Bose P., De Carufel JL., Shaikhet A., Smid M. (2016) Essential Constraints of Edge-Constrained Proximity Graphs. In: Mäkinen V., Puglisi S., Salmela L. (eds) Combinatorial Algorithms. IWOCA 2016. Lecture Notes in Computer Science, vol 9843. Springer, Cham
Given a plane forest \(F = (V, E)\) of \(|V| = n\) points, we find the minimum set \(S \subseteq E\) of edges such that the edge-constrained minimum spanning tree over the set V of vertices and the set S of constraints contains F. We present an \(O(n \log n)\)-time algorithm that solves this problem. We generalize this to other proximity graphs in the constraint setting, such as the relative neighbourhood graph, Gabriel graph, \(\beta \)-skeleton and Delaunay triangulation.
We present an algorithm that identifies the minimum set \(S\subseteq E\) of edges of a given plane graph \(I=(V,E)\) such that \(I \subseteq CG_\beta (V, S)\) for \(1 \le \beta \le 2\), where \(CG_\beta (V, S)\) is the constraint \(\beta \)-skeleton over the set V of vertices and the set S of constraints. The running time of our algorithm is O(n), provided that the constrained Delaunay triangulation of I is given.