Скачать или смотреть How to Create a New Column and Rename Files in Linux Using awk

Learn how to create a new column and rename files in Linux with a step-by-step guide using `awk` and shell commands.
---
This video is based on the question https://stackoverflow.com/q/71685141/ asked by the user 'pierogi' ( https://stackoverflow.com/u/17015085/ ) and on the answer https://stackoverflow.com/a/71685378/ provided by the user 'jared_mamrot' ( https://stackoverflow.com/u/12957340/ ) 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: create the column and rename the files of second column to new column in linux?

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 Create a New Column and Rename Files in Linux Using awk

Managing files in Linux efficiently can often require batch renaming based on specific criteria or formats. One common need is to manipulate file names in a structured way, especially when they follow a predictable pattern. In this guide, we will dive into a practical example where we create a new column in a data file and rename the files based on the newly created column using awk. Let’s get started!

Understanding the Problem

Suppose you have a file named lookup.tsv that lists the filenames you want to work with. Here’s a snippet of what the data looks like:

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

Desired Outcome

Create a New Column: From the existing filenames in the first column, create a second column where the filenames are formatted as SRR_<row_number>.fastq. For example:

From SRR7015874_1.fastq, create SRR_1.fastq.

From SRR7015875_2.fastq, create SRR_4.fastq, etc.

Final Task: Add a third column that rewrites the filenames into a simpler format like SRR1_1.fastq, SRR2_1.fastq, etc., and then rename the original files based on this new column.

Step-by-Step Solution

Step 1: Create the Second Column

We'll start by creating the second column with the following awk command:

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

This command processes each line of lookup.tsv and prints out the original filename followed by a tab and a newly formatted filename based on the row number.

Step 2: Create the Third Column

Next, we need to create the third column that rewrites the filenames into the desired format. We’ll use another awk command for this purpose:

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

This command iterates over the numbers and constructs filenames based on the specified pattern.

Step 3: Combine Columns into a Lookup Table

Now, let’s merge tmp and third_column.txt into a single file that holds all three columns:

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

This will create a new file lookup_table.txt that looks like this:

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

Step 4: Rename the Files

Finally, we will rename the original files using the mappings in the new lookup table. Run the following command in your terminal:

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

Each line of lookup_table.txt will be read, and the files will be renamed accordingly.

Conclusion

By following these steps, you can effectively automate the creation of new columns in your TSV files and perform batch renaming of files in Linux using awk and simple shell commands. This method is not only efficient but can also save you a significant amount of time when dealing with large datasets. Happy coding!