| plot.window {base} | R Documentation |
This function sets up the world coordinate system for a graphics
window. It is called by higher level functions such as
plot.default (after plot.new).
plot.window(xlim, ylim, log = "", asp = NA, ...)
xlim, ylim |
numeric of length 2, giving the x and y coordinates ranges. |
log |
character; indicating which axes should be in log scale. |
asp |
numeric, giving the aspect ratio y/x. |
... |
further graphical parameters as in par(..). |
Note that if asp is a finite positive value then
the window is set up so that one data unit in the x direction
is equal in length to asp * one data unit in the
y direction.
The special case asp == 1 produces plots where distances
between points are represented accurately on screen. Values
with asp > 1 can be used to produce more accurate maps when
using latitude and longitude.
Usually, one should rather use the higher level functions such as
plot, hist, image, ...,
instead and refer to their help pages for explanation of the arguments.
xy.coords, plot.xy, plot.default.
##--- An example for the use of `asp' :
library(mva)
data(eurodist)
loc <- cmdscale(eurodist)
rx <- range(x <- loc[,1])
ry <- range(y <- -loc[,2])
plot(x, y, type="n", asp=1, xlab="", ylab="")
abline(h=pretty(rx, 10),
v=pretty(ry, 10), col= "lightgray")
text(x, y, names(eurodist), cex=0.5)