LabEx
Log In Join For Free

Efficient Prime Number Detection

PythonPythonBeginner
Practice Now

This tutorial is from open-source community. Access the source code

Introduction

In mathematics, a prime number is a natural number greater than 1 that is not a product of two smaller natural numbers. For example, 5 is prime because the only ways of writing it as a product, 1 × 5 or 5 × 1, involve 5 itself. However, 4 is not prime because it is a product (2 × 2) in which both numbers are smaller than 4. In this challenge, you need to write a Python function to check if a given number is prime or not.

Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL python(("`Python`")) -.-> python/BasicConceptsGroup(["`Basic Concepts`"]) python(("`Python`")) -.-> python/ControlFlowGroup(["`Control Flow`"]) python(("`Python`")) -.-> python/DataStructuresGroup(["`Data Structures`"]) python(("`Python`")) -.-> python/FunctionsGroup(["`Functions`"]) python(("`Python`")) -.-> python/ModulesandPackagesGroup(["`Modules and Packages`"]) python(("`Python`")) -.-> python/PythonStandardLibraryGroup(["`Python Standard Library`"]) python/BasicConceptsGroup -.-> python/comments("`Comments`") python/BasicConceptsGroup -.-> python/variables_data_types("`Variables and Data Types`") python/BasicConceptsGroup -.-> python/numeric_types("`Numeric Types`") python/BasicConceptsGroup -.-> python/booleans("`Booleans`") python/BasicConceptsGroup -.-> python/type_conversion("`Type Conversion`") python/ControlFlowGroup -.-> python/conditional_statements("`Conditional Statements`") python/ControlFlowGroup -.-> python/for_loops("`For Loops`") python/DataStructuresGroup -.-> python/tuples("`Tuples`") python/FunctionsGroup -.-> python/function_definition("`Function Definition`") python/ModulesandPackagesGroup -.-> python/importing_modules("`Importing Modules`") python/ModulesandPackagesGroup -.-> python/using_packages("`Using Packages`") python/ModulesandPackagesGroup -.-> python/standard_libraries("`Common Standard Libraries`") python/PythonStandardLibraryGroup -.-> python/math_random("`Math and Random`") python/FunctionsGroup -.-> python/build_in_functions("`Build-in Functions`") subgraph Lab Skills python/comments -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/variables_data_types -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/numeric_types -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/booleans -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/type_conversion -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/conditional_statements -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/for_loops -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/tuples -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/function_definition -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/importing_modules -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/using_packages -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/standard_libraries -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/math_random -.-> lab-13672{{"`Efficient Prime Number Detection`"}} python/build_in_functions -.-> lab-13672{{"`Efficient Prime Number Detection`"}} end

Number is Prime

Write a Python function called is_prime(n) that takes an integer n as input and returns True if the number is prime, and False otherwise. To solve this problem, you need to follow these rules:

  • Return False if the number is 0, 1, a negative number or a multiple of 2.
  • Use all() and range() to check numbers from 3 to the square root of the given number.
  • Return True if none divides the given number, False otherwise.
from math import sqrt

def is_prime(n):
  if n <= 1 or (n % 2 == 0 and n > 2):
    return False
  return all(n % i for i in range(3, int(sqrt(n)) + 1, 2))
is_prime(11) ## True

Summary

In this challenge, you learned how to check if a given number is prime or not using Python. You used the all() and range() functions to check numbers from 3 to the square root of the given number. You also learned how to return True if none divides the given number, False otherwise.

Other Python Tutorials you may like

Related Python Courses
Quick Start with Python

Quick Start with Python

LinuxPython
Beginner
Python Practice Labs

Python Practice Labs

Python
Beginner
Python Practice Challenges

Python Practice Challenges

Python
Beginner

We use cookies for a number of reasons, such as keeping the website reliable and secure, to improve your experience on our website and to see how you interact with it. By accepting, you agree to our use of such cookies. Privacy Policy