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Related papers: Point Location in Incremental Planar Subdivisions

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We study the point location problem on dynamic planar subdivisions that allows insertions and deletions of edges. In our problem, the underlying graph of a subdivision is not necessarily connected. We present a data structure of linear size…

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

In this paper we describe a fully-dynamic data structure for the planar point location problem in the external memory model. Our data structure supports queries in $O(\log_B n(\log\log_B n)^3))$ I/Os and updates in $O(\log_B n(\log\log_B…

Data Structures and Algorithms · Computer Science 2019-03-18 J. Ian Munro , Yakov Nekrich

We study dynamic planar point location in the External Memory Model or Disk Access Model (DAM). Previous work in this model achieves polylog query and polylog amortized update time. We present a data structure with $O( \log_B^2 N)$ query…

Data Structures and Algorithms · Computer Science 2022-03-31 John Iacono , Ben Karsin , Grigorios Koumoutsos

Let $G$ be a (possibly disconnected) planar subdivision and let $D$ be a probability measure over $\R^2$. The current paper shows how to preprocess $(G,D)$ into an O(n) size data structure that can answer planar point location queries over…

Computational Geometry · Computer Science 2010-01-18 Prosenjit Bose , Luc Devroye , Karim Douieb , Vida Dujmovic , James King , Pat Morin

An arrangement of $n$ curves in the plane is given. The query is a point $q$ and the goal is to find the face of the arrangement that contains $q$. A data-structure for point-location, preprocesses the curves into a data structure of…

Computational Geometry · Computer Science 2020-12-07 Sepideh Aghamolaei , Mohammad Ghodsi

We propose a dynamic data structure for the distribution-sensitive point location problem. Suppose that there is a fixed query distribution in $\mathbb{R}^2$, and we are given an oracle that can return in $O(1)$ time the probability of a…

Computational Geometry · Computer Science 2020-04-28 Siu-Wing Cheng , Man-Kit Lau

Given a planar map of $n$ segments in which we wish to efficiently locate points, we present the first randomized incremental construction of the well-known trapezoidal-map search-structure that only requires expected $O(n \log n)$…

Computational Geometry · Computer Science 2014-10-22 Michael Hemmer , Michal Kleinbort , Dan Halperin

For a set $P$ of $n$ points in the plane and a value $r > 0$, the unit-disk range reporting problem is to construct a data structure so that given any query disk of radius $r$, all points of $P$ in the disk can be reported efficiently. We…

Computational Geometry · Computer Science 2025-01-03 Haitao Wang , Yiming Zhao

In this article, we determine the amortized computational complexity of the planar dynamic convex hull problem by querying. We present a data structure that maintains a set of n points in the plane under the insertion and deletion of points…

Computational Geometry · Computer Science 2019-03-01 Riko Jacob , Gerth Stølting Brodal

We present self-adjusting data structures for answering point location queries in convex and connected subdivisions. Let $n$ be the number of vertices in a convex or connected subdivision. Our structures use $O(n)$ space. For any convex…

Computational Geometry · Computer Science 2018-10-02 Siu-Wing Cheng , Man-Kit Lau

This paper considers fully dynamic graph algorithms with both faster worst case update time and sublinear space. The fully dynamic graph connectivity problem is the following: given a graph on a fixed set of n nodes, process an online…

Data Structures and Algorithms · Computer Science 2015-09-23 David Gibb , Bruce Kapron , Valerie King , Nolan Thorn

In this paper we show a new algorithm for the decremental single-source reachability problem in directed planar graphs. It processes any sequence of edge deletions in $O(n\log^2{n}\log\log{n})$ total time and explicitly maintains the set of…

Data Structures and Algorithms · Computer Science 2017-06-01 Giuseppe F. Italiano , Adam Karczmarz , Jakub Łącki , Piotr Sankowski

We preprocess the input subdivision with $n$ points on the plane in $O(n\sqrt{\log n})$ time to facilitate point location in constant time. Previously the preprocessing time is $O(n\log n)$ and point location takes $O(\log n)$ time.

Computational Geometry · Computer Science 2024-01-08 Sairam Chaganti , Yijie Han

In this paper we show that two-dimensional nearest neighbor queries can be answered in optimal $O(\log n)$ time while supporting insertions in $O(\log^{1+\varepsilon}n)$ time. No previous data structure was known that supports $O(\log…

Data Structures and Algorithms · Computer Science 2025-04-11 John Iacono , Yakov Nekrich

We study dynamic planar graphs with $n$ vertices, subject to edge deletion, edge contraction, edge insertion across a face, and the splitting of a vertex in specified corners. We dynamically maintain a combinatorial embedding of such a…

Data Structures and Algorithms · Computer Science 2022-09-29 Jacob Holm , Ivor van der Hoog , Eva Rotenberg

A data structure is presented that explicitly maintains the graph of a Voronoi diagram of $N$ point sites in the plane or the dual graph of a convex hull of points in three dimensions while allowing insertions of new sites/points. Our…

Computational Geometry · Computer Science 2020-07-06 Elena Arseneva , John Iacono , Grigorios Koumoutsos , Stefan Langerman , Boris Zolotov

We present a major revamp of the point-location data structure for general two-dimensional subdivisions via randomized incremental construction, implemented in CGAL, the Computational Geometry Algorithms Library. We can now guarantee that…

Computational Geometry · Computer Science 2015-09-17 Michael Hemmer , Michal Kleinbort , Dan Halperin

Given a dynamic graph subject to insertions and deletions of edges, a natural question is whether the graph presently admits a planar embedding. We give a deterministic fully-dynamic algorithm for general graphs, running in amortized…

Data Structures and Algorithms · Computer Science 2019-12-11 Jacob Holm , Eva Rotenberg

We study planar point location in a collection of disjoint fat regions, and investigate the complexity of \emph {local updates}: replacing any region by a different region that is "similar" to the original region. (i.e., the size differs by…

Computational Geometry · Computer Science 2013-02-26 Maarten Löffler , Joe Simons , Darren Strash

We show an algorithm for dynamic maintenance of connectivity information in an undirected planar graph subject to edge deletions. Our algorithm may answer connectivity queries of the form `Are vertices $u$ and $v$ connected with a path?' in…

Data Structures and Algorithms · Computer Science 2014-09-26 Jakub Łącki , Piotr Sankowski
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