Poisson Distribution in NumPy Last Updated : 22 Apr, 2025 Summarize Comments Improve Suggest changes Share Like Article Like Report The Poisson Distribution model the number of times an event happens within a fixed time or space when we know the average number of occurrences. It is used for events that occur independently such as customer arrivals at a store, Website clicks where events happen independently.numpy.random.poisson() MethodIn Python'sNumPylibrary we can generate random numbers following a Poisson Distribution using the numpy.random.poisson() method. It has two key parameters:lam : The average number of events (λ) expected to occur in the interval.size : The shape of the returned array.Syntax:numpy.random.poisson(lam=1.0, size=None)Example 1: Generate a Single Random NumberTo generate a single random number from a Poisson Distribution with an average rate of λ = 5: Python import numpy as np random_number = np.random.poisson(lam=5) print(random_number) Output :5Example 2: Generate an Array of Random NumbersTo generate multiple random numbers: Python random_numbers = np.random.poisson(lam=5, size=5) print(random_numbers) Output :[13 6 4 4 10]Visualizing the Poisson DistributionTo understand the distribution better we can visualize the generated numbers. Here is an example of plotting a histogram of random numbers generated using numpy.random.poisson. Python import numpy as np from numpy import random import matplotlib.pyplot as plt import seaborn as sns lam = 2 size = 1000 data = random.poisson(lam=lam, size=size) sns.displot(data, kde=False, bins=np.arange(-0.5, max(data)+1.5, 1), color='skyblue', edgecolor='black') plt.title(f"Poisson Distribution (λ={lam})") plt.xlabel("Number of Events") plt.ylabel("Frequency") plt.grid(True) plt.show() Output:Poisson DistributionThe image shows a Poisson Distribution with λ=2 displaying the frequency of events. The histogram represents simulated data highlighting the peak at 0 and 1 events, with frequencies decreasing as the number of events increases. Comment More infoAdvertise with us Next Article Poisson Distribution in NumPy J jitender_1998 Follow Improve Article Tags : Python Python-numpy Python numpy-Random Practice Tags : python Similar Reads Python Tutorial - Learn Python Programming Language Python is one of the most popular programming languages. Itâs simple to use, packed with features and supported by a wide range of libraries and frameworks. Its clean syntax makes it beginner-friendly. It'sA high-level language, used in web development, data science, automation, AI and more.Known fo 10 min read Python Interview Questions and Answers Python is the most used language in top companies such as Intel, IBM, NASA, Pixar, Netflix, Facebook, JP Morgan Chase, Spotify and many more because of its simplicity and powerful libraries. To crack their Online Assessment and Interview Rounds as a Python developer, we need to master important Pyth 15+ min read Python OOPs Concepts Object Oriented Programming is a fundamental concept in Python, empowering developers to build modular, maintainable, and scalable applications. By understanding the core OOP principles (classes, objects, inheritance, encapsulation, polymorphism, and abstraction), programmers can leverage the full p 11 min read Python Projects - Beginner to Advanced Python is one of the most popular programming languages due to its simplicity, versatility, and supportive community. Whether youâre a beginner eager to learn the basics or an experienced programmer looking to challenge your skills, there are countless Python projects to help you grow.Hereâs a list 10 min read Python Exercise with Practice Questions and Solutions Python Exercise for Beginner: Practice makes perfect in everything, and this is especially true when learning Python. If you're a beginner, regularly practicing Python exercises will build your confidence and sharpen your skills. To help you improve, try these Python exercises with solutions to test 9 min read Python Programs Practice with Python program examples is always a good choice to scale up your logical understanding and programming skills and this article will provide you with the best sets of Python code examples.The below Python section contains a wide collection of Python programming examples. These Python co 11 min read Python Introduction Python was created by Guido van Rossum in 1991 and further developed by the Python Software Foundation. It was designed with focus on code readability and its syntax allows us to express concepts in fewer lines of code.Key Features of PythonPythonâs simple and readable syntax makes it beginner-frien 3 min read Python Data Types Python Data types are the classification or categorization of data items. It represents the kind of value that tells what operations can be performed on a particular data. Since everything is an object in Python programming, Python data types are classes and variables are instances (objects) of thes 9 min read Input and Output in Python Understanding input and output operations is fundamental to Python programming. With the print() function, we can display output in various formats, while the input() function enables interaction with users by gathering input during program execution. Taking input in PythonPython input() function is 8 min read Enumerate() in Python enumerate() function adds a counter to each item in a list or other iterable. It turns the iterable into something we can loop through, where each item comes with its number (starting from 0 by default). We can also turn it into a list of (number, item) pairs using list().Let's look at a simple exam 3 min read Like