[R] Passing equations as arguments

[jim holtman]

Here is one possible solution:

ifun <-
function(a, b, FUN){
    evala <- FUN(a)
    evalb <- FUN(b)
    if (evala > evalb) return(evala) else return(evalb)
}
ifun(1,2,function(x) (x*x) - 2)



On 7/24/07, Anup Nandialath <anup_nandialath at yahoo.com> wrote:
> Friends,
>
> I'm trying to pass an equation as an argument to a function. The idea is as follows. Let us say i write an independent function
>
> Ideal Situation:
>
> ifunc <- function(x)
> {
> return((x*x)-2)
> }
>
> mainfunc <- function(a,b)
> {
> evala <- ifunc(a)
> evalb <- ifunc(b)
> if (evala>evalb){return(evala)}
> else
> return(evalb)
> }
>
> Now I want to try and write this entire program in a single function with the user specifying the equation as an argument to the function.
>
> myfunc <- function(a, b, eqn)
> {
>    func1 <- function (x) ??????????????????
>        {
>            return(eqn in terms of x)  ??????????????????
>       }
>
> Further arguments to check
>
> The ???????? imply that this does not seem to be correct. The idea is how to assign the equation expression from the main equation into the inner function. Is there anyway to do that within this set up?
>
>
> Thanks in advance
> Regards
>
> Anup
>
>
> ---------------------------------
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>


-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem you are trying to solve?