Extracting specified pages from a lattice ("trellis") object.
Suppose that (e.g.) xyplot() returns an object "xxx" with (say) 3 pages.
I would like to extract/plot (print) just one of these pages, e.g.
Here's a toy example:
x <- rep(seq(0,1,length=11),12)
y <- rnorm(3*44)
a <- rep(letters[1:12],each=11)
dta <- data.frame(x=x,y=y,a=a)
xxx <- xyplot(y~x|a,data=dta,layout=c(2,2))
I would to extract from xxx and print page 2 (the page corresponding to
levels e, f, g and h).
Is there any (simple) way that I can do this?
I've mucked around with update.trellis() and [.trellis, but I cannot
make head nor tail of the documentation. The [.trellis method seems to
work in some situations, but not in others, and since I cannot
understand what it actually does, I cannot figure out why.
E.g. in my toy example "xxx[5:8]" seems to give me what I want, but in
the context of my real application a similar construction does not work.
Thanks for any insight.
Technical Editor ANZJS
Department of Statistics
University of Auckland
Phone: +64-9-373-7599 ext. 88276