You can edit the barplot function to do this: mybarplot <- function (height, width = 1, space = NULL, names.arg = NULL, legend.text = NULL, beside = FALSE, horiz = FALSE, density = NULL, angle = 45, col = NULL, border = par("fg"), main = NULL, sub = NULL, xlab = NULL, ylab = NULL, xlim = NULL, ylim = NULL, xpd = TRUE, log = "", axes = TRUE, axisnames = TRUE, cex.axis = par("cex.axis"), cex.names = par("cex.axis"), inside = TRUE, plot = TRUE, axis.lty = 0, offset = 0, add = FALSE, args.legend = NULL, ...) { if (!missing(inside)) .NotYetUsed("inside", error = FALSE) if (is.null(space)) space <- if (is.matrix(height) && beside) c(0, 1) else 0.2 space <- space * mean(width) if (plot && axisnames && is.null(names.arg)) names.arg <- if (is.matrix(height)) colnames(height) else names(height) if (is.vector(height) || (is.array(height) && (length(dim(height)) == 1))) { height <- cbind(height) beside <- TRUE if (is.null(col)) col <- "grey" } else if (is.matrix(height)) { if (is.null(col)) col <- grey.colors(nrow(height)) } else stop("'height' must be a vector or a matrix") if (is.logical(legend.text)) legend.text <- if (legend.text && is.matrix(height)) rownames(height) stopifnot(is.character(log)) logx <- logy <- FALSE if (log != "") { logx <- length(grep("x", log)) > 0L logy <- length(grep("y", log)) > 0L } if ((logx || logy) && !is.null(density)) stop("Cannot use shading lines in bars when log scale is used") NR <- nrow(height) NC <- ncol(height) if (beside) { if (length(space) == 2) space <- rep.int(c(space[2L], rep.int(space[1L], NR - 1)), NC) width <- rep(width, length.out = NR) } else { width <- rep(width, length.out = NC) } offset <- rep(as.vector(offset), length.out = length(width)) delta <- width/2 w.r <- cumsum(space + width) w.m <- w.r - delta w.l <- w.m - delta log.dat <- (logx && horiz) || (logy && !horiz) if (log.dat) { if (min(height + offset, na.rm = TRUE) <= 0) stop("log scale error: at least one 'height + offset' value <= 0") if (logx && !is.null(xlim) && min(xlim) <= 0) stop("log scale error: 'xlim' <= 0") if (logy && !is.null(ylim) && min(ylim) <= 0) stop("log scale error: 'ylim' <= 0") rectbase <- if (logy && !horiz && !is.null(ylim)) ylim[1L] else if (logx && horiz && !is.null(xlim)) xlim[1L] else 0.9 * min(height, na.rm = TRUE) } else rectbase <- 0 if (!beside) height <- rbind(rectbase, apply(height, 2L, cumsum)) rAdj <- offset + (if (log.dat) 0.9 * height else -0.01 * height) delta <- width/2 w.r <- cumsum(space + width) w.m <- w.r - delta w.l <- w.m - delta if (horiz) { if (is.null(xlim)) xlim <- range(rAdj, height + offset, na.rm = TRUE) if (is.null(ylim)) ylim <- c(min(w.l), max(w.r)) } else { if (is.null(xlim)) xlim <- c(min(w.l), max(w.r)) if (is.null(ylim)) ylim <- range(rAdj, height + offset, na.rm = TRUE) } if (beside) w.m <- matrix(w.m, ncol = NC) if (plot) { opar <- if (horiz) par(xaxs = "i", xpd = xpd) else par(yaxs = "i", xpd = xpd) on.exit(par(opar)) if (!add) { plot.new() plot.window(xlim, ylim, log = log, ...) } xyrect <- function(x1, y1, x2, y2, horizontal = TRUE, ...) { if (horizontal) rect(x1, y1, x2, y2, ...) else rect(y1, x1, y2, x2, ...) } if (beside) xyrect(rectbase + offset, w.l, c(height) + offset, w.r, horizontal = horiz, angle = angle, density = density, col = col, border = border) else { for (i in 1L:NC) { xyrect(height[1L:NR, i] + offset[i], w.l[i], height[-1, i] + offset[i], w.r[i], horizontal = horiz, angle = angle, density = density, col = col, border = border[ifelse(i > length(border), 1, i)]) ######## Line edited } } if (axisnames && !is.null(names.arg)) { at.l <- if (length(names.arg) != length(w.m)) { if (length(names.arg) == NC) colMeans(w.m) else stop("incorrect number of names") } else w.m axis(if (horiz) 2 else 1, at = at.l, labels = names.arg, lty = axis.lty, cex.axis = cex.names, ...) } if (!is.null(legend.text)) { legend.col <- rep(col, length.out = length(legend.text)) if ((horiz & beside) || (!horiz & !beside)) { legend.text <- rev(legend.text) legend.col <- rev(legend.col) density <- rev(density) angle <- rev(angle) } xy <- par("usr") if (is.null(args.legend)) { legend(xy[2L] - xinch(0.1), xy[4L] - yinch(0.1), legend = legend.text, angle = angle, density = density, fill = legend.col, xjust = 1, yjust = 1) } else { args.legend1 <- list(x = xy[2L] - xinch(0.1), y = xy[4L] - yinch(0.1), legend = legend.text, angle = angle, density = density, fill = legend.col, xjust = 1, yjust = 1) args.legend1[names(args.legend)] <- args.legend do.call("legend", args.legend1) } } title(main = main, sub = sub, xlab = xlab, ylab = ylab, ...) if (axes) axis(if (horiz) 1 else 2, cex.axis = cex.axis, ...) invisible(w.m) } else w.m }
mybarplot(matrix(1:6, ncol=3), border = c(NA, "red", NA)) On Tue, Jan 12, 2010 at 3:06 PM, RINNER Heinrich <heinrich.rin...@tirol.gv.at> wrote: > Dear R-users, > > I am using R version 2.10.1 under windows. > > In a barplot, I want to mark one of the bars with a special border color. > For example: > barplot(c(3, 7, 11), border = c(NA, "red", NA)) > > But how to do this when the bars are stacked? > for example: > barplot(matrix(1:6, ncol=3)) # border of second bar (i.e. the one with total > height = 7) should be red again, I try: > barplot(matrix(1:6, ncol=3), border = c(NA, "red", NA)) > > Obviously, this doesn't give me what I want. > Your advice would be appreciated; > kind regards > Heinrich. > > ______________________________________________ > 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. > -- Henrique Dallazuanna Curitiba-Paraná-Brasil 25° 25' 40" S 49° 16' 22" O ______________________________________________ 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.