Efficient Ways to Loop Over Files in Different Folders Using Python

Discover how to effectively loop over files in separate folders and filter them based on specific criteria using Python.
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Efficient Ways to Loop Over Files in Different Folders Using Python

When working with large volumes of data across different directories, it's common to encounter the need to loop over files within specific folders. For instance, you may have two folders on your computer named "apple" and "banana," and you want to filter for Excel files that contain certain keywords, such as "green" in "apple" and "yellow" in "banana." This task can become cumbersome if you attempt to manually handle the conditions for each folder, especially if the processing of the files is similar.

In this post, we will explore how to efficiently loop over files in separate folders using Python, specifically utilizing the glob and pathlib libraries for streamlined code and ease of use.

Understanding the Problem

The requirement is to scan two separate directories, "C:/Desktop/apple" and "C:/Downloads/banana," for specific Excel files that match your criteria:

In the apple folder, you want to find files containing the keyword green.

In the banana folder, you want to find files containing the keyword yellow.

The challenge also includes ensuring that each folder path is specified explicitly, avoiding the need to loop through unnecessary directories on the entire drive.

A Traditional But Cumbersome Approach

Initially, one could use a simple nested loop setup with os.walk, but this tends to lead to code duplication since you'll often find yourself repeating similar file processing steps for each folder. Here’s what a typical approach might look like:

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

This approach isn’t the most efficient because it leads to redundancy in reading and processing your DataFrame.

Streamlined Solutions

Solution Using glob

The glob module simplifies the process significantly, allowing you to use pattern matching to find files. Here’s how you can implement it:

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

This code snippet leverages the pattern-matching capabilities of glob to find all relevant files in one go.

You can customize the pattern, for example, if you only want files starting with "green," you could change the pattern to green*.xlsx.

Solution Using pathlib

Alternatively, pathlib offers a more object-oriented approach to handle filesystem paths. Here’s how you can achieve the same result with pathlib:

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

pathlib not only makes the code cleaner but also provides powerful methods for path manipulations.

Conclusion

Handling files in different folders efficiently can save you a significant amount of time and potential errors in your code. By leveraging the built-in libraries glob and pathlib, you can write cleaner, more efficient scripts that maintain clarity without unnecessary redundancies.

Whether you opt for glob or pathlib, you'll find that both methods offer unique advantages depending on your preferences for syntax and style. Give these methods a try in your own projects, and watch your file-processing tasks become much more manageable!