Hi r-help-boun...@r-project.org napsal dne 20.02.2009 10:34:02:
> > > Hi, > > I want to add a dashed vertical line to a number of xyplots. > > Here is a simple script of the type of plot I have but then I want to add a > reference line to 1995 on each of the panels. I have tried panel.abline and > other suggestions on the forum but can't get it to work. > > plot<-rep(letters[1:3],each=10) > year<-rep(1991:2000,times=3) > matter<-rep(seq(2,6.5,0.5),times=3) > xyplot(matter~year|plot,type="l") Here is a function which I adapted from Gabor Grothendieck's suggestion addLine<- function(a=NULL, b=NULL, v = NULL, h = NULL, ..., once=F) { tcL <- trellis.currentLayout() k<-0 for(i in 1:nrow(tcL)) for(j in 1:ncol(tcL)) if (tcL[i,j] > 0) { k<-k+1 trellis.focus("panel", j, i, highlight = FALSE) if (once) panel.abline(a=a[k], b=b[k], v=v[k], h=h[k], ...) else panel.abline(a=a, b=b, v=v, h=h, ...) trellis.unfocus() } } It works on plotted xyplot, accepts single value or vector of values which can be different for each panel. Regards Petr > > Cheers, > Chris > -- > View this message in context: http://www.nabble.com/adding-a-reference-line- > to-an-xyplot-tp22117545p22117545.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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. ______________________________________________ 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.