[R] multi-argument returns

[Prof Brian Ripley]

On Wed, 17 Feb 2010, Randall Wrong wrote:

> Dear R users,
>
> I have multi-argument returns in a function and I am warned by the program
> they are deprecated.

Defunct as from the next R release.

> I have found this in the R-help archives :

in 2001!

> http://tolstoy.newcastle.edu.au/R/help/01c/0319.html
> http://tolstoy.newcastle.edu.au/R/help/01c/0356.html
>
> Since I am not too good at programming, the list solution seems the better
> one for me. It is also the one advocated by Kevin Murphy.
>
> So rather than writing return(x,y,z), I should write at the end of my
> function :

return(list(x=x,y=y,z=z)) is the preferred replacement.
(As the help page for return() has long said.)

> g=function() {
>
>    #...
>
>    result=list(x,y,z)
>    return(result)
> }
>
> Is that correct ?
>
> Then shoud l use g[1] or g[[1]] ?

No change is needed (I think you mean g()$x etc) as return(x,y,z) and 
return(list(x=x,y=y,z=z)) are identical in their effects.

> Thank you for you help.
>
> Randall

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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