[R] Varying grid.rect in different panels of a Lattice plot
Leon Barmuta
Leon.Barmuta at utas.edu.au
Thu Mar 17 01:48:37 CET 2005
Dear r-help,
Sleep-deprivation from having 2 youngsters under 2 around the house is
fuzzing my brain, so please be gentle if the answer to this query is obvious!
In the example below, I'm trying to use grid.rect to add grey rectangles to
the panels of a lattice plot to indicate which months spawning occurred of
a (very cute) native Tasmanian fish. The fish in the two lakes spawned at
slightly different times, so grid.rect needs to be conditioned on when
spawning happened in each lake. However, the panel function I wrote first,
and reproduce below, inserts grey rectangles for all dates that spawning
occured pooled across the two lakes. So after dreging r-help, I've messed
with subscripts and tried fiddling with panel.number, but can't get this to
work. Any suggestions most welcome!
# Make up a short data set
library(lattice)
library(grid)
Lake <- rep(c("Crescent","Sorell"), each=13)
Spawning <- c("Y", rep("N",7), rep("Y",4), rep("N",8), rep("Y",5), "N")
Catch <- rpois(26, 30) # fake data
Plotdate <- rep(seq(as.Date("2000/10/1"), by="month", length=13),2)
trellis.device(theme=col.whitebg())
# panel function that doesn't quite work
myPanel <- function(x, y, ...) {
grid.rect(x=unit(Plotdate[Spawning == "Y"], "native"),
just="left", width=unit(31, "native"), # a bit of a fudge
gp=gpar(col="transparent", fill="light grey"))
panel.xyplot(x, y, ...)}
xyplot(Catch ~ Plotdate|Lake, type="b",
panel=myPanel,
layout=c(1,2), xlab="",
scales = list(x=list(rot = 45, at=as.numeric(Plotdate),
labels=format(Plotdate, "%b%Y"))))
Regards,
Leon
-------------------------
Dr Leon A. Barmuta, Senior Lecturer in Zoology
School of Zoology & TAFI, University of Tasmania, Private Bag 5, Hobart,
Tasmania 7001, Australia
Phone (03) 6226 2785; Fax (03) 6226 2745; International callers replace
(03) with +61 3
School of Zoology web page: http://www.scieng.utas.edu.au/zoo/
My web page: http://www.scieng.utas.edu.au/zoo/pagedetails.asp?lpersonId=222
More information about the R-help
mailing list