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Related papers: Upward Point Set Embeddings of Paths and Trees

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We discuss the problem of embedding graphs in the plane with restrictions on the vertex mapping. In particular, we introduce a technique for drawing planar graphs with a fixed vertex mapping that bounds the number of times edges bend. An…

Computational Geometry · Computer Science 2012-06-05 Taylor Gordon

Suppose that each proper subset of a set $S$ of points in a vector space is contained in the union of planes of specified dimensions, but $S$ itself is not contained in any such union. How large can $|S|$ be? We prove a general upper bound…

Combinatorics · Mathematics 2025-02-14 Hailong Dao , Manik Dhar , Izabella Łaba , Ben Lund

For a set $P$ of $n$ points in the plane in general position, a non-crossing spanning tree is a spanning tree of the points where every edge is a straight-line segment between a pair of points and no two edges intersect except at a common…

In this paper we study a maximization version of the classical Edge Dominating Set (EDS) problem, namely, the Upper EDS problem, in the realm of Parameterized Complexity. In this problem, given an undirected graph $G$, a positive integer…

Data Structures and Algorithms · Computer Science 2022-08-05 Ajinkya Gaikwad , Soumen Maity

In this paper we study the computational complexity of the Upward Planarity Extension problem, which takes in input an upward planar drawing $\Gamma_H$ of a subgraph $H$ of a directed graph $G$ and asks whether $\Gamma_H$ can be extended to…

Data Structures and Algorithms · Computer Science 2019-02-19 Giordano Da Lozzo , Giuseppe Di Battista , Fabrizio Frati

We prove a fix point theorem for monoids of self-embeddings of trees. As a corollary, we obtain a result by Laflamme, Pouzet and Sauer that a tree either contains a subdivided binary tree as a subtree or has a vertex, and edge, an end or…

Combinatorics · Mathematics 2017-09-19 Matthias Hamann

Let $S$ be a point set in the plane, $\mathcal{P}(S)$ and $\mathcal{C}(S)$ sets of all plane spanning paths and caterpillars on $S$. We study reconfiguration operations on $\mathcal{P}(S)$ and $\mathcal{C}(S)$. In particular, we prove that…

Combinatorics · Mathematics 2024-10-11 Todor Antić , Guillermo Gamboa Quintero , Jelena Glišić

We prove that every set $\mathcal S$ of $\Delta$ slopes containing the horizontal slope is universal for $1$-bend upward planar drawings of bitonic $st$-graphs with maximum vertex degree $\Delta$, i.e., every such digraph admits a $1$-bend…

Computational Geometry · Computer Science 2018-08-30 Michael A. Bekos , Emilio Di Giacomo , Walter Didimo , Giuseppe Liotta , Fabrizio Montecchiani

A finite set $P$ of points in the plane is $n$-universal with respect to a class $\mathcal{C}$ of planar graphs if every $n$-vertex graph in $\mathcal{C}$ admits a crossing-free straight-line drawing with vertices at points of $P$. For the…

Computational Geometry · Computer Science 2023-03-02 Stefan Felsner , Hendrik Schrezenmaier , Felix Schröder , Raphael Steiner

Set membership of points in the plane can be visualized by connecting corresponding points via graphical features, like paths, trees, polygons, ellipses. In this paper we study the \emph{bus embeddability problem} (BEP): given a set of…

Computational Geometry · Computer Science 2015-08-28 Till Bruckdorfer , Michael Kaufmann , Stephen Kobourov , Sergey Pupyrev

We study $k$-page upward book embeddings ($k$UBEs) of $st$-graphs, that is, book embeddings of single-source single-sink directed acyclic graphs on $k$ pages with the additional requirement that the vertices of the graph appear in a…

Computational Geometry · Computer Science 2019-03-20 Carla Binucci , Giordano Da Lozzo , Emilio Di Giacomo , Walter Didimo , Tamara Mchedlidze , Maurizio Patrignani

Given a set of points in the plane, the \textsc{General Position Subset Selection} problem is that of finding a maximum-size subset of points in general position, i.e., with no three points collinear. The problem is known to be ${\rm…

Computational Geometry · Computer Science 2025-04-01 Adrian Dumitrescu

We consider problems in which a simple path of fixed length, in an undirected graph, is to be shifted from a start position to a goal position by moves that add an edge to either end of the path and remove an edge from the other end. We…

Data Structures and Algorithms · Computer Science 2019-05-03 Erik D. Demaine , David Eppstein , Adam Hesterberg , Kshitij Jain , Anna Lubiw , Ryuhei Uehara , Yushi Uno

Let $P$ be a set of $n$ points in the plane in general position. We show that at least $\lfloor n/3\rfloor$ plane spanning trees can be packed into the complete geometric graph on $P$. This improves the previous best known lower bound…

Computational Geometry · Computer Science 2019-02-26 Ahmad Biniaz , Alfredo García

Given a finite set $ S $ of points, we consider the following reconfiguration graph. The vertices are the plane spanning paths of $ S $ and there is an edge between two vertices if the two corresponding paths differ by two edges (one…

Computational Geometry · Computer Science 2024-07-02 Valentino Boucard , Guilherme D. da Fonseca , Bastien Rivier

Given a graph $ G $ with $ n $ vertices and a set $ S $ of $ n $ points in the plane, a point-set embedding of $ G $ on $ S $ is a planar drawing such that each vertex of $ G $ is mapped to a distinct point of $ S $. A straight-line…

Computational Geometry · Computer Science 2017-08-07 Hamid Hoorfar , Alireza Bagheri

We consider the following problem: Given a set $S$ of $n$ distinct points in the plane, how many edge-disjoint plane straight-line spanning paths can be drawn on $S$? Each spanning path must be crossing-free, but edges from different paths…

Computational Geometry · Computer Science 2025-06-10 Philipp Kindermann , Jan Kratochvíl , Giuseppe Liotta , Pavel Valtr

In response to a well-known open question ``Does every complete geometric graph on $2n\/$ vertices have a partition of its edge set into $n\/$ plane spanning trees?" we provide an affirmative answer when the complete geometry graph is in…

Combinatorics · Mathematics 2019-06-14 Hazim Michman Trao , Gek L. Chia , Niran Abbas Ali , Adem Kilicman

Simultaneous Embedding with Fixed Edges (SEFE) is a problem where given $k$ planar graphs we ask whether they can be simultaneously embedded so that the embedding of each graph is planar and common edges are drawn the same. Problems of SEFE…

Discrete Mathematics · Computer Science 2017-12-04 Matěj Konečný , Stanislav Kučera , Jana Novotná , Jakub Pekárek , Martin Smolík , Jakub Tětek , Martin Töpfer

We investigate which planar point sets allow simultaneous straight-line embeddings of all planar graphs on a fixed number of vertices. We first show that $(1.293-o(1))n$ points are required to find a straight-line drawing of each $n$-vertex…

Combinatorics · Mathematics 2019-09-26 Manfred Scheucher , Hendrik Schrezenmaier , Raphael Steiner