Скачать или смотреть How to Order a List of Lists in Python by the Length of the Second Element

Discover how to effectively sort a list of lists in Python based on the length of the second elements using a lambda function.
---
This video is based on the question https://stackoverflow.com/q/64505342/ asked by the user 'TheObands' ( https://stackoverflow.com/u/11490591/ ) and on the answer https://stackoverflow.com/a/64505384/ provided by the user 'Ironkey' ( https://stackoverflow.com/u/11748253/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Order list of lists by length of second element in sublist python

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Sorting a List of Lists in Python by the Length of the Second Element

Have you ever struggled with sorting nested lists in Python? One common scenario is needing to order a list of lists based on the length of the second element in each sublist. This is a prevalent requirement when dealing with structured data arrays where individual items contain varying amounts of information.

For example, consider the following list of lists:

[[See Video to Reveal this Text or Code Snippet]]

In this structure, each item within the list consists of a sublist that contains another list and a numerical list. Our goal is to sort this list by the length of the second element in each sublist.

This may sound straightforward, but knowing how to implement it correctly can make all the difference. Let’s dive into the solution!

Understanding the Problem

To clarify the requirement, we need to sort the list such that the sublists are ordered according to the length of their second element.

In our example, the second elements are [3, 4], [3, 4, 5, 6], and [3, 4, 5, 6, 5, 7, 8, 9], which have lengths of 2, 4, and 8, respectively. The desired sorted result should therefore look like this:

[[See Video to Reveal this Text or Code Snippet]]

The Solution

Using the sorted() Function

The built-in sorted() function provides a clean and efficient way to sort lists based on custom criteria. To sort our list by the length of the second element, we can utilize a lambda function as follows:

[[See Video to Reveal this Text or Code Snippet]]

Code Implementation

Here’s the complete code demonstrating this sorting method:

[[See Video to Reveal this Text or Code Snippet]]

Explanation of How It Works

The lambda function: This anonymous function takes one parameter (x), which represents each sublist in lst.

Length calculation: The expression len(x[1]) calculates the length of the second element.

Sorting: The sorted() function processes this list by comparing the lengths obtained from the lambda function, arranging them in ascending order.

The result can be confirmed by checking:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By using the combination of the sorted() function and a lambda expression, we can effectively order lists of lists in Python by a specific element's length. This method is not only efficient but also keeps your code clean and easy to understand.

Now you have the knowledge to sort nested lists effortlessly based on the length of any sub-elements you choose. Happy coding!