[R] Minor Tick Marks in Lattice

[Rene Braeckman]

I have a couple if issues with the code below.

1. as.Table=TRUE has no effect
2. the minor tick marks on top of the top panels are drawn in the strips and
not on the axes.

Any ideas what's wrong? There are probably better ways to add minor tick
marks...
Thanks for any help.
Rene

--------------------------------  
 
library(lattice)
Subj <- paste("Subj", rep(1:4,each=3))
Time <- rep(1:3,4) + 0.1
Conc <- (1:12) + 0.1
df <- data.frame(Subj,Time,Conc)
xScale <- 1:3
yScale <- list(1:3,4:6,7:9,10:12)
xMinorTicks <- seq(0.5,2.5,0.5)
 
xyplot(Conc ~ Time | Subj,
       data = df,
       layout = c(2,2),
       type="b",
       as.Table=TRUE,
       scales=list(
          x=list(at=xScale),
          y=list(at=yScale,relation="free"),
          alternating=3
       ),
       panel = function(x,y,...) {
          panel.abline(h=yScale[[panel.number()]], v=xScale,
col.line="gray")
          panel.xyplot(x,y,...)             
      }
)
 
# Add minor tick marks on bottom or top
for (coli in 1:2) {
  for (rowi in 1:2) {
    trellis.focus(name="panel", column=coli, row=rowi, clip.off = TRUE) 
    panel.axis(ifelse(rowi==1,"bottom","top"), 
      check.overlap = TRUE, outside = TRUE, labels = FALSE, 
      tck = .5, at = xMinorTicks)  
    trellis.unfocus()
  }
}