geometry (version 0.3-2)

tsearch: Search for the enclosing Delaunay convex hull

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).

See Also

tsearchn, delaunayn