[R] trellis: conditional statements within a panel function

[Deepayan Sarkar]

On 10/31/08, erwann rogard <erwann.rogard at gmail.com> wrote:
> hello,
>
>  what i'm trying to achieve is shown in the comment (# ...) below, which is
>  surely very wrong, but probably intuitively more meaningful that i can
>  provide in words.
>
>  xyplot(y~x2|x1+which,data=make.groups(
>   "a"=data.a,
>   "b"=data.b,
>   "c"=data.c
>   ),
>   panel=function(...){
>   panel.abline(a=0,b=0)
>   panel.points(...)
>   # if(x1==0 & which=="a") panel.abline(...)
>   },
>   layout=c(2,3),
>   pch=20,
>   ylim=c(-10,10),
>   xlab="x2",
>   cex=0.5
>  )

Check ?which.packet.

-Deepayan