Hi Kieran, I'm not very familiar with lattice, but here's a workaround that works for me. Basically, I just created a new data.frame column that was a factor (combo$zf), and forced its levels to be what you're looking for here.
require(lattice) x<-c(1,2,3) y<-c(2,4,6) z<-c(0.1,0.5,2) combo<-expand.grid(x,y,z) combo<-data.frame(combo) names(combo)<-c("x","y","z") outcome<-function(l) { (l[1]*l[2])/l[3] } resp<-apply(combo,1,outcome) ## Create new column and assign levels combo$zf <- as.factor(combo$z) levels(combo$zf) <- paste("z=", levels(combo$zf), sep="") ## Now I use the new variable as the conditioning variable in the plot levelplot(resp~x*y|zf, data=combo ,pretty=TRUE,region=TRUE,contour=FALSE) In the future, it would help if you could specify the packages you're using, since I had to do a little research to find where the "levelplot" function is from. Hope this helps, Ethan On Tue, Jun 7, 2011 at 9:30 AM, kieran martin <kieranjmar...@gmail.com>wrote: > Hi, > > I've been driving myself insane with this problem. I have a trellis plot of > contours, and I want each level to have something like "z=value" for each > one. I can get each one to say z, or each one to say the value (by using > as.factor) but not both. Heres an artificial example to show what I mean > (as > my actual data set is much larger!) > > x<-c(1,2,3) > y<-c(2,4,6) > z<-c(0.1,0.5,2) > combo<-expand.grid(x,y,z) > combo<-data.frame(combo) > names(combo)<-c("x","y","z") > outcome<-function(l) > { > (l[1]*l[2])/l[3] > } > resp<-apply(combo,1,outcome) > levelplot(resp~x*y|z,data=combo > ,pretty=TRUE,region=TRUE,contour=FALSE) > > , so in this final graph I want the z=0.1, z=0.5 and z=2 in turn. > > Thanks, > > Kieran Martin > University of Southampton > > [[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. > [[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.