plot.tile.list {deldir} | R Documentation |
Plot Dirichlet (Voronoi) tiles
Description
A method for plot
. Plots (sequentially)
the tiles associated with each point in the set being tessellated.
Usage
## S3 method for class 'tile.list'
plot(x, verbose = FALSE, close = FALSE, pch = 1,
fillcol = getCol(x,warn=warn), col.pts=NULL,
col.num=NULL,border=NULL, showpoints = !number,
add = FALSE, asp = 1, clipp=NULL, xlab = "x",
ylab = "y", main = "", warn=TRUE,
number=FALSE,adj=NULL,...)
Arguments
x |
A list of the tiles in a tessellation, as produced
the function |
verbose |
Logical scalar; if |
close |
Logical scalar; if |
pch |
The plotting character (or vector of plotting
characters) with which to plot the points of the pattern which
was tessellated. Ignored if |
fillcol |
Optional vector (possibly of length 1, i.e. a scalar) whose
entries can be interpreted as colours by |
col.pts |
Optional vector like unto |
col.num |
Optional vector like unto |
border |
A scalar that can be interpreted as a colour by |
showpoints |
Logical scalar; if |
add |
Logical scalar; should the plot of the tiles be added to an existing plot? |
asp |
The aspect ratio of the plot; integer scalar or
|
clipp |
An object specifying a polygon to which the tessellation being plotted should be clipped. It should consist either of:
If this argument is provided then the plot of the tessellation
is “clipped” to the polygon specified by |
xlab |
Label for the |
ylab |
Label for the |
main |
A title for the plot (used only if |
warn |
Logical scalar passed to the internal function |
number |
Logical scalar; if |
adj |
The “adjustment” argument to |
... |
Optional arguments; may be passed to |
Value
NULL; side effect is a plot.
Warnings
The behaviour of this function with respect to “clipping” has changed substantially since the previous release of
deldir
, i.e. 1.1-0. The argumentclipwin
has been re-namedclipp
(“p” for “polygon”). Clipping is now effected via the new packagepolyclip
. Thespatstat
package is no longer used. The argumentuse.gpclib
has been eliminated, sincegpclib
(which used to be called upon byspatstat
has been superseded bypolyclip
which has an unrestrictive license.As of release 0.1-1 of the
deldir
package, the argumentfillcol
to this function replaces the old argumentpolycol
, but behaves somewhat differently.The argument
showrect
which was present in versions of this function prior to release 0.1-1 has been eliminated. It was redundant.As of release 0.1-1 the
col.pts
argument might behave somewhat differently from how it behaved in the past.The arguments
border
,clipp
, andwarn
are new as of release 0.1-1.Users, unless they really understand what they are doing and why they are doing it, are strongly advised not to set the value of
asp
but rather to leaveasp
equal to its default value of1
. Any other value distorts the tesselation and destroys the perpendicular appearance of lines which are indeed perpendicular. (And conversely can cause lines which are not perpendicular to appear as if they are.)
Notes
If
clipp
is notNULL
andshowpoints
isTRUE
then it is possible that some of the points “shown” will not fall inside any of the plotted tiles. (This will happen if the parts of the tiles in which they fall have been “clipped” out.) If a tile is clipped out completely then the point which determines that tile is not plotted irrespective of the value ofshowpoints
.If the
z
components of the entries ofx
cannot all be interpreted as colours (e.g. if there aren't anyz
components, which will be the case if no such values were supplied in the call todeldir()
) then the internal functiongetCol()
returnsNA
. This value offillcol
results (as is indicated by the argument list entry forfillcol
) in (all of) the tiles being left unfilled.The new behaviour in respect of the colours with which to fill the plotted tiles, and the argument
clipp
were added at the request of Chris Triggs.The argument
asp
was added at the request of Zubin Dowlaty (who presumably knows what he's doing!).
Author(s)
Rolf Turner r.turner@auckland.ac.nz
See Also
deldir()
, tile.list()
,
triang.list()
, plot.triang.list()
Examples
set.seed(42)
x <- runif(20)
y <- runif(20)
z <- deldir(x,y,rw=c(0,1,0,1))
w <- tile.list(z)
plot(w)
ccc <- heat.colors(20) # Or topo.colors(20), or terrain.colors(20)
# or cm.colors(20), or rainbow(20).
plot(w,fillcol=ccc,close=TRUE)
if(require(polyclip)) {
CP <- list(x=c(0.49,0.35,0.15,0.20,0.35,0.42,
0.43,0.62,0.46,0.63,0.82,0.79),
y=c(0.78,0.86,0.79,0.54,0.58,0.70,
0.51,0.46,0.31,0.20,0.37,0.54))
cul <- rainbow(10)[c(1,7,3:6,2,8:10)] # Rearranging colours to improve
# the contrast between contiguous tiles.
plot(w,clipp=CP,showpoints=FALSE,fillcol=cul)
}
plot(w,number=TRUE,col.num="red")
plot(w,number=TRUE,col.num="red",cex=0.5)
plot(w,showpoints=TRUE,number=TRUE,col.pts="green",col.num="red")