A Revised Implementation of the Reverse Search Vertex Enumeration Algorithm

Abstract

This paper describes an improved implementation of the reverse search vertex enumeration/convex hull algorithm for d-dimensional convex polyhedra. The implementation uses a lexicographic ratio test to resolve degeneracy, works on bounded or unbounded polyhedra and uses exact arithmetic with all integer pivoting. It can also be used to compute the volume of the convex hull of a set of points. For a polyhedron with m inequalities indvariables and known extreme point, it finds all bases in time O(md)² per basis. This implementation can handle problems of quite large size, especially for simple polyhedra (where each basis corresponds to a vertex and the complexity reduces to O (md) per vertex). Computational experience is included in the paper, including a comparison with an earlier implementation.