[R] lattice: How to specify strip text in an xyplot?

[Marius Hofert]

Hi,

How can I specify the strip text in the xyplot below?
I also tried to work with strip.names=c("TRUE","TRUE"), but that did not work.

Cheers,

Marius

library(lattice)
x <- 1:10
y <- cbind(1:10,-(1:10)) 

xyplot(y[,1]+y[,2]~x,outer=TRUE,strip=function(var.name,...) 
	strip.default(var.name=c("plot 1","plot 2"),...))