Скачать или смотреть Randomizing a Text File in Linux Without Consecutive Duplicates

Discover how to effectively randomize lines in a text file on Linux while ensuring no consecutive duplicates appear. Learn step-by-step instructions using awk.
---
This video is based on the question https://stackoverflow.com/q/77058765/ asked by the user 'DarrenB' ( https://stackoverflow.com/u/4792610/ ) and on the answer https://stackoverflow.com/a/77060945/ provided by the user 'markp-fuso' ( https://stackoverflow.com/u/7366100/ ) 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: Randomize txt file in Linux but guarantee no repetition of lines

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 Randomize a Text File in Linux Without Consecutive Duplicates

If you've ever worked with text files in Linux, you might have encountered the need to randomize the lines of a file. While several methods exist for randomizing lines, ensuring that no text appears consecutively — especially when dealing with duplicates — can pose a unique challenge. In this guide, we will explore a solution tailored to this problem, utilizing awk to accomplish our goal.

Understanding the Problem

Imagine you have a text file named test.txt that contains the following lines:

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

Our goal is to randomize these lines while ensuring that duplicate lines (e.g., "Line 3") do not appear on consecutive lines. This means that if a duplicate line is selected, it should be separated by at least one different line.

Proposed Solution

To achieve this, we'll implement a structured method using awk. The approach consists of maintaining two arrays:

One for lines that occur only once (single[])

Another for lines that occur multiple times (multi[])

Here's how we can set it up:

Count Line Occurrences: Use an associative array to count how many times each line appears in the file.

Allocate Lines in Arrays:

If a line appears only once, it'll go into the single[] array.

If a line appears multiple times, each instance will be added to the multi[] array.

Random Output Generation: Mix the entries from single[] and multi[] arrays during output to prevent consecutive duplicates.

Step-by-step Implementation

Below is a sample awk script to implement this solution.

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

How to Use the Script

Create Your Text File: Save your lines in test.txt.

Save the Script: Save the above awk script as dupes.awk.

Run the Script: Execute the following command in your terminal:

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

Example Output

When you run the script, it will provide an output similar to the following (note that output will vary with each execution):

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

This output ensures that the duplicate "Line 3" does not appear consecutively.

Conclusion

Randomizing lines in a text file on Linux while avoiding consecutive duplicates can be tricky, but with the method demonstrated above using awk, you can achieve exactly that. This approach allows you to keep your files organized and ensures better readability or processing in subsequent applications.

Feel free to use and adapt this script for your needs, and share your experiences or questions in the comments below!