R: Plot Annotation

title {base}

R Documentation

Plot Annotation

Description

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.

Usage

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

Arguments

`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`).

Details

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=.

Examples

data(cars)
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))

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")