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Related papers: Polygon Queries for Convex Hulls of Points

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In this paper we study the statistical properties of convex hulls of $N$ random points in a plane chosen according to a given distribution. The points may be chosen independently or they may be correlated. After a non-exhaustive survey of…

Statistical Mechanics · Physics 2010-03-31 Satya N. Majumdar , Alain Comtet , Julien Randon-Furling

For $d\in\mathbb{N}$, let $S$ be a set of points in $\mathbb{R}^d$ in general position. A set $I$ of $k$ points from $S$ is a $k$-island in $S$ if the convex hull $\mathrm{conv}(I)$ of $I$ satisfies $\mathrm{conv}(I) \cap S = I$. A…

Combinatorics · Mathematics 2022-02-08 Martin Balko , Manfred Scheucher , Pavel Valtr

Let $P$ be a set of $n$ points in $d$-dimensions. The simplicial depth, $\sigma_P(q)$ of a point $q$ is the number of $d$-simplices with vertices in $P$ that contain $q$ in their convex hulls. The simplicial depth is a notion of data depth…

Computational Geometry · Computer Science 2015-12-29 Peyman Afshani , Donald R. Sheehy , Yannik Stein

An effective strategy for accelerating the calculation of convex hulls for point sets is to filter the input points by discarding interior points. In this paper, we present such a straightforward and efficient preprocessing approach by…

Computational Geometry · Computer Science 2014-05-30 Gang Mei

In this paper, we study the problem of computing a minimum-width axis-aligned cubic shell that encloses a given set of $n$ points in a three-dimensional space. A cubic shell is a closed volume between two concentric and face-parallel cubes.…

Computational Geometry · Computer Science 2019-04-16 Sang Won Bae

We consider the following problem: Preprocess a set $\mathcal{S}$ of $n$ axis-parallel boxes in $\mathbb{R}^d$ so that given a query of an axis-parallel box in $\mathbb{R}^d$, the pairs of boxes of $\mathcal{S}$ whose intersection…

Computational Geometry · Computer Science 2018-01-24 Eunjin Oh , Hee-Kap Ahn

We consider the convex hull of the perturbed point process comprised of $n$ i.i.d. points, each distributed as the sum of a uniform point on the unit sphere $\S^{d-1}$ and a uniform point in the $d$-dimensional ball centered at the origin…

Probability · Mathematics 2019-12-24 Pierre Calka , J. E. Yukich

We improve upon the running time for finding a point in a convex set given a separation oracle. In particular, given a separation oracle for a convex set $K\subset \mathbb{R}^n$ contained in a box of radius $R$, we show how to either find a…

Data Structures and Algorithms · Computer Science 2015-11-06 Yin Tat Lee , Aaron Sidford , Sam Chiu-wai Wong

Divide-and-conquer is a central paradigm for the design of algorithms, through which some fundamental computational problems, such as sorting arrays and computing convex hulls, are solved in optimal time within $\Theta(n\log{n})$ in the…

Data Structures and Algorithms · Computer Science 2015-09-28 Jeremy Barbay , Carlos Ochoa , Pablo Perez-Lantero

A fundamental problem in computational geometry is to compute an obstacle-avoiding Euclidean shortest path between two points in the plane. The case of this problem on polygonal obstacles is well studied. In this paper, we consider the…

Computational Geometry · Computer Science 2015-04-28 Danny Z. Chen , Haitao Wang

We consider space-bounded computations on a random-access machine (RAM) where the input is given on a read-only random-access medium, the output is to be produced to a write-only sequential-access medium, and the available workspace allows…

Data Structures and Algorithms · Computer Science 2015-10-27 Omar Darwish , Amr Elmasry , Jyrki Katajainen

This paper considers the problem of computing the weak visibility polygon (WVP) of any query line segment pq (or WVP(pq)) inside a given simple polygon P. We present an algorithm that preprocesses P and creates a data structure from which…

Computational Geometry · Computer Science 2013-10-01 Mojtaba Nouri Bygi , Mohammad Ghodsi

We devise a polynomial-time approximation scheme for the classical geometric problem of finding an approximate short path amid weighted regions. In this problem, a triangulated region P comprising of n vertices, a positive weight associated…

Computational Geometry · Computer Science 2016-12-08 R Inkulu , Sanjiv Kapoor

We present a number of new results about range searching for colored (or "categorical") data: 1. For a set of $n$ colored points in three dimensions, we describe randomized data structures with $O(n\mathop{\rm polylog}n)$ space that can…

Data Structures and Algorithms · Computer Science 2020-03-27 Timothy M. Chan , Qizheng He , Yakov Nekrich

This article describes a method to compute successive convex approximations of the convex hull of a set of points in R^n that are the solutions to a system of polynomial equations over the reals. The method relies on sums of squares of…

Optimization and Control · Mathematics 2010-07-27 João Gouveia , Rekha R. Thomas

We consider the following geometric optimization problem: find a convex polygon of maximum area contained in a given simple polygon $P$ with $n$ vertices. We give a randomized near-linear-time $(1-\varepsilon)$-approximation algorithm for…

Computational Geometry · Computer Science 2017-10-17 Sergio Cabello , Josef Cibulka , Jan Kynčl , Maria Saumell , Pavel Valtr

Given a set $ P $ of $n$ points and a set $ H $ of $n$ half-planes in the plane, we consider the problem of computing a smallest subset of points such that each half-plane contains at least one point of the subset. The previously best…

Computational Geometry · Computer Science 2025-01-07 Gang Liu , Haitao Wang

We consider the planar two-center problem for a convex polygon: given a convex polygon in the plane, find two congruent disks of minimum radius whose union contains the polygon. We present an $O(n\log n)$-time algorithm for the two-center…

Computational Geometry · Computer Science 2021-05-14 Jongmin Choi , Dahye Jeong , Hee-Kap Ahn

Let $\mathcal{O}$ be a set of $k$ orientations in the plane, and let $P$ be a simple polygon in the plane. Given two points $p,q$ inside $P$, we say that $p$ $\mathcal{O}$-\emph{sees} $q$ if there is an $\mathcal{O}$-\emph{staircase}…

Computational Geometry · Computer Science 2024-12-18 Alejandra Martinez-Moraian , David Orden , Leonidas Palios , Carlos Seara , Paweł Żyliński

Given a convex polyhedron $P$ of $n$ vertices inside a sphere $Q$, we give an $O(n^3)$-time algorithm that cuts $P$ out of $Q$ by using guillotine cuts and has cutting cost $O((\log n)^2)$ times the optimal.

Computational Geometry · Computer Science 2010-03-10 Syed Ishtiaque Ahmed , Masud Hasan , Md. Ariful Islam