points {base} | R Documentation |
points
is a generic function to draw a sequence of points at
the specified coordinates. The specified character(s) are plotted,
centered at the coordinates.
points(x, ...) points.default(x, y=NULL, type="p", pch=par("pch"), col=par("col"), bg=NA, cex=1, ...)
x, y |
coordinate vectors of points to plot. |
type |
character indicating the type of plotting; actually any of
the type s as in plot . |
pch |
plotting ``character'', i.e. symbol to use. pch can
either be a character or an integer code for a set of
graphics symbols. The full set of S symbols is available with
pch=0:18 , see the last picture from example(points) ,
i.e., the examples below.
In addition, there is a special set of R plotting symbols which can be obtained with pch=19:25 and 21:25 can be
colored and filled with different colors:
|
col |
color code or name, see par . |
bg |
background (``fill'') color for open plot symbols |
cex |
character expansion |
... |
Further graphical parameters (see plot.xy
and par ) may also be supplied as arguments. |
The coordinates can be passed in a plotting structure
(a list with x
and y
components), a two-column matrix, a
time series, .... See xy.coords
.
Graphical parameters are permitted as arguments to this function.
plot
, lines
, and the underlying
``primitive'' plot.xy
.
plot(-4:4, -4:4, type = "n")# setting up coord. system points(rnorm(200), rnorm(200), col = "red") points(rnorm(100)/2, rnorm(100)/2, col = "blue", cex = 1.5) op <- par(bg = "light blue") x <- seq(0,2*pi, len=51) ## something ``between type="b" and type="o" '' : plot(x, sin(x), type="o", pch=21, bg=par("bg"), col = "blue", cex=.6, main='plot(..., type="o", pch=21, bg=par("bg"))') par(op) ##-------- Showing all the extra & some char graphics symbols ------------ Pex <- 3 ## good for both .Device=="postscript" and "x11" ipch <- 1:(np <- 25+11); k <- floor(sqrt(np)); dd <- c(-1,1)/2 rx <- dd + range(ix <- (ipch-1) %/% k) ry <- dd + range(iy <- 3 + (k-1)-(ipch-1) %% k) pch <- as.list(ipch) pch[25+ 1:11] <- as.list(c("*",".", "o","O","0","+","-",":","|","%","#")) plot(rx, ry, type="n", axes = FALSE, xlab = "", ylab = "", main = paste("plot symbols : points (... pch = *, cex =", Pex,")")) abline(v = ix, h = iy, col = "lightgray", lty = "dotted") for(i in 1:np) { pc <- pch[[i]] points(ix[i], iy[i], pch = pc, col = "red", bg = "yellow", cex = Pex) ## red symbols with a yellow interior (where available) text(ix[i] - .3, iy[i], pc, col = "brown", cex = 1.2) }