English

Connectivity with uncertainty regions given as line segments

Computational Geometry 2023-12-13 v2 Data Structures and Algorithms Optimization and Control

Abstract

For a set QQ of points in the plane and a real number δ0\delta \ge 0, let Gδ(Q)\mathbb{G}_\delta(Q) be the graph defined on QQ by connecting each pair of points at distance at most δ\delta. We consider the connectivity of Gδ(Q)\mathbb{G}_\delta(Q) in the best scenario when the location of a few of the points is uncertain, but we know for each uncertain point a line segment that contains it. More precisely, we consider the following optimization problem: given a set PP of nkn-k points in the plane and a set SS of kk line segments in the plane, find the minimum δ0\delta\ge 0 with the property that we can select one point pssp_s\in s for each segment sSs\in S and the corresponding graph Gδ(P{pssS})\mathbb{G}_\delta ( P\cup \{ p_s\mid s\in S\}) is connected. It is known that the problem is NP-hard. We provide an algorithm to exactly compute an optimal solution in O(f(k)nlogn)O(f(k) n \log n) time, for a computable function f()f(\cdot). This implies that the problem is FPT when parameterized by kk. The best previous algorithm uses O((k!)kkk+1n2k)O((k!)^k k^{k+1}\cdot n^{2k}) time and computes the solution up to fixed precision.

Keywords

Cite

@article{arxiv.2303.10028,
  title  = {Connectivity with uncertainty regions given as line segments},
  author = {Sergio Cabello and David Gajser},
  journal= {arXiv preprint arXiv:2303.10028},
  year   = {2023}
}

Comments

30 pages, 9 figures

R2 v1 2026-06-28T09:21:41.898Z