plot a Spatial Point Pattern
Plot a two-dimensional spatial point pattern
plot.ppp(x, main, ..., chars, cols, use.marks=TRUE, add=FALSE, maxsize)
- The spatial point pattern to be plotted.
An object of class
"ppp", or data which can be converted into this format by
- text to be displayed as a title above the plot.
- extra arguments that will be passed to the plotting functions
parfor possible options) or
- the plotting characters which should be used to represent the points of different types, in the case of a multitype point pattern.
- the colours which should be used to plot the points of different types, in the case of a multitype point pattern.
- logical flag; if
TRUE, plot points using a different plotting symbol for each mark; if
FALSE, only the locations of the points will be plotted, using
- logical flag; if
TRUE, just the points are plotted, over the existing plot. A new plot is not created, and the window is not plotted.
- the maximum radius of the circles plotted.
xis a marked point pattern with numerical marks, the marks are plotted as circles with maximum radius
maxsize(in the same units as the coordinates of the point
This is the
plot method for
point pattern datasets (of class
First the observation window
x$window is plotted
Then the locations of the points are plotted.
If the points do not have marks (i.e.
x$marks is absent)
use.marks = FALSE,
then the locations of the points will be plotted
using a single plot character. This character can be changed
by the extra argument
pch; see the examples.
For a marked point pattern (where
x$marks is not null)
each point will be represented by a graphical symbol plotted at the
location of the point.
The graphical representation of the marks depends
on their storage mode:
[object Object],[object Object],[object Object]
If the arguments
cols are supplied,
they should be vectors of the same length
sort(unique(x$marks)), and then the $i$th smallest mark
will be plotted using character
chars[i] and colour
cols is incompatible with
the generic plot argument
col. If both are given,
an error is generated and no plot is produced.
NULL, or a vector giving the correspondence between mark values and plotting characters.
data(cells) plot(cells) # multitype data(lansing) plot(lansing) # marked by a real number data(longleaf) plot(longleaf) # just plot the points plot(longleaf, use.marks=FALSE) plot(unmark(longleaf)) # equivalent # controlling COLOURS plot(cells, col="blue") plot(lansing, cols=c("black", "yellow", "green", "pink", "blue","red","white") plot(longleaf, fg="blue") # use selected plot characters lma <- sort(unique(longleaf$marks)) adult <- ifelse(lma >= 30, "o", "+") plot(longleaf, chars = adult) # make the plotting symbols larger (for publication at reduced scale) plot(cells, cex=2)