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Python Polars: The Definitive Guide
book

Python Polars: The Definitive Guide

by Jeroen Janssens, Thijs Nieuwdorp
February 2025
Intermediate to advanced
504 pages
11h 31m
English
O'Reilly Media, Inc.
Content preview from Python Polars: The Definitive Guide

Chapter 18. Polars Internals

In this chapter, we dive deep into the inner workings of Polars, uncovering the mechanisms that make it such a powerful and efficient data manipulation package. Throughout the book, you’ve encountered references to this chapter for a more comprehensive understanding of Polars’ functionality.

In this chapter, you’ll learn about:

  • The architecture of Polars

  • Some technologies under the hood

  • Some optimizations that enable Polars’ performance

  • Tools to profile and test your code, ensuring that you can optimize your data processing tasks to the fullest

The instructions to get any files you might need are in Chapter 2. We assume that you have the files in the data subdirectory.

By the end of this chapter, you’ll have a deeper appreciation for the engineering that goes into making Polars fast and efficient, as well as practical knowledge on how to leverage these internals for your own data processing tasks.

Polars’ Architecture

Everything starts with your code. The code you type is in Polars’ domain-specific language (DSL). This DSL allows you to define what should be done in a declarative manner.

The DSL is then transformed into an intermediate representation (IR) that is a more abstract representation of the work that needs to be done. You can view this IR by calling lf.explain() to get its String representation, or you can visualize it with lf.show_graph(). The IR is represented as a directed acyclic graph (DAG) where each node represents a computation ...

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Publisher Resources

ISBN: 9781098156077Errata Page