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Imprecise measurements of a point set P = (p1, ..., pn) can be modelled by a family of regions F = (R1, ..., Rn), where each imprecise region Ri contains a unique point pi. A retrieval models an accurate measurement by replacing an…

Computational Geometry · Computer Science 2025-12-09 Sarita de Berg , Ivor van der Hoog , Eva Rotenberg , Daniel Rutschmann , Sampson Wong

We consider the Minimum Convex Partition problem: Given a set P of n points in the plane, draw a plane graph G on P, with positive minimum degree, such that G partitions the convex hull of P into a minimum number of convex faces. We show…

Computational Geometry · Computer Science 2021-12-22 Nicolas Grelier

We analyze the correctness of an O(n log n) time divide-and-conquer algorithm for the convex hull problem when each input point is a location determined by a normal distribution. We show that the algorithm finds the convex hull of such…

Computational Geometry · Computer Science 2016-08-08 F. Betul Atalay , Sorelle A. Friedler , Dianna Xu

We consider the problem of computing the time-convex hull of a point set under the general $L_p$ metric in the presence of a straight-line highway in the plane. The traveling speed along the highway is assumed to be faster than that off the…

Computational Geometry · Computer Science 2013-05-01 Bang-Sin Dai , Mong-Jen Kao , D. T. Lee

A new algorithm for the determination of the relative convex hull in the plane of a simple polygon A with respect to another simple polygon B which contains A, is proposed. The relative convex hull is also known as geodesic convex hull, and…

Computational Geometry · Computer Science 2016-05-02 P. Wiederhold , H. Reyes

Given a point set $P$ in the plane, we seek a subset $Q\subseteq P$, whose convex hull gives a smaller and thus simpler representation of the convex hull of $P$. Specifically, let $cost(Q,P)$ denote the Hausdorff distance between the convex…

Computational Geometry · Computer Science 2021-10-05 Georgiy Klimenko , Benjamin Raichel

We explore the separability of point sets in the plane by a restricted-orientation convex hull, which is an orientation-dependent, possibly disconnected, and non-convex enclosing shape that generalizes the convex hull. Let $R$ and $B$ be…

Computational Geometry · Computer Science 2022-09-12 Carlos Alegría , David Orden , Carlos Seara , Jorge Urrutia

We study the Tukey layers and convex layers of a planar point set, which consists of $n$ points independently and uniformly sampled from a convex polygon with $k$ vertices. We show that the expected number of vertices on the first $t$ Tukey…

Computational Geometry · Computer Science 2021-09-16 Zhengyang Guo , Yi Li , Shaoyu Pei

The convex hull peeling of a point set consists in taking the convex hull, then removing the extreme points and iterating that procedure until no point remains. The boundary of each hull is called a layer. Following on from [15], we study…

Probability · Mathematics 2024-10-10 Pierre Calka , Gauthier Quilan

Finding the coordinate-wise maxima and the convex hull of a planar point set are probably the most classic problems in computational geometry. We consider these problems in the self-improving setting. Here, we have $n$ distributions…

Computational Geometry · Computer Science 2014-04-29 Kenneth L. Clarkson , Wolfgang Mulzer , C. Seshadhri

Many classical algorithms are known for computing the convex hull of a set of $n$ point in $\mathbb{R}^2$ using $O(n)$ space. For large point sets, whose size exceeds the size of the working space, these algorithms cannot be directly used.…

Computational Geometry · Computer Science 2018-10-02 Martin Farach-Colton , Meng Li , Meng-Tsung Tsai

For a finite point set in $\mathbb{R}^d$, we consider a peeling process where the vertices of the convex hull are removed at each step. The layer number $L(X)$ of a given point set $X$ is defined as the number of steps of the peeling…

Combinatorics · Mathematics 2020-06-05 Ilkyoo Choi , Weonyoung Joo , Minki Kim

The convex hull describes the extent or shape of a set of data and is used ubiquitously in computational geometry. Common algorithms to construct the convex hull on a finite set of n points (x,y) range from O(nlogn) time to O(n) time.…

Computational Geometry · Computer Science 2015-05-06 José O. Cadenas , Graham Megson

Chv\'{a}tal and Klincsek (1980) gave an $O(n^3)$-time algorithm for the problem of finding a maximum-cardinality convex subset of an arbitrary given set $P$ of $n$ points in the plane. This paper examines a generalization of the problem,…

Computational Geometry · Computer Science 2021-08-31 Stephane Durocher , J. Mark Keil , Saeed Mehrabi , Debajyoti Mondal

We consider the problem of computing Shapley values for points in the plane, where each point is interpreted as a player, and the value of a coalition is defined by the area of usual geometric objects, such as the convex hull or the minimum…

Computational Geometry · Computer Science 2018-11-30 Sergio Cabello , Timothy M. Chan

Let $P$ be a set of $n$ labeled points in the plane. The radial system of $P$ describes, for each $p\in P$, the order in which a ray that rotates around $p$ encounters the points in $P \setminus \{p\}$. This notion is related to the order…

Computational Geometry · Computer Science 2017-09-18 Oswin Aichholzer , Vincent Kusters , Wolfgang Mulzer , Alexander Pilz , Manuel Wettstein

Convex hulls are fundamental geometric tools used in a number of algorithms. This paper presents a fast, simple to implement and robust Smart Convex Hull (S-CH) algorithm for computing the convex hull of a set of points in E3. This…

Data Structures and Algorithms · Computer Science 2017-08-10 Vaclav Skala , Zuzana Majdisova , Michal Smolik

Let $P$ be a set of $n$ points in general position on the plane. A set of closed convex polygons with vertices in $P$, and with pairwise disjoint interiors is called a convex decomposition of $P$ if their union is the convex hull of $P$,…

Combinatorics · Mathematics 2019-09-16 Toshinori Sakai , Jorge Urrutia

Prune-and-search is an important paradigm for solving many important geometric problems. We show that the general prune-and-search technique can be implemented where the objects are given in read-only memory. As examples we consider…

Computational Geometry · Computer Science 2012-12-24 Minati De , Subhas C. Nandy , Sasanka Roy

Let $P$ be a set of $n$ points in the plane. We compute the value of $\theta\in [0,2\pi)$ for which the rectilinear convex hull of $P$, denoted by $\mathcal{RH}_\theta(P)$, has minimum (or maximum) area in optimal $O(n\log n)$ time and…

Computational Geometry · Computer Science 2025-01-20 Carlos Alegría-Galicia , David Orden , Carlos Seara , Jorge Urrutia