7 replies to this topic

[TheNut]

Does anyone know of a free c++ library that takes a formula as a string and returns the result as a float/double? It would be nice if it supports complex mathematics such as calculus and whatnot, but at bare minimum I need something that can parse and calculate basic math and trigonometry.

It's primarily used for a graphing application I'm working on.

Thanks.

[monjardin]

I use GNU bc from time to time. It's a command line utility as opposed to a library, but it would do the trick. Also, what about executing the strings as Lua code?

[Reedbeta]

In the event you can't find a library that works for you, it wouldn't be very hard at all to build a parser using antlr or bison that would do the job (including evaluating expressions).

[martinsm]

Here's some links:
http://muparser.sourceforge.net/
http://www.codeproje...MathParser.aspx

[Nils Pipenbrinck]

http://smallcode.weblogs.us/

Scroll down a bit and you'll find a expression evaluator code with variables and dynamic code generation.

Nils

[TheNut]

Thanks, these are all good. I'll spend some time tonight going through each one and checking them out.

[Nils Pipenbrinck]

Let us know which one you'll use :-)

Nils

[SmokingRope]

One of the first few chapters in The C++ Programming Language covers the basics of writing a symbolic calculator yourself (without grammars, parser tables, etc... ).