halfspacen {geometry}R Documentation

Compute halfspace intersection about a point

Description

Compute halfspace intersection about a point

Usage

halfspacen(p, fp, options = "Tv")

Arguments

p

An n-by-dim+1 matrix. Each row of p represents a halfspace by a dim-dimensional normal to a hyperplane and the offset of the hyperplane.

fp

A “feasible” point that is within the space contained within all the halfspaces.

options

String containing extra options, separated by spaces, for the underlying Qhull command; see details below and Qhull documentation at http://www.qhull.org/html/qhalf.htm.

Value

A dim-column matrix containing the intersection points of the hyperplanes ../doc/qhull/html/qhalf.html. These points

Author(s)

David Sterratt david.c.sterratt@ed.ac.uk

References

Barber, C.B., Dobkin, D.P., and Huhdanpaa, H.T., “The Quickhull algorithm for convex hulls,” ACM Trans. on Mathematical Software, Dec 1996.

http://www.qhull.org

See Also

convhulln

Examples

p <- rbox(0, C=0.5)  # Generate points on a unit cube centered around the origin
ch <- convhulln(p, "n") # Generate convex hull, including normals to facets, with "n" option
# Intersections of half planes
# These points should be the same as the orginal points
pn <- halfspacen(ch$normals, c(0, 0, 0))
[Package geometry version 0.4.0 Index]