plot.ashape {alphahull} | R Documentation |
This function returns a plot of the α-shape. If desired, it also adds the Delaunay triangulation and Voronoi diagram of the sample.
## S3 method for class 'ashape' plot(x, add = FALSE, wlines = c("none", "both", "del", "vor"), wpoints = TRUE, number = FALSE, col = NULL, xlim = NULL, ylim = NULL, lwd = NULL, ...)
x |
Object of class |
add |
Logical, if TRUE add to a current plot. |
wlines |
"Which lines?". I.e. should the Delaunay triangulation be plotted (wlines='del'), should the Voronoi diagram be plotted (wlines='vor'), should both be plotted (wlines='both'), or none (wlines='none', the default)? |
wpoints |
Logical, indicates if sample points should be plotted. |
number |
Logical, defaulting to FALSE; if TRUE then the points plotted will be labelled with their index numbers. |
col |
The colour numbers for plotting the α-shape, data points, Delaunay triangulation, Voronoi diagram, and the point numbers, in that order; defaults to c(1,1,1,1,1). If fewer than five numbers are given, they are recycled. (If more than five numbers are given, the redundant ones are ignored.) |
xlim |
The limits on the x-axis. |
ylim |
The limits on the y-axis. |
lwd |
The line widths for plotting the tesselations and the α-shape; defaults to c(1,2). |
... |
Arguments to be passed to methods, such as graphical parameters (see |
## Not run: # Uniform sample of size n=300 in the annulus B(c, 0.5)\B(c, 0.25) # with c=(0.5, 0.5). n <- 300 theta<-runif(n,0,2*pi) r<-sqrt(runif(n,0.25^2,0.5^2)) x<-cbind(0.5+r*cos(theta),0.5+r*sin(theta)) # Value of alpha alpha <- 0.1 # alpha-shape ashape.obj <- ashape(x, alpha = alpha) # Plot alpha-shape in blue, sample points in black, # and Delaunay triangulation in red plot(ashape.obj, wlines= "del", col = c(4, 1, 2)) # Random sample from a uniform distribution on a Koch snowflake # with initial side length 1 and 3 iterations x <- rkoch(2000, side = 1, niter = 3) # Value of alpha alpha <- 0.05 # alpha-shape ashape.obj <- ashape(x, alpha = alpha) # Plot alpha-shape in blue plot(ashape.obj, col = c(4, 1)) ## End(Not run)