hello, what i'm trying to achieve is shown in the comment (# ...) below, which is surely very wrong, but probably intuitively more meaningful that i can provide in words.
xyplot(y~x2|x1+which,data=make.groups( "a"=data.a, "b"=data.b, "c"=data.c ), panel=function(...){ panel.abline(a=0,b=0) panel.points(...) # if(x1==0 & which=="a") panel.abline(...) }, layout=c(2,3), pch=20, ylim=c(-10,10), xlab="x2", cex=0.5 ) thank! [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.