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The Convex Hull algorithm is one of the most important algorithms in computational geometry, with many applications such as in computer graphics, robotics, and data mining. Despite the advances in the new algorithms in this area, it is…

Distributed, Parallel, and Cluster Computing · Computer Science 2023-03-21 Roberto Carrasco , Héctor Ferrada , Cristóbal A. Navarro , Nancy Hitschfeld

Let $P$ be a set of $n$ points in $\mathbb{R}^3$ in general position, and let $RCH(P)$ be the rectilinear convex hull of $P$. In this paper we obtain an optimal $O(n\log n)$-time and $O(n)$-space algorithm to compute $RCH(P)$. We also…

Computational Geometry · Computer Science 2022-09-14 Pablo Pérez-Lantero , Carlos Seara , Jorge Urrutia

We show that the polyhedron defined as the convex hull of the lattice points above the hyperbola $\left\{xy = n\right\}$ has between $\Omega(n^{1/3})$ and $O(n^{1/3} \log n)$ vertices. The same bounds apply to any hyperbola with rational…

Combinatorics · Mathematics 2025-02-03 David Alcántara , Mónica Blanco , Francisco Criado , Francisco Santos

We present a new fully dynamic algorithm for maintaining convex hulls under insertions and deletions while supporting geometric queries. Our approach combines the logarithmic method with a deletion-only convex hull data structure, achieving…

Computational Geometry · Computer Science 2026-04-02 Ivor van der Hoog , Henrik Reinstädtler , Eva Rotenberg

Writing an uncomplicated, robust, and scalable three-dimensional convex hull algorithm is challenging and problematic. This includes, coplanar and collinear issues, numerical accuracy, performance, and complexity trade-offs. While there are…

Computational Geometry · Computer Science 2023-04-11 Ben Kenwright

Computationally efficient and automated generation of convex hulls is desirable for high throughput materials discovery of thermodynamically stable multi-species crystal structures. A convex hull genetic algorithm is proposed that uses…

Materials Science · Physics 2024-04-23 Scott Donaldson , Robert A. Lawrence , Matt I. J. Probert

This paper provides full \Matlab-code and informal correctness proofs for the lexicographic reverse search algorithm for convex hull calculations. The implementation was tested on a 1993 486-PC for various small and some larger, partially…

Mathematical Software · Computer Science 2016-04-22 Alexander Kovačec , Bernardete Ribeiro

Convex hulls are fundamental objects in computational geometry. In moderate dimensions or for large numbers of vertices, computing the convex hull can be impractical due to the computational complexity of convex hull algorithms. In this…

Computational Geometry · Computer Science 2017-06-16 Robert Graham , Adam M. Oberman

In the problem of high-dimensional convexity testing, there is an unknown set $S \subseteq \mathbb{R}^n$ which is promised to be either convex or $\varepsilon$-far from every convex body with respect to the standard multivariate normal…

Computational Complexity · Computer Science 2017-06-29 Xi Chen , Adam Freilich , Rocco A. Servedio , Timothy Sun

We propose a cut-based algorithm for finding all vertices and all facets of the convex hull of all integer points of a polyhedron defined by a system of linear inequalities. Our algorithm DDM Cuts is based on the Gomory cuts and the dynamic…

Combinatorics · Mathematics 2020-10-27 S. O. Semenov , N. Yu. Zolotykh

We study the following range searching problem: Preprocess a set $P$ of $n$ points in the plane with respect to a set $\mathcal{O}$ of $k$ orientations % , for a constant, in the plane so that given an $\mathcal{O}$-oriented convex polygon…

Computational Geometry · Computer Science 2019-10-22 Eunjin Oh , Hee-Kap Ahn

In this article, a new solution for the convex hull problem has been presented. The convex hull is a widely known problem in computational geometry. As nature is a rich source of ideas in the field of algorithms, the solution has been…

Multiagent Systems · Computer Science 2022-12-26 Sina Saadati , Mohammadreza Razzazi

Let $P$ be a set of $n$ points in the plane. We consider a variation of the classical Erd\H{o}s-Szekeres problem, presenting efficient algorithms with $O(n^3)$ running time and $O(n^2)$ space complexity that compute: (1) A subset $S$ of $P$…

Computational Geometry · Computer Science 2024-12-18 Hernán González-Aguilar , David Orden , Pablo Pérez-Lantero , David Rappaport , Carlos Seara , Javier Tejel , Jorge Urrutia

The geometric congruence problem is a fundamental building block in many computer vision and image recognition tasks. This problem considers the decision task of whether two point sets are congruent under translation and rotation. A related…

Data Structures and Algorithms · Computer Science 2026-02-16 Yen-Cheng Chang , Tsun Ming Cheung , Meng-Tsung Tsai , Ting-An Wu

Computation of the vertices of the convex hull of a set $S$ of $n$ points in $\mathbb{R} ^m$ is a fundamental problem in computational geometry, optimization, machine learning and more. We present "All Vertex Triangle Algorithm" (AVTA), a…

Computational Geometry · Computer Science 2018-09-26 Pranjal Awasthi , Bahman Kalantari , Yikai Zhang

The main purpose of this paper is to report on the state of the art of computing integer hulls and their facets as well as counting lattice points in convex polytopes. Using the polymake system we explore various algorithms and…

We present new iterative algorithms for solving a square linear system $Ax=b$ in dimension $n$ by employing the {\it Triangle Algorithm} \cite{kal12}, a fully polynomial-time approximation scheme for testing if the convex hull of a finite…

Numerical Analysis · Computer Science 2012-10-31 Bahman Kalantari

Given $S= \{v_1, \dots, v_n\} \subset \mathbb{R} ^m$ and $p \in \mathbb{R} ^m$, testing if $p \in conv(S)$, the convex hull of $S$, is a fundamental problem in computational geometry and linear programming. First, we prove a Euclidean {\it…

Computational Geometry · Computer Science 2013-10-15 Bahman Kalantari

The computation of determinants or their signs is the core procedure in many important geometric algorithms, such as convex hull, volume and point location. As the dimension of the computation space grows, a higher percentage of the total…

Computational Geometry · Computer Science 2016-02-01 Vissarion Fisikopoulos , Luis Peñaranda

Motivated by the desire to cope with data imprecision, we study methods for taking advantage of preliminary information about point sets in order to speed up the computation of certain structures associated with them. In particular, we…

Computational Geometry · Computer Science 2012-12-27 Esther Ezra , Wolfgang Mulzer