[R] Plotting points on line graphs using xYplot in Hmisc

[Deepayan Sarkar]

On 5/5/08, John Poulsen <jpoulsen at ufl.edu> wrote:
>
>
>  Hello,
>
>  I am using xYplot to plot lines with confidence bands (see test example
> below).  I would like to add a single point with confidence bars to each
> graph (coordinates of the points below: px, py, pxlow, etc...).  I tried
> playing with panel=panel.superpose, but failed to get it to work.  Any ideas
> on how to add these points to the graphs?

If you want to add the same lines/points in all panels, you could
write a not-too-complicated custom panel function; e.g.,

with(dat,
     xYplot(Cbind(ycomb, y.up, y.low)~x1|factor(grp),
            data=dat,type="l",
            method="filled bands",
            col.fill="light grey",
            subscripts = TRUE,
            panel = function(...) {
                panel.xYplot(...)
                panel.segments(pxlow, pylow, pxhi, pyhi)
            },
            scales=
            list(y=list(relation="free"),
                 x=list(alternating=c(1,1,1))),
            ylim=list(c(0,1200),c(0,10000))))

-Deepayan