Python Polars: The Definitive Guide: Transforming, Analyzing, and Visualizing Data with a Fast and Expressive DataFrame API

Jeroen Janssens, Thijs Nieuwdorp

Unlock the power of Polars, a Python package for transforming, analyzing, and visualizing data. In this hands-on guide, Jeroen Janssens and Thijs Nieuwdorp walk you through every feature of Polars, showing you how to use it for real-world tasks like data wrangling, exploratory data analysis, building pipelines, and more.

Whether you’re a seasoned data professional or new to data science, you’ll quickly master Polars’ expressive API and its underlying concepts. You don’t need to have experience with pandas, but if you do, this book will help you make a seamless transition. The many practical examples and real-world datasets are available on GitHub, so you can easily follow along.

Process data from CSV, Parquet, spreadsheets, databases, and the cloud
Get a solid understanding of Expressions, the building blocks of every query
Handle complex data types, including text, time, and nested structures
Use both eager and lazy APIs, and know when to use each
Visualize your data with Altair, hvPlot, plotnine, and Great Tables
Extend Polars with your own Python functions and Rust plugins
Leverage GPU acceleration to boost performance even furthe