PHP JAMA

A PHP 4.x port of the Java Matrix (JAMA) package, designed for developers who thought PHP was an appropriate platform for calculating eigenvectors and LU decompositions.

Overview

PHP JAMA brought linear algebra capabilities to PHP during the early 2000s, porting the functionality of the Java Matrix package to make matrix operations accessible to PHP developers. This was created during an era when PHP was primarily used for web development, making mathematical computing libraries somewhat unconventional.

Features

The library provided PHP implementations of:

• Matrix Operations: Basic arithmetic operations on matrices
• Decompositions: LU, QR, SVD, and eigenvalue decompositions
• Linear Algebra: Solving linear systems and computing matrix properties
• Mathematical Functions: Determinants, ranks, norms, and other matrix properties

Historical Context

This project emerged during the PHP 4.x era (2000-2004) when:

• PHP was primarily a web scripting language
• Mathematical computing in PHP was rare and somewhat impractical
• Scientific computing was dominated by languages like MATLAB, Fortran, and C
• The choice to implement complex mathematical operations in PHP was… questionable

Technical Implementation

The port maintained compatibility with the original JAMA API while adapting to PHP’s type system and language constraints. This required careful handling of:

• PHP’s loose typing system for numerical computations
• Memory management for large matrix operations
• Performance considerations in an interpreted language

Legacy

While PHP has evolved significantly since the 4.x era, this project represents the experimental spirit of early 2000s development, where developers pushed languages into domains they weren’t necessarily designed for. It’s archived as both a technical achievement and a humorous reminder of questionable technology choices.

Documentation

Original documentation and code samples are available in the site archives.