n.plot: Name Plot: Names or Numbers instead of Points in Plot

Description

A utility function which basically calls plot(*, type="n") and text. To have names or numbers instead of points in a plot is useful for identifaction, e.g., in a residual plot, see also TA.plot.

Usage

n.plot(x, y = NULL, nam = NULL, abbr = n >= 20 || max(nchar(nam))>=8,
       xlab = NULL, ylab = NULL, log = "",
       cex = par("cex"), col = par("col"), ...)

Value

invisibly, a character vector with the labels used.

Arguments

x,y: coordinates at which to plot. If y is missing, x is used for both, if it's a data.frame, list, 2-column matrix etc -- via xy.coords; formula do not work.
nam: the labels to plot at each (x,y). Per default, these taken from the data x and y; case numbers 1:n are taken if no names are available.
abbr: logical indicating if the nam labels should be abbreviated -- with a sensible default.
xlab,ylab: labels for the x- and y- axis, the latter being empty by default.
log: character specifying if log scaled axes should be used, see plot.default.
cex: plotting character expansion, see par.
col: color to use for text().
...: further arguments to be passed to the plot call.

Author

Martin Maechler, since 1992

Examples

Run this code

 n.plot(1:20, cumsum(rnorm(20)))
 data(cars)
 with(cars, n.plot(speed, dist, cex = 0.8, col = "forest green"))