How to Filter Out Strings with Dates in yyyy-mm-dd Format from a List

Discover how to effectively filter a list of strings to retain only those in `yyyy-mm-dd` format using Python. Learn step-by-step procedures and tips! --- This video is based on the question https://stackoverflow.com/q/70086629/ asked by the user 'caasswa' ( https://stackoverflow.com/u/15905901/ ) and on the answer https://stackoverflow.com/a/70086704/ provided by the user 'S.B' ( https://stackoverflow.com/u/13944524/ ) 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: How to filter out strings from a list of strings with dates? 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. --- How to Filter Out Strings from a List of Strings with Dates In today's digital environment, managing data efficiently can often be a challenge, especially when dealing with strings. One common requirement is to filter out strings that meet a specific pattern, such as dates in a yyyy-mm-dd format. This guide will guide you through the steps to achieve this using Python. The Problem Statement Imagine you have a list containing several strings, some of which represent dates while others do not. For instance: [[See Video to Reveal this Text or Code Snippet]] You want to extract only the strings that are in the yyyy-mm-dd format, resulting in: [[See Video to Reveal this Text or Code Snippet]] But the challenge doesn't stop there. What if your list contains prefixes such as root/2021-11-11? In this case, you would expect to pull: [[See Video to Reveal this Text or Code Snippet]] The Solution To tackle this problem, we can leverage Python's datetime module, which allows us to parse dates and handle invalid formats seamlessly. Below is a step-by-step breakdown of how to filter the strings. Step 1: Import the Required Module Start by importing the datetime module: [[See Video to Reveal this Text or Code Snippet]] Step 2: Define Your List Next, define the list that contains both dates and non-date strings: [[See Video to Reveal this Text or Code Snippet]] Step 3: Create a Filtering Function Now, let's create a function that filters the strings based on their format. The function will split the string to isolate the last part (which is expected to be the date) and check if it matches the yyyy-mm-dd format: [[See Video to Reveal this Text or Code Snippet]] Step 4: Apply the Filter Finally, use a list comprehension to apply the filter function to your list: [[See Video to Reveal this Text or Code Snippet]] Example Output When you run the complete code, you'll get the output: [[See Video to Reveal this Text or Code Snippet]] Conclusion Filtering out strings that match a specific date format from a list doesn't have to be complicated. By using Python's datetime module and a simple filtering function, you can efficiently achieve your goal and keep your data structured. By following the steps in this guide, you have gained a clear understanding of how to filter strings in yyyy-mm-dd format, whether they have prefixes or not. This technique can help you manage your data more effectively and save time in any coding project!