Ay Joselito wrote: > I want to develop an application
in which the user enters a mathematical equation, presumably as a string (any arbitrary equation, using any of the standard mathematical operators : +,*,^, etc, and any of the standard functions: sin, exp, etc.). I need to take that string, convert it to a real function, and evaluate it.
First you need to parse the expression into a Haskell data type. For this I would recommend Parsec (see Haskell.org). The Haskell data type would be something like
data Expr = AtomD Double | AtomI Integer | Add Expr Expr | Mul Expr Expr | Sub Expr Expr | ....
Then when you've parsed the expression you need to evaluate it. This should be fairly straightforward (pattern match against the constructors and perform the necessary operations recursively).
Good luck.
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