Polars: Chapter 09 - Strings

[peter-gy]

📝 Summary

This is my proposal for the first version of the Polars chapter on strings. My goal was to offer decent horizontal coverage of the expressions in the string namespace while ensuring the material is kept interactive and engaging through visualizations and a mini app.

You can try this notebook by executing:

uvx marimo run https://github.com/peter-gy/learn/blob/0a4006f71ed4a19f19c410bab8da7ff9ae75d31a/polars/09_strings.py --sandbox

The chapter is made up of the following sections:

• 🛠️ Parsing & Conversion
• 📊 Dataset Overview
• 📏 Length Calculation
• 🔠 Case Conversion
• ➕ Padding
• 🔄 Replacing
• 🔍 Searching & Matching
• ✂️ Slicing and Substrings
• ➗ Splitting
• 🔗 Concatenation & Joining
• 🔍 Pattern-based Extraction
• 🧹 Stripping
• 🔑 Encoding & Decoding
• 🚀 Application: Dynamic Execution of Polars Examples

📋 Checklist

• I have included package dependencies in the notebook file using --sandbox
• Keep language direct and simple. (This is subjective, I'm open to feedback to simplify language if needed)

[akshayka]

@peter-gy, this is absolutely beautiful. What a fantastic chapter — love the dataset, love the clarity of exposition, love the simplicity of the interactive examples.

The only very small comment I have is that we typically configure the notebook to hide the code of markdown cells, but I can do that in a follow up. Fantastic work.