Paul Meagher submitted an item earlier about another article that might be of interest to some of our readers out there over on PHPMath.com - Computer algebra systems.

There are many mature math libraries out there and the question naturally arises why I don't give up on the PHP Math project and just create a binding or web interface to one of them. For those who don't appreciate the amount of learning that goes on when you implement a mathematical algorithm from the ground up, I am not going to convince you because you are a math user not a mathematical programmer.

For me, the only way to really learn math is to implement the math algorithms myself in PHP. This is a process that involves finding about 5 or so good reference books on the mathematical concepts and computations involved, doing a bunch of searches for related articles and code snippets, then developing some code that reproduces the results from a good test example you have to work with. Once you have the code reproducing the example results, then you can start to refine and extend the API to handle other examples and to provide more features.

He goes on, talking about some of the other people that have worked with this idea as well, including another project, STACK. The nearest we have to a CAS in PHP is the Math_RPN library. I would like to see this project either evolve into a CAS or see a new project with this objective (MATH_CAS). It is definately worth looking over Chris' work to better understand what a CAS system should offer.