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Related papers: O(1)-Distortion Planar Emulators for String Graphs

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We prove that for every countable string graph $S$, there is a planar graph $G$ with $V(G)=V(S)$ such that \[ \frac{1}{23660800}d_S(u,v) \le d_G(u,v) \le 162 d_S(u,v) \] for all $u,v\in V(S)$, where $d_S(u,v)$, $d_G(u,v)$ denotes the…

Combinatorics · Mathematics 2026-04-03 James Davies

We show that there exists an adjacency labelling scheme for planar graphs where each vertex of an $n$-vertex planar graph $G$ is assigned a $(1+o(1))\log_2 n$-bit label and the labels of two vertices $u$ and $v$ are sufficient to determine…

Data Structures and Algorithms · Computer Science 2021-12-03 Vida Dujmović , Louis Esperet , Gwenaël Joret , Cyril Gavoille , Piotr Micek , Pat Morin

In this paper, we prove that every planar graph has a 1-string $B_2$-VPG representation---a string representation using paths in a rectangular grid that contain at most two bends. Furthermore, two paths representing vertices $u,v$ intersect…

Computational Geometry · Computer Science 2015-12-04 Therese Biedl , Martin Derka

We study vertex sparsification for distances, in the setting of planar graphs with distortion: Given a planar graph $G$ (with edge weights) and a subset of $k$ terminal vertices, the goal is to construct an $\varepsilon$-emulator, which is…

Data Structures and Algorithms · Computer Science 2022-06-23 Hsien-Chih Chang , Robert Krauthgamer , Zihan Tan

Given a graph $G$ and a set of terminals $T$, a \emph{distance emulator} of $G$ is another graph $H$ (not necessarily a subgraph of $G$) containing $T$, such that all the pairwise distances in $G$ between vertices of $T$ are preserved in…

Data Structures and Algorithms · Computer Science 2018-07-05 Hsien-Chih Chang , Paweł Gawrychowski , Shay Mozes , Oren Weimann

For every $r\ge13$, we show every 1-planar graph $G$ with $\Delta(G)\le r$ has an equitable $r$-coloring.

Combinatorics · Mathematics 2024-12-06 Daniel Cranston , Reem Mahmoud

We prove that every graph has a spectral sparsifier with a number of edges linear in its number of vertices. As linear-sized spectral sparsifiers of complete graphs are expanders, our sparsifiers of arbitrary graphs can be viewed as…

Data Structures and Algorithms · Computer Science 2024-06-01 Joshua Batson , Daniel A. Spielman , Nikhil Srivastava

Given an undirected unweighted graph $G = (V, E)$ on $n$ vertices and $m$ edges, a subgraph $H\subseteq G$ is a spanner of $G$ with stretch function $f: \mathbb{R}_+ \rightarrow \mathbb{R}_+$, if for every pair $s, t$ of vertices in $V$,…

Data Structures and Algorithms · Computer Science 2024-10-18 Zihan Tan , Tianyi Zhang

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

We show that for any constant $\Delta \ge 2$, there exists a graph $G$ with $O(n^{\Delta / 2})$ vertices which contains every $n$-vertex graph with maximum degree $\Delta$ as an induced subgraph. For odd $\Delta$ this significantly improves…

Combinatorics · Mathematics 2019-02-20 Noga Alon , Rajko Nenadov

In this work, we study how far one can deviate from optimal behavior when embedding a planar graph. For a planar graph $G$, we say that a plane subgraph $H\subseteq G$ is a \textit{plane-saturated subgraph} if adding any edge (possibly with…

Combinatorics · Mathematics 2024-03-06 Alexander Clifton , Nika Salia

Spectral graph sparsification has emerged as a powerful tool in the analysis of large-scale networks by reducing the overall number of edges, while maintaining a comparable graph Laplacian matrix. In this paper, we present an efficient…

Data Structures and Algorithms · Computer Science 2014-12-16 David G. Anderson , Ming Gu , Christopher Melgaard

We show that for every integer $n\geq 1$ there exists a graph $G_n$ with $(1+o(1))n$ vertices and $n^{1 + o(1)}$ edges such that every $n$-vertex planar graph is isomorphic to a subgraph of $G_n$. The best previous bound on the number of…

Combinatorics · Mathematics 2023-10-09 Louis Esperet , Gwenaël Joret , Pat Morin

This paper considers 1-string representations of planar graphs that are order-preserving in the sense that the order of crossings along the curve representing vertex $v$ is the same as the order of edges in the clockwise order around $v$ in…

Computational Geometry · Computer Science 2016-09-27 Therese Biedl , Martin Derka

We prove that every $n$-vertex $K_t$-minor-free graph $G$ of maximum degree $\Delta$ has a set $F$ of $O(t^2(\log t)^{1/4}\sqrt{\Delta n})$ edges such that every component of $G - F$ has at most $n/2$ vertices. This is best possible up to…

Combinatorics · Mathematics 2023-10-24 Gwenaël Joret , William Lochet , Michał T. Seweryn

While research on the geometry of planar graphs has been active in the past decades, many properties of planar metrics remain mysterious. This paper studies a fundamental aspect of the planar graph geometry: covering planar metrics by a…

Data Structures and Algorithms · Computer Science 2023-11-07 Hsien-Chih Chang , Jonathan Conroy , Hung Le , Lazar Milenkovic , Shay Solomon , Cuong Than

We prove that, given two topologically-equivalent upward planar straight-line drawings of an $n$-vertex directed graph $G$, there always exists a morph between them such that all the intermediate drawings of the morph are upward planar and…

Data Structures and Algorithms · Computer Science 2018-10-15 Giordano Da Lozzo , Giuseppe Di Battista , Fabrizio Frati , Maurizio Patrignani , Vincenzo Roselli

We prove that if an $n$-vertex graph $G$ can be drawn in the plane such that each pair of crossing edges is independent and there is a crossing-free edge that connects their endpoints, then $G$ has $O(n)$ edges. Graphs that admit such…

Combinatorics · Mathematics 2016-08-31 Eyal Ackerman , Balázs Keszegh , Mate Vizer

A strict orthogonal drawing of a graph $G=(V, E)$ in $\mathbb{R}^2$ is a drawing of $G$ such that each vertex is mapped to a distinct point and each edge is mapped to a horizontal or vertical line segment. A graph $G$ is $HV$-restricted if…

Computational Geometry · Computer Science 2019-04-16 Stephane Durocher , Stefan Felsner , Saeed Mehrabi , Debajyoti Mondal

A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by no more than one other edge (and any pair of crossing edges cross only once). A non-1-planar graph $G$ is minimal if the graph $G-e$ is 1-planar for every…

Combinatorics · Mathematics 2011-10-24 Vladimir P. Korzhik , Bojan Mohar
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