[R] S4 classes?

[Uwe Ligges]

Spencer Graves wrote:

>      The following example, extracted from pp. 38-42 of Chambers (1998) 
> Programming with Data (Springer), works for me in S-Plus 6.2 but not R 
> 1.9.0pat, which returns the indicated error messages:
>  > setClass('track', representation(x="numeric", y="numeric"))
> [1] "track"
>  > tr1 <- new("track", x=1:3, y=4:6)
>  > setMethod("plot",
> + signature(x="track", y="missing"),
> + function(x, y, ...)plot(x at x, x at y, ...)
> + )
> [1] "plot"
>  > plot(tr1)
> Error in plot.window(xlim, ylim, log, asp, ...) :
>        need finite xlim values
> In addition: Warning messages:
> 1: no finite arguments to min; returning Inf
> 2: no finite arguments to max; returning -Inf
> 3: no finite arguments to min; returning Inf
> 4: no finite arguments to max; returning -Inf
> 
>      Am I missing something or is my copy of R 1.9.0pat corrupted?  
> (This is under Windows 2000.)
>      Thanks Much!
>      Spencer Graves


Works for me with R-1.9.0 Patched (2004-05-24)

Uwe