interp (version 1.0-29)

on.convex.hull: Determines if points are on or in the convex hull of a triangulation object

Description

Given a triangulation object tri.obj of \(n\) points in the plane, this subroutine returns a logical vector indicating if the points \((x_i,y_i)\) lay on or in the convex hull of tri.obj.

Usage

on.convex.hull(tri.obj, x, y, eps=1E-16)
in.convex.hull(tri.obj, x, y, eps=1E-16)

Arguments

tri.obj

object of class triSht

x

vector of \(x\)-coordinates of points to locate

y

vector of \(y\)-coordinates of points to locate

eps

accuracy for checking the condition

Value

Logical vector.

See Also

triSht, print.triSht, plot.triSht, summary.triSht, triangles, convex.hull.

Examples

# NOT RUN {
# use a part of the quakes data set:
data(quakes)
quakes.part<-quakes[(quakes[,1]<=-10.78 & quakes[,1]>=-19.4 &
                     quakes[,2]<=182.29 & quakes[,2]>=165.77),]
q.tri<-tri.mesh(quakes.part$lon, quakes.part$lat, duplicate="remove")
on.convex.hull(q.tri,quakes.part$lon[1:20],quakes.part$lat[1:20])
in.convex.hull(q.tri,quakes.part$lon[1:20],quakes.part$lat[1:20])
# }