Setting par(usr=something) does not survive the creating of a new high level plot. Using par(new=TRUE) is to be avoided if at all possible (it just leads to problems like yours), it would be better for you to use matlines instead of matplot which adds lines to the current plot.
If you want to set the limits for a new plot to exactly match the previous one use the xlim argument along with xaxs='i' (or an additional buffer will be added again). If you really need to adjust the range of one of the axes to combine the plots (not recommended, this can cause confusion and emphasize meaningless crossings, it is better to juxtapose two aligned plots) then consider using the updateusr function in the TeachingDemos package. -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.s...@imail.org 801.408.8111 > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-bounces@r- > project.org] On Behalf Of gerald.j...@dgag.ca > Sent: Monday, September 12, 2011 1:34 PM > To: r-h...@stat.math.ethz.ch > Subject: [R] Centering lines on barplot centers. > > > Hello, > > I am trying to port one of my plotting S+ functions to R and I am > having > difficulties!!! I am including here only the troublesome code! > > I first produce a barplot, saving the positions of the bar's centers. > > par(mar = c(6.1, 5.1, 4.1, 4.1), mgp = c(3, 3.0, 0)) > ticks.loc <- barplot(sum.of.weights, col = 5, xlab = "", ylab = "", > axes = FALSE, axisnames = FALSE) > pretty.bar <-pretty(c(0, sum.of.weights), 6) > pretty.lab <- paste(pretty.bar, "%", sep = "") > axis(side = 2, at = pretty.bar, labels = pretty.lab, col = 1, line = > 0, > cex.axis = 0.80, las = 2, mgp = c(3, 2, 0)) > my.axis(side = 1, at = ticks.loc, labels = plot.labels, > las = 2, col = 1, adj = 1, cex.axis = labels.cex, mgp = c(2, > 1, > 0)) > box() > title(main = titre, cex = title.cex) > > Then I would like to plot three lines with the x-positions of the > points on > the bar's centers. In S+ I use "par(new = TRUE, xaxs = "d")", which > freezes the "x-axis" and that does the trick. In R this option is not > supported, I tried to play with the user-coordinates, using the same > ones > from one plot to the other but there is a slight offset in the location > of > the points w.r. to the centers of the bar??? > > user.corr <- par("usr") > par(new = TRUE, mar = c(6.1, 5.1, 4.1, 4.1), mgp = c(3, 3.0, 0), > usr = user.corr) > matplot(x = ticks.loc, > y = observed.means[, c("observed", "rebal.old", > "rebal.new")], > type = "b", lwd = 1.0, cex = 0.80, xlab = "", ylab = "", > axes = FALSE) > pretty.bar <- pretty(c(0, max(observed.means[, c("observed", > "rebal.old", > "rebal.new")]))) > axis(side = 4, at = pretty.bar, line = 0, mgp = c(2, 2, 0), las = 2, > col.axis = 1, cex.axis = 0.80) > > Any suggestions??? Thanks in advance, > > Gérald Jean > Conseiller senior en statistiques, > VP Actuariat et Solutions d'assurances, > Desjardins Groupe d'Assurances Générales > télephone : (418) 835-4900 poste (7639) > télecopieur : (418) 835-6657 > courrier électronique: gerald.j...@dgag.ca > ______________________________________________ > 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.
