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Related papers: Drawing outer-1-planar graphs revisited

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A straight-line drawing $\delta$ of a planar graph $G$ need not be plane, but can be made so by \emph{untangling} it, that is, by moving some of the vertices of $G$. Let shift$(G,\delta)$ denote the minimum number of vertices that need to…

Computational Geometry · Computer Science 2009-01-27 Xavier Goaoc , Jan Kratochvil , Yoshio Okamoto , Chan-Su Shin , Andreas Spillner , Alexander Wolff

In this paper, we consider the problem of representing graphs by polygons whose sides touch. We show that at least six sides per polygon are necessary by constructing a class of planar graphs that cannot be represented by pentagons. We also…

Computational Geometry · Computer Science 2015-03-19 Christian A. Duncan , Emden R. Gansner , Yifan Hu , Michael Kaufmann , Stephen G. Kobourov

We prove polynomial upper bounds of geometric Ramsey numbers of pathwidth-2 outerplanar triangulations in both convex and general cases. We also prove that the geometric Ramsey numbers of the ladder graph on $2n$ vertices are bounded by…

Combinatorics · Mathematics 2015-09-14 Josef Cibulka , Pu Gao , Marek Krčál , Tomáš Valla , Pavel Valtr

Graph Drawing Beyond Planarity is a rapidly growing research area that classifies and studies geometric representations of non-planar graphs in terms of forbidden crossing configurations. Aim of this survey is to describe the main research…

Computational Geometry · Computer Science 2019-09-04 Walter Didimo , Giuseppe Liotta , Fabrizio Montecchiani

A plane graph is rectilinear planar if it admits an embedding-preserving straight-line drawing where each edge is either horizontal or vertical. We prove that rectilinear planarity testing can be solved in optimal $O(n)$ time for any plane…

Data Structures and Algorithms · Computer Science 2021-03-01 Walter Didimo , Michael Kaufmann , Giuseppe Liotta , Giacomo Ortali

We calculate the outerplanar crossing numbers of complete multipartite graphs which have $n$ partite sets with $m$ vertices and one partite set with $p$ vertices, where either $p|mn$ or $mn|p$.

Combinatorics · Mathematics 2007-05-23 Adrian Riskin

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

In this paper we study the area requirements of planar greedy drawings of triconnected planar graphs. Cao, Strelzoff, and Sun exhibited a family $\cal H$ of subdivisions of triconnected plane graphs and claimed that every planar greedy…

Computational Geometry · Computer Science 2020-03-04 Giordano Da Lozzo , Anthony D'Angelo , Fabrizio Frati

Deciding whether a given graph has a square root is a classical problem that has been studied extensively both from graph theoretic and from algorithmic perspectives. The problem is NP-complete in general, and consequently substantial…

Data Structures and Algorithms · Computer Science 2018-10-09 Petr A. Golovach , Pinar Heggernes , Dieter Kratsch , Paloma T. Lima , Daniel Paulusma

Modern methods of graph theory describe a graph up to isomorphism, which makes it difficult to create mathematical models for visualizing graph drawings on a plane. The topological drawing of the planar part of a graph allows representing…

Combinatorics · Mathematics 2024-08-01 Sergey Kurapov , Maxim Davidovsky

We study a variant of intersection representations with unit balls, that is, unit disks in the plane and unit intervals on the line. Given a planar graph and a bipartition of the edges of the graph into near and far sets, the goal is to…

Discrete Mathematics · Computer Science 2014-09-01 Md. Jawaherul Alam , Stephen G. Kobourov , Sergey Pupyrev , Jackson Toeniskoetter

A drawing of a graph is fan-planar if the edges intersecting a common edge $a$ share a vertex $A$ on the same side of $a$. More precisely, orienting $e$ arbitrarily and the other edges towards $A$ results in a consistent orientation of the…

Computational Geometry · Computer Science 2021-08-31 Boris Klemz , Kristin Knorr , Meghana M. Reddy , Felix Schröder

In this paper, we give polynomial-time algorithms that can take a graph G with a given combinatorial embedding on an orientable surface S of genus g and produce a planar drawing of G in R^2, with a bounding face defined by a polygonal…

Computational Geometry · Computer Science 2009-08-13 Christian A. Duncan , Michael T. Goodrich , Stephen G. Kobourov

The k-planar graphs, which are (usually with small values of k such as 1, 2, 3) subject to recent intense research, admit a drawing in which edges are allowed to cross, but each one edge is allowed to carry at most k crossings. In recently…

Combinatorics · Mathematics 2024-10-02 Petr Hliněný , Lili Ködmön

Calculating the diameter of an undirected graph requires quadratic running time under the Strong Exponential Time Hypothesis and this barrier works even against any approximation better than 3/2. For planar graphs with positive edge…

Data Structures and Algorithms · Computer Science 2025-07-08 Michał Włodarczyk

A graph $G=(V,E)$ is called 1-planar if it admits a drawing in the plane such that each edge is crossed at most once. In this paper, we study bipartite $1$-planar graphs with prescribed numbers of vertices in partite sets. Bipartite…

Combinatorics · Mathematics 2015-03-05 Július Czap , Jakub Przybyło , Erika Škrabuľáková

We show that there are $O(n \cdot 4^{n/11})$ planar graphs on $n$ vertices which do not admit a simultaneous straight-line embedding on any $n$-point set in the plane. In particular, this improves the best known bound $O(n!)$ significantly.

Combinatorics · Mathematics 2023-10-26 Ritesh Goenka , Pardis Semnani , Chi Hoi Yip

There is a graph reduction system so that every optimal 1-planar graph can be reduced to an irreducible extended wheel graph, provided the reductions are applied such that the given graph class is preserved. A graph is optimal 1-planar if…

Computational Geometry · Computer Science 2016-10-28 Franz J. Brandenburg

We consider the problem of computing 2-center in maximal outerplanar graph. In this problem, we want to find an optimal solution where two centers cover all the vertices with the smallest radius. We provide the following result. We can…

Combinatorics · Mathematics 2022-08-09 Hsiu-Fu Yeh

We study straight-line drawings of planar graphs with few segments and few slopes. Optimal results are obtained for all trees. Tight bounds are obtained for outerplanar graphs, 2-trees, and planar 3-trees. We prove that every 3-connected…

Combinatorics · Mathematics 2008-09-09 Vida Dujmovic' , David Eppstein , Matthew Suderman , David R. Wood
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