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Python Sort Lists – Everything You Need to Know

Sorting is a fundamental operation in any computer programming language. It allows you to organise data in a desired order for easier manipulation and analysis. In this article, we will learn how to sort the list in Python using the sort() method, which is an inbuilt method in the Python programming language.

sort() method in Python

In the Python programming language, we have asort() method. This is an inbuilt method that sorts the original list directly.

Syntax of sort() method

This method accepts two parameters that are described below:

• reverse(Optional): This is an optional parameter. If this parameter is true, it will sort the
  list in reverse order. By default, this parameter has a false value.
• key(Optional): This parameter is also optional. This parameter specifies the sorting criteria.

Sort list items in ascending order

By default, the sort() method sorts the list in ascending order. Ascending order means arranging the
items from lowest to highest value. The lowest value will be the left-hand side, and the highest value will be the
right-hand side.

The following program demonstrates sorting the list of numbers in ascending order.

Source Code

Output

Also read: Python Data Types

Sort list items in descending order

Descending sorting is the opposite of ascending order. In descending order, we sort the elements and arrange them from highest to lowest value. To sort the list in descending order, you have to enable the reverse parameter in the sort() method. Its value must be true when working with descending sorting.

The following program demonstrates sorting the list of items in descending order.

Source Code

Output

We can also perform customised sorting operations by using the key parameter. The key parameter accepts a function that specifies which type of sorting you are performing. In this example, we will pass the inbuilt len() function into the key parameter for sorting the list of elements.

The following program demonstrates the sort() method with the key parameter:

Source Code:

Output

Also read: Lambda Function in Python

Sort a list of strings

We can also sort the list of strings using the sort() method. The following program demonstrates the list of string examples.

Program

Output

The difference between sort() and sorted() method

The Python programming language has one more method, sorted(). In this section, we will try to differentiate the sort() and sorted() methods.

Conclusion

Every developer must know how to sort a list in Python. This is a fundamental skill every developer should master this skill. In this article, we learned about various kinds of approaches for sorting the list in Python. There are two inbuilt methods in Python for sorting a list: the ‘sort()’ and ‘sorted()’ methods. Both methods sort the array. The first method does not return any sorted list. However, the second method returns the sorted list. If you want to learn more about the Python language, enrol in the Accelerator Program in Business Analytics and Data Science.