:

## Creation of Example Data

We’ll use the data below as a basis for this Python programming tutorial.

my_list = [4, 1, 3, 8, 2, 7, 5, 8, 2, 7, 9, 1, 5] # Create example list print(my_list) # Print example list # [4, 1, 3, 8, 2, 7, 5, 8, 2, 7, 9, 1, 5] |

my_list = [4, 1, 3, 8, 2, 7, 5, 8, 2, 7, 9, 1, 5] # Create example list print(my_list) # Print example list # [4, 1, 3, 8, 2, 7, 5, 8, 2, 7, 9, 1, 5]

As you can see based on the previous output of the Python console, our example data is a list object containing several integer values.

## Example 1: Get Population Standard Deviation Using pstdev() Function of statistics Module

Example 1 illustrates how to calculate the population standard deviation using the pstdev function of the statistics module.

For the examples of this tutorial, we’ll first have to load the statistics module:

import statistics # Import statistics |

import statistics # Import statistics

Next, we can apply the statistics.pstdev function to our example list as shown below:

print(statistics.pstdev(my_list)) # Apply pstdev() function # 2.7218163096852512 |

print(statistics.pstdev(my_list)) # Apply pstdev() function # 2.7218163096852512

As you can see, the population standard deviation of our example list is 2.72.

## Example 2: Get Sample Standard Deviation Using stdev() Function of statistics Module

In this example, I’ll demonstrate how to find and get the sample standard deviation of a list using the statistics module.

For this task, we can apply the stdev function (note the missing p at the beginning of the function name) to our list:

print(statistics.stdev(my_list)) # Apply stdev() function # 2.8329562343320847 |

print(statistics.stdev(my_list)) # Apply stdev() function # 2.8329562343320847

The sample standard deviation is slightly higher than the population standard deviation that we have computed in Example 1.

## Video & Further Resources

Do you need more information on the Python syntax of this tutorial? Then I recommend having a look at the following video which I have published on my YouTube channel. I illustrate the contents of this article in the video.

*The YouTube video will be added soon.*

In addition, you may want to read the other articles on my homepage.

- Standard Deviation in Python
- Standard Deviation by Group
- Standard Deviation of NumPy Array
- Variance in Python
- Introduction to Python

Summary: At this point you should have learned how to **apply the stdev and pstdev functions of the statistics module** in the Python programming language. If you have any further questions, please let me know in the comments section.