[R] R function returning a list of variable(s) conditional on the value of an option?

[PIKAL Petr]

Hi

It is not exactly clear what do you want from your function.

foo <- function(x, y, option = TRUE)

in that cese you want to return list
x,y,z or x,y,z,w with w=NA

the same apply with
foo <- function(x, y, option = FALSE)

return is
x,y,w or x,y,z=NA,w?

anyway I would use option like that

{
x=x
y=y
z=NA
w=NA

if (option == TRUE) {

                z = z
return(x,y,z,w)
        } else {
                w = w
return(x,y,z,w)
}
}


Maybe different approach can be used but without clear description of objects x,y,z,w it is difficult to be more specific.

Regards
Petr


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Luke Hartigan
> Sent: Friday, July 25, 2014 2:23 PM
> To: r-help at r-project.org
> Subject: [R] R function returning a list of variable(s) conditional on
> the value of an option?
>
> Dear all,
>
> I have an R function which returns a list of variables; however, within
> the body of the function I would like to incorporate a branch based on
> a user selected option that will mean there will be one different
> variable to return based on the option value.
>
> I was thinking of doing something like this (only an example):
>
> foo <- function(x, y, option = TRUE)
> {
>       .
>       If (option == TRUE) {
>               z = z
>       } else {
>               w = w
> }
>       return(list(x = x, y = y, z = ifelse(option == TRUE, z, NA), w =
> ifelse(option != TRUE, w, NA))
>
> }
>
> However, I was wondering if anyone else had a better idea/method which
> might be more elegant?
>
> Many thanks,
> Luke
>
>
>
>       [[alternative HTML version deleted]]
>
> ______________________________________________
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> and provide commented, minimal, self-contained, reproducible code.

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