Results 21 to 30 of about 1,484,168 (305)

Popular Conjectures as a Barrier for Dynamic Planar Graph Algorithms [PDF]

open access: yesIEEE Annual Symposium on Foundations of Computer Science, 2016
The dynamic shortest paths problem on planar graphs asks us to preprocess a planar graph G such that we may support insertions and deletions of edges in G as well as distance queries between any two nodes u, v subject to the constraint that the graph ...
Amir Abboud, Søren Dahlgaard
semanticscholar   +1 more source

A Planarity Criterion for Graphs [PDF]

open access: yesSIAM Journal on Discrete Mathematics, 2015
It is proven that a connected graph is planar if and only if all its cocycles with at least four edges are "grounded" in the graph. The notion of grounding of this planarity criterion, which is purely combinatorial, stems from the intuitive idea that with planarity there should be a linear ordering of the edges of a cocycle such that in the two ...
Kosta Dosen, Zoran Petric
openaire   +4 more sources

Partitioning a triangle-free planar graph into a forest and a forest of bounded degree [PDF]

open access: yesEuropean journal of combinatorics (Print), 2015
An $({\cal F},{\cal F}_d)$-partition of a graph is a vertex-partition into two sets $F$ and $F_d$ such that the graph induced by $F$ is a forest and the one induced by $F_d$ is a forest with maximum degree at most $d$.
François Dross   +2 more
semanticscholar   +1 more source

An SPQR-tree-like embedding representation for level planarity

open access: yesJournal of Computational Geometry, 2023
An SPQR-tree is a data structure that efficiently represents all planar embeddings of a  connected 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 some given set
Guido Brückner, Ignaz Rutter
doaj   +1 more source

The square of a planar cubic graph is 7-colorable [PDF]

open access: yesJ. Comb. Theory B, 2017
We prove the conjecture made by G.Wegner in 1977 that the square of every planar, cubic graph is $7$-colorable. Here, $7$ cannot be replaced by $6$.
C. Thomassen
semanticscholar   +1 more source

Upward Planar Drawings with Three and More Slopes

open access: yesJournal of Graph Algorithms and Applications, 2023
The slope number of a graph $G$ is the smallest number of slopes needed for the segments representing the edges in any straight-line drawing of $G$. It serves as a measure of the visual complexity of a graph drawing.
Jonathan Klawitter, Johannes Zink
doaj   +1 more source

Drawing planar graphs with many collinear vertices

open access: yesJournal of Computational Geometry, 2018
Consider the following problem: Given a planar graph $G$, what is the maximum number $p$ such that $G$ has a planar straight-line drawing with $p$ collinear vertices?
Giordano Da Lozzo   +4 more
doaj   +1 more source

Gap-planar graphs

open access: yesTheoretical Computer Science, 2018
We introduce the family of $k$-gap-planar graphs for $k \geq 0$, i.e., graphs that have a drawing in which each crossing is assigned to one of the two involved edges and each edge is assigned at most $k$ of its crossings. This definition is motivated by applications in edge casing, as a $k$-gap-planar graph can be drawn crossing-free after introducing ...
Sang Won Bae 0001   +10 more
openaire   +5 more sources

Matched Drawings of Planar Graphs

open access: yesJournal of Graph Algorithms and Applications, 2009
A natural way to draw two planar graphs whose vertex sets are matched is to assign each matched pair a unique y-coordinate. In this paper we introduce the concept of such matched drawings, which is a relaxation of simultaneous geometric embeddings with ...
Emilio Di Giacomo   +4 more
doaj   +1 more source

Improved Bounds for Track Numbers of Planar Graphs

open access: yesJournal of Graph Algorithms and Applications, 2020
A track layout of a graph consists of a vertex coloring and a total order of each color class, such that no two edges cross between any two color classes.
Sergey Pupyrev
doaj   +1 more source

Home - About - Disclaimer - Privacy