Runtime Expression Parsing:

I have compared and evaluated these parsers. Here are the results.

EquationEvaluator - plugin - carbon and ppc
I have a plugin that works with RB 2.1 - 4.5 (ppc and carbon, not tested with RB 5)
This one takes just one line, something like "x=5; 3*x" and returns the answer as a double: 15.0. I have found this handy in the cgi that I wrote. I think it is a good choice if you only want an answer for one equation done once (in other words, it works great in a cgi, but it is slow if you want to plot an equation - each time you send the equation through the parser you lose time). More about it here

Expression Evaluator - class
Created by Steve LoBosso: This is written all in RB code, so it is probably slower than a comparable plug-in (like the Equation Compiler Plugin by Bob Delany, below). But, since you can see the source code you can modify it yourself, adding functions if you need to. Steve also has a set of classes that can be used to do matrix math.

Equation Compiler Plugin - plugin - carbon, ppc, and windows
By Bob Delaney (who has lots of other plug-ins, below). This one compiles your equation and then you can access it as though it was a built in function. It comes with the source code to his Newton's Method program.

Eval - class
EvilEval - plugin - ppc only
Adrian Platts has several things on his web page - a couple of different plug-ins that allow runtime equation evaluation (Eval and EvilEval), and also a couple of math plug-ins that speed up calculations in RealBasic (ScreenMath and AfterMath). He also has a nifty function plotter, which can be used to plot functions of the form z = x + y.

RBScript Example
Naturally, this is the sort of thing that RBScript should be able to do.


Other Useful Math Plug-ins/Classes

A Fast Fourier Transform plug-in can be found at

Complex number math
One of many things that Jon's RealBasic Classes do is Complex number math. If you need this sort of thing then you might want to check it out. jons-realbasic-classes are available on Info-Mac

Matrix Math
Steve LoBosso: (mentioned above) also has some classes to do matrix math.

More Matrix Math
Here are some other matrix classes, along with good examples of how to use them. These come from Rodney Dyer, who is no longer developing or supporting them. I've rescued the classes and they are now on my ftp server

Bob Delaney
has lots of math software available (see Equation Compiler Plugin, above) - MPCalc plugin, which is basically all the routines used in his RPN calculator. Precision Plugin, which can handle numbers with 30,000 decimal digits with absolute values of 1e-40000000 and 1e+40000000.

Faster Math Evaluation
By Adrian Platts, creator of Eval and EvilEval (see above)


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