Welcome to Formulate’s documentation!

Formulate is a Python library for easy conversions between different styles of expressions. It converts in either direction between ROOT (TTreeFormula) and numexpr syntax, and can also render any parsed expression as plain Python using NumPy functions.

>>> import formulate
>>> formulate.from_root("TMath::Sqrt(px**2 + py**2) > 10").to_numexpr()
'(sqrt(((px ** 2) + (py ** 2))) > 10)'

Install it with pip install formulate or conda install -c conda-forge formulate, then start with the Introduction.

Quickstart

• Introduction
  • What is Formulate?
  • Simple example
  • Key features
  • What Formulate is not
• Installation
  • Using pip
  • Using conda
  • From Source
  • Verifying Installation
• Simple Example
  • Basic Usage
  • Converting from ROOT to numexpr
  • Converting from numexpr to ROOT
  • Converting to Python
  • Inspecting an expression
  • Using the Converted Expressions
  • When a conversion is not possible
  • CLI Usage
• What’s New
  • Changelog

Guide

• Supported Expressions
  • Operators
  • Indexing
  • Functions
  • Constants
  • Inspecting an expression
  • Limitations
• Performance Considerations
  • Parse once, render many times
  • The grammars are compiled lazily, once
  • Expression size
  • What formulate does not affect
• Common Issues
  • % does not mean the same thing in ROOT and numexpr
  • Constructs with no equivalent raise rather than approximating
  • ^ is exponentiation in ROOT and XOR in numexpr
  • Logical operators bind differently in the two languages
  • Named constants do not survive a round trip through numexpr
  • Dotted branch names are hex-encoded for numexpr

API

• API Reference
  • formulate
  • Abstract Syntax Tree (AST)
  • Identifiers
  • Parse tree conversion
  • Exceptions

Contributing

• Contributing to Formulate
  • Setting Up Your Development Environment
  • Development Workflow
  • Using nox
  • Coding Guidelines
  • Adding a function or a constant
  • Types of Contributions

Project

• Citing Formulate
  • Citing the package
  • Citing Scikit-HEP
  • Citing what formulate converts to
• Project Information
  • About Formulate
  • Maintainers
  • Getting in Touch
  • Contributing
  • Code of Conduct
  • License

Ask a Question

• Ask a Question
  • Where to Ask Questions
  • How to Ask Effective Questions
  • Common Questions
  • Getting Involved

Indices and tables

• Index

• Module Index

• Search Page