[R] Question about adding text to xYplot(Hmisc)

[Deepayan Sarkar]

On 5/29/08, Wen Huang <whuang.ustc at gmail.com> wrote:
> Hello,
>
>  I have been trying to make a graph that have error bars and text at
> specific position.
>
>  I used the following code from the help file of xYplot(Hmisc) as an example
> except I add a myPanel function, which is just supposed to add letters from
> the alphabet at the position aligned at y = 3.
>
>  It constantly gives me error:
>  "Error using packet 1 argument "subscripts" is missing, with no default".
>
>  The same code can work with xyplot from the lattice package (does not have
> error bar though).
>
>  Can somebody kindly offer some help?
>
>  Thanks,
>  Wen
>  dfr <- expand.grid(month=1:12, continent=c('Europe','USA'),
>                    sex=c('female','male'))
>  set.seed(1)
>  dfr <- upData(dfr,
>               y=month/10 + 1*(sex=='female') + 2*(continent=='Europe') +
>                 runif(48,-.15,.15),
>               lower=y - runif(48,.05,.15),
>               upper=y + runif(48,.05,.15))
>
>  myPanel <- function(x, y, subscripts, ...) {
>   panel.xYplot(x, y, ...)
>   ltext(x, 3, letters[subscripts], cex=0.5)
>   }
>  xYplot(Cbind(y,lower,upper) ~ month,subset=sex=='male' & continent=='USA',
>        data=dfr, panel = myPanel)

panel.xYplot also wants subscripts, which you are not supplying. This
seems to work:

 myPanel = function(x, y, subscripts, ...) {
  panel.xYplot(x, y, subscripts = subscripts, ...)
  ltext(x, 3, letters[subscripts], cex=0.5)
  }

-Deepayan