How to Find the Mean, Median, and Mode in Python Using NumPy

Python is a powerful programming language used for many different applications. Within Python, the NumPy library exists to simplify a range of mathematical and logical operations involving large number sets. If you’re looking to calculate the mean, median, or mode of an array with Python, NumPy will make your life much easier!

Step 1: Install and import the NumPy library

NumPy is not a built-in library in Python. So, the first step is to install NumPy. As part of this tutorial, we’ll use Python’s package installer pip. If you haven’t installed NumPy yet, you will need to run the following command in your terminal:

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pip install numpy

Once you have NumPy installed on your device, you can import it into your Python program using:

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import numpy as np

Step 2: Create your array

NumPy operates on arrays, so the next step is to create the array you will be using. In this tutorial, we’ll be working with a 1-dimensional array for simplicity. Creating arrays in NumPy is straightforward:

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your_array = np.array([0, 1, 2, 3, 4, 5])

Step 3: Calculate the mean

The mean is simply the average of all the numbers in your set. You can use the np.mean() function to easily calculate this:

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np.mean(your_array)

Step 4: Find the median

The median is the middle value of your dataset when it is in order. If there’s an even number of observations, the median will be the average of the two middle numbers. Here is how you can calculate the median using NumPy:

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np.median(your_array)

Step 5: Determine the mode

Finally, the mode is the number that appears most frequently in your dataset. Unfortunately, NumPy doesn’t have a built-in function to calculate the mode. You would need the SciPy library for this function. Here is how you can do it:

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from scipy import stats
mode = stats.mode(your_array, keepdims=True)
print(mode)

Full Program:

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import numpy as np
from scipy import stats
 
your_array = np.array([0, 1, 2, 3, 4, 5])
 
mean = np.mean(your_array)
print(f"The Mean is: {mean}")
 
median = np.median(your_array)
print(f"The Median is: {median}")
 
mode = stats.mode(your_array, keepdims=True)
print(f"The Mode is: {mode}")
\
 
The Mean is: 2.5
The Median is: 2.5
The Mode is: ModeResult(mode=array([0]), count=array([1]))

Conclusion:

As you can see, calculating the mean, median, and mode using Python and the NumPy library is straightforward and efficient. With just a few lines of code, you can perform these important statistical measures to analyze your data set in no time. Happy coding!