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Given a set of N points, we have discovered an algorithm that can separate these points from one another by n-dimensional planes. Each point is chosen at random and put into a set S and planes which separate them are determined and put into…

Computational Geometry · Computer Science 2015-10-26 K. Eswaran

A simplicial vertex of a graph is a vertex whose neighborhood is a clique. It is known that listing all simplicial vertices can be done in $O(nm)$ time or $O(n^{\omega})$ time, where $O(n^{\omega})$ is the time needed to perform a fast…

Data Structures and Algorithms · Computer Science 2022-05-04 Charis Papadopoulos , Athanasios Zisis

In this paper, we analyze the time complexity of finding regular polygons in a set of n points. We combine two different approaches to find regular polygons, depending on their number of edges. Our result depends on the parameter alpha,…

Computational Geometry · Computer Science 2009-08-19 Greg Aloupis , Jean Cardinal , Sebastien Collette , John Iacono , Stefan Langerman

We show that in the quantum query model the complexity of detecting a triangle in an undirected graph on $n$ nodes can be done using $O(n^{1+{3\over 7}}\log^{2}n)$ quantum queries. The same complexity bound applies for outputting the…

Quantum Physics · Physics 2007-05-23 Mario Szegedy

Object counting is an important task in computer vision due to its growing demand in applications such as surveillance, traffic monitoring, and counting everyday objects. State-of-the-art methods use regression-based optimization where they…

Computer Vision and Pattern Recognition · Computer Science 2018-07-27 Issam H. Laradji , Negar Rostamzadeh , Pedro O. Pinheiro , David Vazquez , Mark Schmidt

In this article we consider the problem of finding the visibility set from a given point when the obstacles are represented as the level set of a given function. Although the visibility set can be computed efficiently by ray tracing, there…

Analysis of PDEs · Mathematics 2019-08-05 Adam Oberman , Tiago Salvador

Several biological problems require the identification of regions in a sequence where some feature occurs within a target density range: examples including the location of GC-rich regions, identification of CpG islands, and sequence…

Data Structures and Algorithms · Computer Science 2013-08-15 Benjamin A. Burton , Mathias Hiron

We study the aggregate/group nearest neighbor searching for the MAX operator in the plane. For a set $P$ of $n$ points and a query set $Q$ of $m$ points, the query asks for a point of $P$ whose maximum distance to the points in $Q$ is…

Computational Geometry · Computer Science 2013-09-10 Haitao Wang

The reachability problem asks to decide if there exists a path from one vertex to another in a digraph. In a grid digraph, the vertices are the points of a two-dimensional square grid, and an edge can occur between a vertex and its…

Computational Complexity · Computer Science 2025-01-03 Rahul Jain , Raghunath Tewari

Visibility plays an important role for decision making in cluttered, uncertain environments. This paper considers the problem of identifying optimal hiding spots for an agent against line-of-sight detection by an adversary whose location is…

Optimization and Control · Mathematics 2026-02-02 Neilabh Banzal , Jorge Cortés , Sonia Martínez

We present subquadratic algorithms in the algebraic decision-tree model for several \textsc{3Sum}-hard geometric problems, all of which can be reduced to the following question: Given two sets $A$, $B$, each consisting of $n$ pairwise…

Computational Geometry · Computer Science 2021-09-17 Boris Aronov , Mark de Berg , Jean Cardinal , Esther Ezra , John Iacono , Micha Sharir

Acceleration of algorithms is becoming a crucial problem, if larger data sets are to be processed. Evaluation of algorithms is mostly done by using computational geometry approach and evaluation of computational complexity. However in…

Computational Geometry · Computer Science 2022-08-29 Vaclav Skala

Class-agnostic object counting aims to count all objects in an image with respect to example boxes or class names, \emph{a.k.a} few-shot and zero-shot counting. In this paper, we propose a generalized framework for both few-shot and…

Computer Vision and Pattern Recognition · Computer Science 2024-03-28 Zhizhong Huang , Mingliang Dai , Yi Zhang , Junping Zhang , Hongming Shan

More than 25 years ago Chazelle~\emph{et al.} (FOCS 1991) studied the following question: Is it possible to cut any set of $n$ lines in ${\Bbb R}^3$ into a subquadratic number of fragments such that the resulting fragments admit a depth…

Computational Geometry · Computer Science 2017-04-07 Mark de Berg

In this article, we devise a concise algorithm for computing BOCP. Our method is simple, easy-to-implement but without loss of efficiency. Given two circular-arc polygons with $m$ and $n$ edges respectively, our method runs in…

Data Structures and Algorithms · Computer Science 2018-07-04 Jack Wang

Determining visibility in planar polygons and arrangements is an important subroutine for many algorithms in computational geometry. In this paper, we report on new implementations, and corresponding experimental evaluations, for two…

Computational Geometry · Computer Science 2014-03-18 Francisc Bungiu , Michael Hemmer , John Hershberger , Kan Huang , Alexander Kröller

We show that a large fraction of the data-structure lower bounds known today in fact follow by reduction from the communication complexity of lopsided (asymmetric) set disjointness. This includes lower bounds for: * high-dimensional…

Data Structures and Algorithms · Computer Science 2010-10-20 Mihai Patrascu

Given a set of $m$ points and a set of $n$ lines in the plane, we consider the problem of computing the faces of the arrangement of the lines that contain at least one point. In this paper, we present an $O(m^{2/3}n^{2/3}+(n+m)\log n)$ time…

Computational Geometry · Computer Science 2026-03-06 Haitao Wang

We explore the problem of $M$-guarding polygons with holes using $k$-visibility guards, where a set of guards is said to $M$-guard a polygon if every point in the polygon is visible to at least $M$ guards, with the constraint that there may…

Computational Geometry · Computer Science 2025-10-30 Yeganeh Bahoo , Ahmad Kamaludeen

Let $P$ be a set of $n$ points in the plane. We show how to find, for a given integer $k>0$, the smallest-area axis-parallel rectangle that covers $k$ points of $P$ in $O(nk^2 \log n+ n\log^2 n)$ time. We also consider the problem of, given…

Computational Geometry · Computer Science 2019-07-12 Mark de Berg , Sergio Cabello , Otfried Cheong , David Eppstein , Christian Knauer