inahull {alphahull} | R Documentation |
This function determines for one or more points p whether they belong to the α-convex hull of a sample.
inahull(ahull.obj, p)
ahull.obj |
Object of class |
p |
Numeric vector with two components describing a point in the plane or two-column matrix of points. |
The complement of the α-convex hull of a sample is calculated by complement
. The function inahull
checks whether each point in p belongs to any of the open balls or halfplanes that define the complement.
in.ahull |
A logical vector specifying whether each point in p belongs to the α-convex hull. |
## Not run: # Random sample in the unit square x <- matrix(runif(100), nc = 2) # Value of alpha alpha <- 0.2 # alpha-convex hull ahull.obj <- ahull(x, alpha = alpha) # Check if the point (0.5, 0.5) belongs to the alpha-convex hull inahull(ahull.obj, p = c(0.5, 0.5)) # Check if the points (0.5, 0.5) and (2, 2) belong to the alpha-convex hull inahull(ahull.obj, p = rbind(c(0.5, 0.5), c(2, 2))) ## End(Not run)