tsearch: Search for the enclosing Delaunay convex hull

In geometry: Mesh Generation and Surface Tesselation

Description

For t = delaunay(cbind(x, y)), where (x, y) is a 2D set of points, tsearch(x, y, t, xi, yi) finds the index in t containing the points (xi, yi). For points outside the convex hull the index is NA.

Usage

tsearch(x, y, t, xi, yi, bary = FALSE)

Arguments

x	X-coordinates of triangluation points
y	Y-coordinates of triangluation points
t	Triangulation, e.g. produced by t = delaunayn(cbind(x, y))
xi	X-coordinates of points to test
yi	Y-coordinates of points to test
bary	If TRUE return barycentric coordinates as well as index of triangle.

Value

If bary is FALSE, the index in t containing the points (xi, yi). For points outside the convex hull the index is NA. If bary is TRUE, a list containing:

list("idx")	the index in t containing the points (xi, yi)
list("p")	a 3-column matrix containing the barycentric coordinates with respect to the enclosing triangle of each point code(xi, yi).

Note

Based on the Octave function Copyright (C) 2007-2012 David Bateman.

Author(s)

David Sterratt

See Also

tsearchn, delaunayn

geometry documentation built on May 2, 2019, 6:09 p.m.