Jay, what I was kind thinking of for (x^2-5x+y+y^2)/100*dt is somthing that treates parenthases, as varables. I'm not so concerned with precision, I can handle that. I could use an algorithm that would figure out that X should first be squared, and secondly x should multiplied by 5, and so on. The routine I wrote scans for the most internal parenthases and stores the operands and operation, and marks those except for the first operand. Its kind of faccenating to watch the pragram output the order of the operands to be used. THe output here would be something like:

found found found
( ( (
x*x y xa+xb+xc
) ) )
found found found
( ( (
-5*x y*y x1/x2
) ) )