title {graphics}R Documentation

Plot Annotation


This function can be used to add labels to a plot. Its first four principal arguments can also be used as arguments in most high-level plotting functions. They must be of type character or expression. In the latter case, quite a bit of mathematical notation is available such as sub- and superscripts, greek letters, fractions, etc.


title(main = NULL, sub = NULL, xlab = NULL, ylab = NULL,
      line = NA, outer = FALSE, ...)


main The main title (on top) using font and size (character expansion) par("font.main") and color par("col.main").
sub Sub-title (at bottom) using font and size par("font.sub") and color par("col.sub").
xlab X axis label using font and character expansion par("font.axis") and color par("col.axis").
ylab Y axis label, same font attributes as xlab.
line specifying a value for line overrides the default placement of labels, and places them this many lines from the plot.
outer a logical value. If TRUE, the titles are placed in the outer margins of the plot.
... further graphical parameters from par. Use e.g., col.main or cex.sub instead of just col or cex.


The labels passed to title can be simple strings or expressions, or they can be a list containing the string to be plotted, and a selection of the optional modifying graphical parameters cex=, col=, font=.


Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.

See Also

mtext, text; plotmath for details on mathematical annotation.


plot(cars, main = "") # here, could use main directly
title(main = "Stopping Distance versus Speed")

plot(cars, main = "")
title(main = list("Stopping Distance versus Speed", cex=1.5,
                  col="red", font=3))

## Specifying "..." :
plot(1, col.axis = "sky blue", col.lab = "thistle")
title("Main Title", sub = "sub title",
      cex.main = 2,   font.main= 4, col.main= "blue",
      cex.sub = 0.75, font.sub = 3, col.sub = "red")

x <- seq(-4, 4, len = 101)
y <- cbind(sin(x), cos(x))
matplot(x, y, type = "l", xaxt = "n",
        main = expression(paste(plain(sin) * phi, "  and  ",
                                plain(cos) * phi)),
        ylab = expression("sin" * phi, "cos" * phi), # only 1st is taken
        xlab = expression(paste("Phase Angle ", phi)),
        col.main = "blue")
axis(1, at = c(-pi, -pi/2, 0, pi/2, pi),
     lab = expression(-pi, -pi/2, 0, pi/2, pi))
abline(h = 0, v = pi/2 * c(-1,1), lty = 2, lwd = .1, col = "gray70")

[Package graphics version 2.1.0 Index]