Demo of plotrix

library(plotrix)

y <- runif(10)
err <- runif(10)
plotCI(1:10, y, err, main = "Basic plotCI")

plotCI(1:10, y, err, 2 * err, lwd = 2, col = "red", scol = "blue", main = "Add colors to the points and error bars")

err.x <- runif(10)
err.y <- runif(10)
plotCI(1:10, y, err.y, pt.bg = par("bg"), pch = 21, xlim = c(0, 11), main = "plotCI with extra space on the x axis")
plotCI(1:10, y, err.x, pt.bg = par("bg"), pch = 21, err = "x", add = TRUE)
mtext("for adding horizontal error bars", 3, 0.5)

data(warpbreaks)
attach(warpbreaks)
wmeans <- by(breaks, tension, mean)
wsd <- by(breaks, tension, sd)
## note that barplot() returns the midpoints of the bars, which plotCI
## uses as x-coordinates
plotCI(barplot(wmeans, col = "gray", ylim = c(0, max(wmeans + wsd))), wmeans, 
    wsd, add = TRUE)

## using labels instead of points
labs <- sample(LETTERS, replace = TRUE, size = 10)
plotCI(1:10, y, err, pch = NA, gap = 0.02, main = "plotCI with labels at points")
text(1:10, y, labs)