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In two dimensional digital geometry, two lattice points are 4-connected (resp. 8-connected) if their Euclidean distance is at most one (resp. $\sqrt{2}$). A set $S \subset Z^2$ is 4-connected (resp. 8-connected) if for all pair of points…

Computational Geometry · Computer Science 2021-03-09 Crombez Loïc

Convex hulls are a fundamental geometric tool used in a number of algorithms. As a side-effect of exhaustive tests for an algorithm for which a convex hull computation was the first step, interesting experimental results were found and are…

Computational Geometry · Computer Science 2013-04-10 Jean Souviron

The potato-peeling problem (also known as convex skull) is a fundamental computational geometry problem and the fastest algorithm to date runs in $O(n^8)$ time for a polygon with $n$ vertices that may have holes. In this paper, we consider…

Computational Geometry · Computer Science 2019-06-25 Loïc Crombez , Guilherme D. da Fonseca , Yan Gérard

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

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

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

We investigate several computational problems related to the stochastic convex hull (SCH). Given a stochastic dataset consisting of $n$ points in $\mathbb{R}^d$ each of which has an existence probability, a SCH refers to the convex hull of…

Computational Geometry · Computer Science 2017-05-02 Jie Xue , Yuan Li , Ravi Janardan

In this paper we present several results on the expected complexity of a convex hull of $n$ points chosen uniformly and independently from a convex shape. (i) We show that the expected number of vertices of the convex hull of $n$ points,…

Computational Geometry · Computer Science 2011-11-24 Sariel Har-Peled

This study presents a novel algorithm for identifying the set of extreme points that constitute the exact convex hull of a point set in high-dimensional Euclidean space. The proposed method iteratively solves a sequence of dynamically…

Computational Geometry · Computer Science 2025-11-11 Qianwei Zhuang

Computing the convex hull of a planar $n$-point set $P$ is one of the most fundamental problems in computational geometry. It has an $\Omega(n \log n)$ lower bound in the algebraic computation tree model, and many convex hull algorithms…

The convex hull of a data set $P$ is the smallest convex set that contains $P$. In this work, we present a new data structure for convex hull, that allows for efficient dynamic updates. In a dynamic convex hull implementation, the following…

Computational Geometry · Computer Science 2023-11-01 Emil Toftegaard Gæde , Inge Li Gørtz , Ivor van der Hoog , Christoffer Krogh , Eva Rotenberg

A novel 2-D method for computing the convex hull of a sufficiently dense set of n integer points is introduced. The approach employs a ranking function that avoids sorting the points directly thus reducing the overall time complexity. The…

Computational Geometry · Computer Science 2013-01-22 G. M. Megson , J. Cadenas

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

$\def\DD{{{\bf \delta}}}\def\CH{{\mathop{\mathrm{ConvexHull}}}}\newcommand{\LL}{{\cal {L}}} \newcommand{\ZZ}{\mathbb{Z}} $ Given a convex body $C$ in the plane, its discrete hull is $C^0 = \CH( C \cap \LL )$, where $\LL = \ZZ \times \ZZ$ is…

Computational Geometry · Computer Science 2026-01-05 Sariel Har-Peled

Given a finite set of points $P \subseteq \mathbb{R}^d$, we would like to find a small subset $S \subseteq P$ such that the convex hull of $S$ approximately contains $P$. More formally, every point in $P$ is within distance $\epsilon$ from…

Computational Geometry · Computer Science 2017-12-15 Avrim Blum , Vladimir Braverman , Ananya Kumar , Harry Lang , Lin F. Yang

We develop a sketching algorithm to find the point on the convex hull of a dataset, closest to a query point outside it. Studying the convex hull of datasets can provide useful information about their geometric structure and their…

Differential Geometry · Mathematics 2022-03-30 Roozbeh Yousefzadeh

In this paper, an effective method with time complexity of $\mathcal{O}(K^{3/2}N^2\log \frac{K}{\epsilon_0})$ is introduced to find an approximation of the convex hull for $N$ points in dimension $n$, where $K$ is close to the number of…

Computational Geometry · Computer Science 2016-03-15 Hossein Sartipizadeh , Tyrone L. Vincent

We consider the problem of reporting convex hull points in an orthogonal range query in two dimensions. Formally, let $P$ be a set of $n$ points in $\mathbb{R}^{2}$. A point lies on the convex hull of a point set $S$ if it lies on the…

Computational Geometry · Computer Science 2013-07-24 Jatin Agarwal , Nadeem Moidu , Kishore Kothapalli , Kannan Srinathan

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

We consider an algorithmic problem inspired by the Battleship game. In the variant of the problem that we investigate, there is a unique ship of shape $S \subset Z^2$ which has been translated in the lattice $Z^2$. We assume that a player…

Computational Geometry · Computer Science 2020-04-17 Loïc Crombez , Guilherme D. da Fonseca , Yan Gerard
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