R help - Feb 2012 - calling the function which is stored in a list

Hi

I'm storing two functions in a list

# creating two function
  function1 <- function(n) {
  return(sum(n))
}

function2 <- function(n) {
  return(mean(n))
}

#storing the function 
function3 =c(function1,function2)

is it possible to call the stored function and used it ?

 x=c(10,29)
funtion3[1](x)

Thanks

-----
Thanks in Advance
        Arun
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On 09.02.2012 08:54, arunkumar1111 wrote:
> Hi
>
> I'm storing two functions in a list
>
> # creating two function
>    function1<- function(n) {
>    return(sum(n))
> }
>
> function2<- function(n) {
>    return(mean(n))
> }
>
> #storing the function
> function3 =c(function1,function2)
>
> is it possible to call the stored function and used it ?
>
>   x=c(10,29)
> funtion3[1](x)

Yes, if you correct the typo and use list indexing with double brackets:

function3[[1]](x)

Uwe Ligges


> Thanks
>
> -----
> Thanks in Advance
>          Arun
> --
> View this message in context:
http://r.789695.n4.nabble.com/calling-the-function-which-is-stored-in-a-list-tp4372131p4372131.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> R-help at r-project.org 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.

Thanks it works

-----
Thanks in Advance
        Arun
--
View this message in context:
http://r.789695.n4.nabble.com/calling-the-function-which-is-stored-in-a-list-tp4372131p4372557.html
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On Thu, Feb 9, 2012 at 2:54 AM, arunkumar1111 <akpbond007 at gmail.com>
wrote:
> Hi
>
> I'm storing two functions in a list
>
> # creating two function
> ?function1 <- function(n) {
> ?return(sum(n))
> }
>
> function2 <- function(n) {
> ?return(mean(n))
> }
>
> #storing the function
> function3 =c(function1,function2)
>
> is it possible to call the stored function and used it ?
>
> ?x=c(10,29)
> funtion3[1](x)
>
In addition to [[ as in the other response also try this:

L <- list(function1 = sum, function2 = mean)
L$function1(1:3)


Note that the proto package is somewhat similar but stores functions
in environments rather than lists and also supports a type of object
oriented programming:

library(proto)

p <- proto(function1 = function(., n) sum(n),
  function2 = function(., n) mean(n),
  function3 = function(.) mean(.$x),
  x = 1:10
)

p$function1(1:3)
p$function3() # mean of 1:10
p$x <- 1:5
p$function3() # mean of 1:5

# define child p2 with its own x overriding p's x
p2 <- p$proto(x = 10:15)

# p2 has its own x so this is mean of 10:15
# p2 inherits its methods from p so its has a
#   function3 too
p2$function3()

p$function3() # p unchanged. Still mean of 1:5.



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