I need to parse strings that contain arithmetic equations, say:

"3*(4 + 7)/37" or even "3(4 + 7)/37"

(5/27)*3^4

63.581^33 also possibly written as pow(63.581, 33) or even 63.581^(33/4) (meaning to some pow(63.581, (33/4)))

I need to use some flexible and extensible parser that users many be able to adjust/fine tune to their needs and what I want out of such parser is 4 numbers; 1 numerator a denominator and (if they are not 1) their powers

Any ideas of implementations of such a thing

Thanks
lbrtchx