Usage
legend(x, y = NULL, legend, fill = NULL, col = par("col"), lty, lwd, pch, angle = 45, density = NULL, bty = "o", bg = par("bg"), pt.bg = NA, cex = 1, pt.cex = cex, pt.lwd = lwd, xjust = 0, yjust = 1, x.intersp = 1, y.intersp = 1, adj = c(0, 0.5), text.width = NULL, text.col = par("col"), merge = do.lines && has.pch, trace = FALSE, plot = TRUE, ncol = 1, horiz = FALSE, title = NULL, inset = 0, border.col = NULL, border.lwd = 1, border.lty = "solid", box.col = NULL, box.lwd = 1, box.lty = "solid")
Arguments
x,y
the x and y co-ordinates to be used to position the legend. They
can be specified by keyword or in any way which is accepted by
xy.coords: See Details. legend
a character or expression vector. of length $>= 1$ to appear in the legend. fill
if specified, this argument will cause boxes filled with the
specified colors (or shaded in the specified colors) to appear beside the
legend text.
col
the color of points or lines appearing in the legend.
lty,lwd
the line types and widths for lines appearing in the legend.
One of these two must be specified for line drawing.
pch
the plotting symbols appearing in the legend, either as vector of
1-character strings, or one (multi character) string. Must be
specified for symbol drawing.
angle
angle of shading lines.
density
the density of shading lines, if numeric and positive. If
NULL or negative or NA color filling is assumed.
bty
the type of box to be drawn around the legend. The allowed
values are "o" (the default) and "n".
bg
the background color for the legend box. (Note that this is only
used if bty != "n".)
pt.bg
the background color for the points,
corresponding to its argument bg. cex
character expansion factor relative to current
par("cex").
pt.cex
expansion factor(s) for the points.
pt.lwd
line width for the points, defaults to the one for lines, or
if that is not set, to par("lwd").
xjust
how the legend is to be justified relative to the legend x
location. A value of 0 means left justified, 0.5 means centered and 1 means
right justified.
yjust
the same as xjust for the legend y location.
x.intersp
character interspacing factor for horizontal (x) spacing.
y.intersp
the same for vertical (y) line distances.
adj
numeric of length 1 or 2; the string adjustment for legend text.
Useful for y-adjustment when labels are plotmath expressions. text.width
the width of the legend text in x ("user")
coordinates. (Should be positive even for a reversed x axis.) Defaults to
the proper value computed by strwidth(legend). text.col
the color used for the legend text.
merge
logical; if TRUE, “merge” points and lines but
not filled boxes. Defaults to TRUE if there are points and lines.
trace
logical; if TRUE, shows how legend does all its
magical computations.
plot
logical. If FALSE, nothing is plotted but the sizes are
returned.
ncol
the number of columns in which to set the legend items (default
is 1, a vertical legend).
horiz
logical; if TRUE, set the legend horizontally rather
than vertically (specifying horiz overrides the ncol
specification).
title
a character string or length-one expression giving a title to
be placed at the top of the legend.
inset
inset distance(s) from the margins as a fraction of the plot
region when legend is placed by keyword.
border.lty,border.lwd
the line type and width for the legend border.
box.lty,box.lwd
the line type and width for the legend box.