Thanks for the reply. Trunc would only work when the truncated y values result in the desired y coordinates for the grid lines as in this simple data set. Since my real dataset contains many more points, it does not give a general solution.
Rene -----Original Message----- From: Bernd Weiss [mailto:[EMAIL PROTECTED] Sent: Tuesday, February 20, 2007 9:44 PM To: Rene Braeckman; r-help@stat.math.ethz.ch Subject: Re: [R] Different gridlines per panel in xyplot Am 20 Feb 2007 um 20:52 hat Rene Braeckman geschrieben: From: "Rene Braeckman" <[EMAIL PROTECTED]> To: <r-help@stat.math.ethz.ch> Date sent: Tue, 20 Feb 2007 20:52:29 -0800 Subject: [R] Different gridlines per panel in xyplot > In the example R script below, horizontal gray gridlines are drawn at > y coordinates where the points are drawn with the code: > > panel.abline(h=y, v=xScale, col.line="gray") > > How do I change this so that the horizontal gray gridlines are drawn > at y coordinates where the y labels are drawn? The challenge is that > each panel has different y-ranges (in my real example the y-ranges and > y-intervals are even more different). For example, I wish I could use > the yScale list as the h parameter in abline, but it does not work > with a list. > > Thanks for any help. > Rene > > library(lattice) > Subj <- rep(1:4,each=3) > Time <- rep(1:3,4) + 0.1 > Conc <- (1:12) + 0.1 > df <- data.frame(Subj,Time,Conc) > xScale <- 1:3 > yScale <- list(1:3,4:6,7:9,10:12) > xyplot(Conc ~ Time | Subj, > data = df, > layout = c(2,2), > type="b", > scales=list( > x=list(at=xScale), > y=list(at=yScale,relation="free") > ), > panel = function(x,y,...) { > panel.abline(h=y, v=xScale, col.line="gray") > panel.xyplot(x,y,...) > } > ) > Dear Rene, I am not quite sure whether this is the most elegant/general solution, but one option might be to use trunc(), see the full code below. panel.abline(h=trunc(y), v=xScale, col.line="gray") library(lattice) Subj <- rep(1:4,each=3) Time <- rep(1:3,4) + 0.1 Conc <- (1:12) + 0.1 df <- data.frame(Subj,Time,Conc) xScale <- 1:3 yScale <- list(1:3,4:6,7:9,10:12) xyplot(Conc ~ Time | Subj, data = df, layout = c(2,2), type="b", scales=list( x=list(at=xScale), y=list(at=yScale,relation="free") ), panel = function(x,y,...) { ## use trunc(y) panel.abline(h=trunc(y), v=xScale, col.line="gray") panel.xyplot(x,y,...) } ) HTH, Bernd ______________________________________________ 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.
