English
Related papers

Related papers: $1$-String $B_1$-VPG Representations of Planar Par…

200 papers

We prove that every simple polygon contains a degree 3 tree encompassing a prescribed set of vertices. We give tight bounds on the minimal number of degree 3 vertices. We apply this result to reprove a result from Bose et al. that every set…

Computational Geometry · Computer Science 2012-11-12 Tillmann Miltzow

An SPQR-tree is a data structure that efficiently represents all planar embeddings of a biconnected planar graph. It is a key tool in a number of constrained planarity testing algorithms, which seek a planar embedding of a graph subject to…

Data Structures and Algorithms · Computer Science 2020-09-28 Guido Brückner , Ignaz Rutter

A visibility representation of a graph $G$ is an assignment of the vertices of $G$ to geometric objects such that vertices are adjacent if and only if their corresponding objects are "visible" each other, that is, there is an uninterrupted…

Combinatorics · Mathematics 2016-09-06 Eric Peterson , Paul S. Wenger

Given an ordered partition $\Pi =\{P_1,P_2, ...,P_t\}$ of the vertex set $V$ of a connected graph $G=(V,E)$, the \emph{partition representation} of a vertex $v\in V$ with respect to the partition $\Pi$ is the vector…

Combinatorics · Mathematics 2014-02-10 Juan A. Rodriguez-Velazquez , Ismael G. Yero , Magdalena Lemanska

A segment representation of a graph is an assignment of line segments in 2D to the vertices in such a way that two segments intersect if and only if the corresponding vertices are adjacent. Not all graphs have such segment representations,…

Computational Geometry · Computer Science 2018-10-17 Therese Biedl

Every chordal graph $G$ can be represented as the intersection graph of a collection of subtrees of a host tree, a so-called {\em tree model} of $G$. The leafage $\ell(G)$ of a connected chordal graph $G$ is the minimum number of leaves of…

Discrete Mathematics · Computer Science 2015-10-07 Steven Chaplick , Juraj Stacho

In this paper, we prove that every planar 4-connected graph has a CZ-representation---a string representation using paths in a rectangular grid that contain at most one vertical segment. Furthermore, two paths representing vertices $u,v$…

Computational Geometry · Computer Science 2014-09-23 Therese Biedl , Martin Derka

The overlap graphs of subtrees in a tree (SOGs) generalise many other graphs classes with set representation characterisations. The complexity of recognising SOGs in open. The complexities of recognising many subclasses of SOGs are known.…

Computational Complexity · Computer Science 2022-02-04 Jessica Enright , Martin Pergel

In a {\em grounded string representation} of a graph there is a horizontal line $\ell$ and each vertex is represented as a simple curve below $\ell$ with one end point on $\ell$ such that two curves intersect if and only if the respective…

Computational Geometry · Computer Science 2026-03-04 Sabine Cornelsen , Jan Kratochvíl , Miriam Münch , Giacomo Ortali , Alexandra Weinberger , Alexander Wolff

A unit disk intersection representation (UDR) of a graph $G$ represents each vertex of $G$ as a unit disk in the plane, such that two disks intersect if and only if their vertices are adjacent in $G$. A UDR with interior-disjoint disks is…

Computational Geometry · Computer Science 2021-08-27 Sujoy Bhore , Maarten Löffler , Soeren Nickel , Martin Nöllenburg

Reconstruction of evolutionary relationships between species is an important topic in the field of computational biology. Pairwise compatibility graphs (PCGs) are used to model such relationships. A graph is a PCG if its edges can be…

Discrete Mathematics · Computer Science 2024-10-17 Seemab Hayat , Naveed Ahmed Azam

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

An obstacle representation of a graph $G$ consists of a set of polygonal obstacles and a drawing of $G$ as a visibility graph with respect to the obstacles: vertices are mapped to points and edges to straight-line segments such that each…

Computational Geometry · Computer Science 2025-02-18 Oksana Firman , Philipp Kindermann , Jonathan Klawitter , Boris Klemz , Felix Klesen , Alexander Wolff

A $k$-bend path is a non-self-intersecting polyline in the plane made of at most $k+1$ axis-parallel line segments. B$_k$-VPG is the class of graphs which can be represented as intersection graphs of $k$-bend paths in the same plane. In…

Combinatorics · Mathematics 2023-03-07 Sparsh Jain , Sreejith K. Pallathumadam , Deepak Rajendraprasad

If a graph $G$ can be represented by means of paths on a grid, such that each vertex of $G$ corresponds to one path on the grid and two vertices of $G$ are adjacent if and only if the corresponding paths share a grid edge, then this graph…

Combinatorics · Mathematics 2023-06-06 Eranda Çela , Elisabeth Gaar

We introduce and study the 1-planar packing problem: Given $k$ graphs with $n$ vertices $G_1, \dots, G_k$, find a 1-planar graph that contains the given graphs as edge-disjoint spanning subgraphs. We mainly focus on the case when each $G_i$…

We consider drawings of graphs that contain dense subgraphs. We introduce intersection-link representations for such graphs, in which each vertex $u$ is represented by a geometric object $R(u)$ and in which each edge $(u,v)$ is represented…

Data Structures and Algorithms · Computer Science 2015-09-01 Patrizio Angelini , Giordano Da Lozzo , Giuseppe Di Battista , Fabrizio Frati , Maurizio Patrignani , Ignaz Rutter

Motivated by dynamic graph visualization, we study the problem of representing a graph $G$ in the form of a \emph{storyplan}, that is, a sequence of frames with the following properties. Each frame is a planar drawing of the subgraph of $G$…

In this paper we continue the study of the edge intersection graphs of one (or zero) bend paths on a rectangular grid. That is, the edge intersection graphs where each vertex is represented by one of the following shapes:…

Discrete Mathematics · Computer Science 2015-10-06 Kathie Cameron , Steven Chaplick , Chính T. Hoàng

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