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Related papers: Approximating the rectilinear crossing number

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The page number of a directed acyclic graph $G$ is the minimum $k$ for which there is a topological ordering of $G$ and a $k$-coloring of the edges such that no two edges of the same color cross, i.e., have alternating endpoints along the…

Combinatorics · Mathematics 2023-05-10 Paul Jungeblut , Laura Merker , Torsten Ueckerdt

An obstacle representation of a graph $G$ consists of a set of pairwise disjoint simply-connected closed regions and a one-to-one mapping of the vertices of $G$ to points such that two vertices are adjacent in $G$ if and only if the line…

Computational Geometry · Computer Science 2025-02-25 Martin Balko , Steven Chaplick , Robert Ganian , Siddharth Gupta , Michael Hoffmann , Pavel Valtr , Alexander Wolff

It is proved that the rectilinear crossing number of every graph with bounded tree-width and bounded degree is linear in the number of vertices. **** This paper has been withdrawn by the author. **** The results have been superseeded by the…

Combinatorics · Mathematics 2007-05-23 David R. Wood

A planar orthogonal drawing {\Gamma} of a connected planar graph G is a geometric representation of G such that the vertices are drawn as distinct points of the plane, the edges are drawn as chains of horizontal and vertical segments, and…

Computational Geometry · Computer Science 2025-02-06 Walter Didimo , Giuseppe Liotta , Giacomo Ortali , Maurizio Patrignani

We consider arbitrary graphs $G$ with $n$ vertices and minimum degree at least $\delta n$ where $\delta>0$ is constant. If the conductance of $G$ is sufficiently large then we obtain an asymptotic expression for the cover time $C_G$ of $G$…

Combinatorics · Mathematics 2019-05-29 Colin Cooper , Alan Frieze , Wesley Pegden

We define the following parameter of connected graphs. For a given graph $G$ we place one agent in each vertex of $G$. Every pair of agents sharing a common edge is declared to be acquainted. In each round we choose some matching of $G$…

Computational Complexity · Computer Science 2014-03-14 Itai Benjamini , Igor Shinkar , Gilad Tsur

Given query access to an undirected graph $G$, we consider the problem of computing a $(1\pm\epsilon)$-approximation of the number of $k$-cliques in $G$. The standard query model for general graphs allows for degree queries, neighbor…

Data Structures and Algorithms · Computer Science 2018-11-13 Talya Eden , Dana Ron , C. Seshadhri

Vizing's theorem states that any graph of maximum degree $\Delta$ can be properly edge colored with at most $\Delta+1$ colors. In the online setting, it has been a matter of interest to find an algorithm that can properly edge color any…

Data Structures and Algorithms · Computer Science 2024-10-30 Aditi Dudeja , Rashmika Goswami , Michael Saks

In 1996, Karger [Kar96] gave a startling randomized algorithm that finds a minimum-cut in a (weighted) graph in time $O(m\log^3n)$ which he termed near-linear time meaning linear (in the size of the input) times a polylogarthmic factor. In…

Data Structures and Algorithms · Computer Science 2024-01-12 Monika Henzinger , Jason Li , Satish Rao , Di Wang

A planar orthogonal drawing $\Gamma$ of a planar graph $G$ is a geometric representation of $G$ such that the vertices are drawn as distinct points of the plane, the edges are drawn as chains of horizontal and vertical segments, and no two…

Data Structures and Algorithms · Computer Science 2019-10-28 Walter Didimo , Giuseppe Liotta , Giacomo Ortali , Maurizio Patrignani

We present a novel approach to graph drawing based on reinforcement learning for minimizing the global and the local crossing number, that is, the total number of edge crossings and the maximum number of crossings on any edge, respectively.…

Computational Geometry · Computer Science 2025-09-09 Timo Brand , Henry Förster , Stephen Kobourov , Robin Schukrafft , Markus Wallinger , Johannes Zink

An orientation of $G$ is a digraph obtained from $G$ by replacing each edge by exactly one of two possible arcs with the same endpoints. We call an orientation \emph{proper} if neighbouring vertices have different in-degrees. The proper…

Combinatorics · Mathematics 2020-03-18 J. Ai , S. Gerke , G. Gutin , Y. Shi , Z. Taoqiu

A path $P$ in an edge-colored graph $G$ is called a proper path if no two adjacent edges of $P$ are colored the same, and $G$ is proper connected if every two vertices of $G$ are connected by a proper path in $G$. The proper connection…

Combinatorics · Mathematics 2015-04-30 Fei Huang , Xueliang Li , Shujing Wang

An equivalence graph is a disjoint union of cliques, and the equivalence number $\mathit{eq}(G)$ of a graph $G$ is the minimum number of equivalence subgraphs needed to cover the edges of $G$. We consider the equivalence number of a line…

Combinatorics · Mathematics 2011-02-16 L. Esperet , J. Gimbel , A. King

Unit edge-length drawings, rectilinear drawings (where each edge is either a horizontal or a vertical segment), and rectangular face drawings are among the most studied subjects in Graph Drawing. However, most of the literature on these…

A simple topological graph T = (V(T), E(T)) is a drawing of a graph in the plane where every two edges have at most one common point (an endpoint or a crossing) and no three edges pass through a single crossing. Topological graphs G and H…

Combinatorics · Mathematics 2022-12-13 Jan Kynčl

An ortho-polygon visibility representation of an $n$-vertex embedded graph $G$ (OPVR of $G$) is an embedding-preserving drawing of $G$ that maps every vertex to a distinct orthogonal polygon and each edge to a vertical or horizontal…

Computational Geometry · Computer Science 2017-05-17 Emilio Di Giacomo , Walter Didimo , William S. Evans , Giuseppe Liotta , Henk Meijer , Fabrizio Montecchiani , Stephen K. Wismath

A new heuristic for rectilinear crossing minimization is proposed. It is based on the idea of iteratively repositioning nodes after a first initial graph drawing. The new position of a node is computed by casting rays from the node towards…

Computational Geometry · Computer Science 2023-04-17 François Doré , Enrico Formenti

We define strict confluent drawing, a form of confluent drawing in which the existence of an edge is indicated by the presence of a smooth path through a system of arcs and junctions (without crossings), and in which such a path, if it…

Computational Geometry · Computer Science 2016-08-12 David Eppstein , Danny Holten , Maarten Löffler , Martin Nöllenburg , Bettina Speckmann , Kevin Verbeek

The determining number of a graph $G = (V,E)$ is the minimum cardinality of a set $S\subseteq V$ such that pointwise stabilizer of $S$ under the action of $Aut(G)$ is trivial. In this paper, we provide some improved upper and lower bounds…

Combinatorics · Mathematics 2023-06-22 Angsuman Das , Hiranya Kishore Dey
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