The example code below allows the plotting of three different groups per panel. I can't fathom how to write the panel function to add an additional line for each group, which in this case is just the mean Y value for each group within each panel. (i.e. there'd be six lines per panel.) Spent all day working on it and searching the archives to no avail! Yikes. Any help would be greatly appreciated! Michael Folkes
#________________________ #This builds fake dataset years<-2000:2006 weeks<-1:20 yr<-rep(years,rep(length(weeks)*6,length(years))) wk<-rep(weeks,rep(6,length(weeks))) temp<-rep(4:9,length(years)*length(weeks)) yvar<-round(rnorm(length(years)*length(weeks)*6,mean=30,sd=4),0) xvar<-(rnorm(length(years)*length(weeks)*6)+5)/10 df<-data.frame(year=yr,week=wk,temp=temp, yvar=yvar, xvar=xvar) #________________________ library(lattice) df$year2<-as.factor(df$year) df$week2<-as.factor(df$week) df<-df[df$temp %in% c(5,7,9),] xyplot(yvar~year|week2,data=df,layout = c(4, 5), as.table=TRUE, type='l', groups=temp , panel = function(x, y,groups, ...) { panel.superpose(x,y,groups,...) panel.xyplot(x,rep(mean(y),length(x)),type='l',lty=3) #<- only generates the panel mean } ) _______________________________________________________ Michael Folkes Salmon Stock Assessment Canadian Dept. of Fisheries & Oceans Pacific Biological Station 3190 Hammond Bay Rd. Nanaimo, B.C., Canada V9T-6N7 Ph (250) 756-7264 Fax (250) 756-7053 [EMAIL PROTECTED] [[alternative HTML version deleted]] ______________________________________________ R-help@stat.math.ethz.ch 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.