Dear all , Thank you for the replies. The idea of plotting back on top of the grid was the right direction and after browsing and browsing I found a tip in the R archive ([R] How to get a grid behind a boxplot) by Neuro LeSuperHéros which uses par(new=T):
x<-rnorm(100) boxplot(x) abline(h=c(-1,0,1)) grid(NA, 4, lwd = 2) par(new=TRUE) boxplot(x, col="white") best wishes, Luigi ______________________________________________ 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.
