Python While Loop

 

A while loop in Python repeatedly executes a block of code as long as a given condition is True. Once the condition becomes False, the program control proceeds to the next statement after the loop.

Here is an example of a simple while loop that counts down from 10:

count = 10

while count > 0:

    print(count)

    count -= 1

In this example, the while statement is followed by the condition count > 0. The code block that follows the while statement is indented, indicating that it is part of the loop. The block of code in this example simply prints the current value of count and then decrements count by 1.

As long as the condition count > 0 is True, the loop will execute. Once count becomes 0, the condition is False and the loop will exit, and the next statement following the loop will be executed.

You can also use the break statement to exit a while loop. This can be useful if you want to exit the loop based on some condition that is checked within the loop. Here is an example:

while True:

    response = input("Enter a number: ")

    if response == 'q':

        break

    number = int(response)

    print("You entered:", number)

In this example, the while loop will run indefinitely because the condition is always True. However, the break statement is used to exit the loop when the user enters 'q'.

Also, the continue statement can be used to skip the current iteration of the loop and move on to the next iteration.

while True:

    response = input("Enter a number: ")

    if response == 'q':

        break

    if not response.isdigit():

        print("Invalid input. Please enter a number.")

        continue

    number = int(response)

    print("You entered:", number)

In this example, the continue statement is used to skip the current iteration if the response entered by the user is not a digit.

It is important to be careful when using while loops, as it can be easy to create an infinite loop if the condition is never false, or if the statement(s) inside the loop do not change the condition.

In conclusion, while loops are a powerful tool in Python for repeatedly executing a block of code as long as a given condition is True. They can be used for a variety of tasks, such as input validation, countdown, and many more.

Amelioration

This article was researched and written with the help of ChatGPT, a language model developed by OpenAI.

Special thanks to ChatGPT for providing valuable information and examples used in this article.