Question

Possible Duplicate:
What is a fast C or Objective-C math parser?

I have a create a function which takes a formula as a NSString. And I have to replace few things in the String and get the value after executing the formula. How can I do this…

Ex: NSString *formulaString = @”((A/B)-1)*100″;

Now I can replace A by 20, and B by 10.
But how will get calculated value that is ((20/10)-1)*100 as 100

Thanks,
Ben

Answer 1

You can replace the characters by this method

NSString *formulaString = @"((A/B)-1)*100";

NSString *modifiedFormulaString = [formulaString stringByReplacingOccurrencesOfString:@"A" withString:@"10"];

modifiedFormulaString = [modifiedFormulaString stringByReplacingOccurrencesOfString:@"B" withString:@"10"];

But to calculate dat u need to parse it using some parser.