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Related papers: Approximating Convex Hulls via Range Queries

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We show {\it semidefinite programming} (SDP) feasibility problem is equivalent to solving a {\it convex hull relaxation} (CHR) for a finite system of quadratic equations. On the one hand, this offers a simple description of SDP. On the…

Optimization and Control · Mathematics 2020-08-18 Bahman Kalantari

We study entropy-bounded computational geometry, that is, geometric algorithms whose running times depend on a given measure of the input entropy. Specifically, we introduce a measure that we call range-partition entropy, which unifies and…

Computational Geometry · Computer Science 2025-08-29 David Eppstein , Michael T. Goodrich , Abraham M. Illickan , Claire A. To

We consider the problem of tabular infinite horizon concave utility reinforcement learning (CURL) with convex constraints. For this, we propose a model-based learning algorithm that also achieves zero constraint violations. Assuming that…

Machine Learning · Computer Science 2023-11-20 Mridul Agarwal , Qinbo Bai , Vaneet Aggarwal

The aperture angle alpha(x, Q) of a point x not in Q in the plane with respect to a convex polygon Q is the angle of the smallest cone with apex x that contains Q. The aperture angle approximation error of a compact convex set C in the…

Computational Geometry · Computer Science 2010-08-26 Hee-Kap Ahn , Sang Won Bae , Otfried Cheong , Joachim Gudmundsson

In general dimension, there is no known total polynomial algorithm for either convex hull or vertex enumeration, i.e. an algorithm whose complexity depends polynomially on the input and output sizes. It is thus important to identify…

Computational Geometry · Computer Science 2021-04-26 Ioannis Z. Emiris , Vissarion Fisikopoulos , Bernd Gärtner

We study several polygonal curve problems under the Fr\'{e}chet distance via algebraic geometric methods. Let $\mathbb{X}_m^d$ and $\mathbb{X}_k^d$ be the spaces of all polygonal curves of $m$ and $k$ vertices in $\mathbb{R}^d$,…

Computational Geometry · Computer Science 2023-10-24 Siu-Wing Cheng , Haoqiang Huang

Polytopes are the basic finite data structures for convex sets: they appear as feasible regions in linear optimization, as geometric summaries in algorithms, and as random objects in stochastic geometry. A natural geometric question is…

Metric Geometry · Mathematics 2026-03-10 Steven Hoehner

We study a general smallest intersecting ball problem and its soft-margin variant in high-dimensional Euclidean spaces for input objects that are compact and convex. These two problems link and unify a series of fundamental problems in…

Computational Geometry · Computer Science 2025-05-27 Jiaqi Zheng , Tiow-Seng Tan

Recently, several studies consider the stochastic optimization problem but in a heavy-tailed noise regime, i.e., the difference between the stochastic gradient and the true gradient is assumed to have a finite $p$-th moment (say being upper…

Optimization and Control · Mathematics 2023-05-23 Zijian Liu , Zhengyuan Zhou

We give the first nontrivial upper and lower bounds on the maximum volume of an empty axis-parallel box inside an axis-parallel unit hypercube in $\RR^d$ containing $n$ points. For a fixed $d$, we show that the maximum volume is of the…

Computational Geometry · Computer Science 2009-11-23 Adrian Dumitrescu , Minghui Jiang

We prove that the combinatorial optimization problem of determining the hull number of a partial cube is NP-complete. This makes partial cubes the minimal graph class for which NP-completeness of this problem is known and improves some…

Combinatorics · Mathematics 2015-10-09 Marie Albenque , Kolja Knauer

This article resides in the realm of the noncommutative (free) analog of real algebraic geometry - the study of polynomial inequalities and equations over the real numbers - with a focus on matrix convex sets $C$ and their projections $\hat…

Functional Analysis · Mathematics 2018-04-27 J. William Helton , Igor Klep , Scott McCullough

We consider a step search method for continuous optimization under a stochastic setting where the function values and gradients are available only through inexact probabilistic zeroth- and first-order oracles. Unlike the stochastic gradient…

Optimization and Control · Mathematics 2023-11-03 Billy Jin , Katya Scheinberg , Miaolan Xie

Approximating convex bodies succinctly by convex polytopes is a fundamental problem in discrete geometry. A convex body $K$ of diameter $\mathrm{diam}(K)$ is given in Euclidean $d$-dimensional space, where $d$ is a constant. Given an error…

Computational Geometry · Computer Science 2018-01-11 Sunil Arya , Guilherme D. da Fonseca , David M. Mount

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

Given a set $\Sigma$ of spheres in $\mathbb{E}^d$, with $d\ge{}3$ and $d$ odd, having a fixed number of $m$ distinct radii $\rho_1,\rho_2,...,\rho_m$, we show that the worst-case combinatorial complexity of the convex hull $CH_d(\Sigma)$ of…

Computational Geometry · Computer Science 2011-06-14 Menelaos I. Karavelas , Eleni Tzanaki

We study nonconvex optimization landscapes for learning overcomplete representations, including learning (i) sparsely used overcomplete dictionaries and (ii) convolutional dictionaries, where these unsupervised learning problems find many…

Machine Learning · Computer Science 2019-12-11 Qing Qu , Yuexiang Zhai , Xiao Li , Yuqian Zhang , Zhihui Zhu

We study the approximate range searching for three variants of the clustering problem with a set $P$ of $n$ points in $d$-dimensional Euclidean space and axis-parallel rectangular range queries: the $k$-median, $k$-means, and $k$-center…

Computational Geometry · Computer Science 2018-03-13 Eunjin Oh , Hee-Kap Ahn

In the optimization of convex domains under a PDE constraint numerical difficulties arise in the approximation of convex domains in $\mathbb{R}^3$. Previous research used a restriction to rotationally symmetric domains to reduce shape…

Numerical Analysis · Mathematics 2023-11-23 Sören Bartels , Hedwig Keller , Gerd Wachsmuth

We study the convex hull of a set $S\subset \mathbb{R}^n$ defined by three quadratic inequalities. A simple way of generating inequalities valid on $S$ is to take nonnegative linear combinations of the defining inequalities of $S$. We call…

Algebraic Geometry · Mathematics 2024-05-29 Grigoriy Blekherman , Alex Dunbar
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