Python Program to Sort a List in Descending Order

Introduction

Sorting a list in descending order is a common task in programming, especially when you need to organize data from highest to lowest. This tutorial will guide you through creating a Python program that sorts a given list of numbers in descending order.

Example:

Input: [3, 5, 7, 2, 8]
Output: [8, 7, 5, 3, 2]
Input: [15, 22, 9, 3, 6, 27]
Output: [27, 22, 15, 9, 6, 3]

Problem Statement

Create a Python program that:

Takes a list of numbers as input.
Sorts the list in descending order.
Displays the sorted list.

Solution Steps

Take Input from the User: Use the input() function to get a list of numbers from the user.
Convert Input to a List of Integers: Convert the input string to a list of integers.
Sort the List in Descending Order: Use the sort() method or the sorted() function with the reverse=True argument to sort the list in descending order.
Display the Sorted List: Use the print() function to display the sorted list.

Python Program

# Python Program to Sort a List in Descending Order
# Author: https://www.rameshfadatare.com/

# Step 1: Take input from the user
input_list = input("Enter a list of numbers separated by spaces: ")

# Step 2: Convert the input string to a list of integers
numbers = list(map(int, input_list.split()))

# Step 3: Sort the list in descending order
numbers.sort(reverse=True)  # Or you can use: numbers = sorted(numbers, reverse=True)

# Step 4: Display the sorted list
print(f"The sorted list in descending order is: {numbers}")

Explanation

Step 1: Take Input from the User

The input() function prompts the user to enter a list of numbers, separated by spaces. The input is stored as a string in the variable input_list.

Step 2: Convert Input to a List of Integers

The split() method is used to split the input string into individual components, and map(int, ...) is used to convert these components into integers. The list() function then creates a list of these integers.

Step 3: Sort the List in Descending Order

The sort() method is used with the reverse=True argument to sort the list in place in descending order. Alternatively, the sorted() function can be used with the reverse=True argument to return a new sorted list in descending order.

Step 4: Display the Sorted List

The print() function is used to display the sorted list.

Output Example

Example 1:

Enter a list of numbers separated by spaces: 3 5 7 2 8
The sorted list in descending order is: [8, 7, 5, 3, 2]

Example 2:

Enter a list of numbers separated by spaces: 15 22 9 3 6 27
The sorted list in descending order is: [27, 22, 15, 9, 6, 3]

Example 3:

Enter a list of numbers separated by spaces: 1 100 50 23
The sorted list in descending order is: [100, 50, 23, 1]

Conclusion

This Python program demonstrates how to sort a list of numbers in descending order using the sort() method or the sorted() function with the reverse=True argument. This is a fundamental operation in Python programming, and understanding it is essential for working with lists and data structures effectively.