Mathexpx

Mathexpx is a cross-language library that provides parsing, evaluation, and manipulation of mathematical expressions for software applications. It aims to be lightweight, predictable, and embeddable, supporting both client-side and server-side environments.

Key features include: support for standard arithmetic operators, parentheses, exponentiation, functions such as sin, cos, log, and sqrt, constants pi and e, handling of negative numbers and decimal literals, and the ability to define user functions.

Implementation: It uses a Pratt parser to tokenize and parse expressions into an evaluable tree; evaluation is numerical with a configurable precision; provides error reporting; supports multiple language bindings (JavaScript, Python, Java) through adapters.

History and license: Mathexpx originated as an open-source project to provide a portable expression engine for apps. It is developed by a community of contributors and distributed under an open-source license.

Applications and reception: widely used in calculators, educational apps, online assessments, and simulation tools; noted for small size and fast evaluation, with ongoing work to extend algebraic capabilities.