R: Search for the enclosing Delaunay convex hull

tsearchn {geometry} | R Documentation

## Search for the enclosing Delaunay convex hull

### Description

For `t = delaunayn(x)`, where `x` is a set of points in `d` dimensions, `tsearchn(x, t, xi)` finds the index in `t` containing the points `xi`. For points outside the convex hull, `idx` is `NA`. `tsearchn` also returns the barycentric coordinates `p` of the enclosing triangles.

### Usage

    tsearchn(x, t, xi, fast = TRUE)

### Arguments

`x` | An `n`-by-`d` matrix. The rows of `x` represent `n` points in `d`-dimensional space.
`t` | A `m`-by-`d+1` matrix. A row of `t` contains indices into `x` of the vertices of a `d`-dimensional simplex. `t` is usually the output of delaunayn.
`xi` | An `ni`-by-`d` matrix. The rows of `xi` represent `n` points in `d`-dimensional space whose positions in the mesh are being sought.
`fast` | If the data is in 2D, use the fast C-based `tsearch` function to produce the results.

### Value

A list containing:

`list("idx")` | An `ni`-long vector containing the indicies of the row of `t` in which each point in `xi` is found.
`list("p")` | An `ni`-by-`d+1` matrix containing the barycentric coordinates with respect to the enclosing simplex of each point in `xi`.

### Note

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

### Author(s)

David Sterratt

### See Also

tsearch, delaunayn

[Package geometry version 0.3-6 Index]