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Related papers: Computing k-Modal Embeddings of Planar Digraphs

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A map is a partition of the sphere into regions that are labeled as countries or holes. The vertices of a map graph are the countries of a map. There is an edge if and only if the countries are adjacent and meet in at least one point. For a…

Computational Geometry · Computer Science 2023-08-23 Franz J. Brandenburg

Given a planar graph $G$ and a partition of the neighbors of each vertex $v$ in four sets $UR(v)$, $UL(v)$, $DL(v)$, and $DR(v)$, the problem Windrose Planarity asks to decide whether $G$ admits a windrose-planar drawing, that is, a planar…

Let $G$ be a graph with vertex set V and edge set E such that |V| = p and |E| = q. For integers k\geq 0, define an edge labeling f : E \rightarrow \{k,k+1,....,k+q-1\} and define the vertex sum for a vertex $v$ as the sum of the labels of…

Combinatorics · Mathematics 2012-07-16 Sin-Min Lee , Saeid Alikhani , Gee-Choon Lau , William Kocay

In this article we describe the $G_{comp}\times G_{comp}$-equivariant topological $K$-ring of a {\em cellular} toroidal embedding $\mathbb{X}$ of a complex connected reductive algebraic group $G$. In particular, our results extend the…

Algebraic Geometry · Mathematics 2025-06-11 Alexis Tchoudjem , V. Uma

We show that c-planarity is solvable in quadratic time for flat clustered graphs with three clusters if the combinatorial embedding of the underlying graph is fixed. In simpler graph-theoretical terms our result can be viewed as follows.…

Computational Geometry · Computer Science 2016-08-26 Radoslav Fulek

A graph is called (generically) rigid in $\mathbb{R}^d$ if, for any choice of sufficiently generic edge lengths, it can be embedded in $\mathbb{R}^d$ in a finite number of distinct ways, modulo rigid transformations. Here we deal with the…

Computational Geometry · Computer Science 2017-01-26 Ioannis Z. Emiris , Ioannis Psarros

Let $G=(V,E)$ be a graph of order $n$ and let $1\leq k< n$ be an integer. The $k$-token graph of $G$ is the graph whose vertices are all the $k$-subsets of $V$, two of which are adjacent whenever their symmetric difference is a pair of…

Combinatorics · Mathematics 2018-02-21 Walter Carballosa , Ruy Fabila-Monroy , Jesús Leaños , Luis Manuel Rivera

Building on work of the first and last author, we prove that an embedding of simple affine vertex algebras $V_{\mathbf{k}}(\mathfrak g^0)\subset V_{k}(\mathfrak g)$, corresponding to an embedding of a maximal equal rank reductive subalgebra…

Representation Theory · Mathematics 2018-02-09 Drazen Adamovic , Victor G. Kac , Pierluigi Moseneder Frajria , Paolo Papi , Ozren Perse

Planarity Testing is the problem of determining whether a given graph is planar while planar embedding is the corresponding construction problem. The bounded space complexity of these problems has been determined to be exactly Logspace by…

Computational Complexity · Computer Science 2015-03-17 Samir Datta , Gautam Prakriya

A $k$-modal sequence is a sequence of real numbers that can be partitioned into $k+1$ (possibly empty) monotone sections such that adjacent sections have opposite monotonicities. For every positive integer $k$, we prove that any sequence of…

Combinatorics · Mathematics 2024-03-21 Zijian Xu

A general position map $f:K\to M$ of a $k$-dimensional simplicial complex to a $2k$-dimensional manifold (for $k=1$, of a graph to a surface) is a $\mathbb Z_2$-embedding if $|f\sigma \cap f\tau|$ is even for any non-adjacent $k$-faces…

Geometric Topology · Mathematics 2026-02-27 A. Skopenkov , O. Styrt

For each k greater than or equal to 5, we construct a modular operad of "k-log-canonically embedded" curves.

Algebraic Geometry · Mathematics 2017-03-29 Satoshi Kondo , Charles Siegel , Jesse Wolfson

In 1999, Heath, Pemmaraju, and Trenk [SIAM J. Comput. 28(4), 1999] extended the classic notion of book embeddings to digraphs, introducing the concept of upward book embeddings, in which the vertices must appear along the spine in a…

Data Structures and Algorithms · Computer Science 2026-03-19 Giordano Da Lozzo , Fabrizio Frati , Ignaz Rutter

An embedding of a graph in a book, called book embedding, consists of a linear ordering of its vertices along the spine of the book and an assignment of its edges to the pages of the book, so that no two edges on the same page cross. The…

A $k$-star is a complete bipartite graph $K_{1,k}$. For a graph $G$, a $k$-star decomposition of $G$ is a set of $k$-stars in $G$ whose edge sets partition the edge set of $G$. If we weaken this condition to only demand that each edge of…

Combinatorics · Mathematics 2021-09-29 Ajani De Vas Gunasekara , Daniel Horsley

Fan-planar graphs were recently introduced as a generalization of 1-planar graphs. A graph is fan-planar if it can be embedded in the plane, such that each edge that is crossed more than once, is crossed by a bundle of two or more edges…

Computational Geometry · Computer Science 2014-09-02 Michael A. Bekos , Sabine Cornelsen , Luca Grilli , Seok-Hee Hong , Michael Kaufmann

Hierarchical embedding constraints define a set of allowed cyclic orders for the edges incident to the vertices of a graph. These constraints are expressed in terms of FPQ-trees. FPQ-trees are a variant of PQ-trees that includes F-nodes in…

Data Structures and Algorithms · Computer Science 2019-11-19 Giuseppe Liotta , Ignaz Rutter , Alessandra Tappini

We introduce and study the problem \mpd, which asks for two planar graphs $G_1$ and $G_2$ whether $G_1$ can be embedded such that its dual is isomorphic to $G_2$. Our algorithmic main result is an NP-completeness proof for the general case…

Data Structures and Algorithms · Computer Science 2013-03-08 Patrizio Angelini , Thomas Bläsius , Ignaz Rutter

We present a new model for hybrid planarity that relaxes existing hybrid representations. A graph $G = (V,E)$ is $(k,p)$-planar if $V$ can be partitioned into clusters of size at most $k$ such that $G$ admits a drawing where: (i) each…

Data Structures and Algorithms · Computer Science 2018-09-25 Emilio Di Giacomo , William J. Lenhart , Giuseppe Liotta , Timothy W. Randolph , Alessandra Tappini

Two planar graphs G1 and G2 sharing some vertices and edges are `simultaneously planar' if they have planar drawings such that a shared vertex [edge] is represented by the same point [curve] in both drawings. It is an open problem whether…

Data Structures and Algorithms · Computer Science 2011-12-12 Bernhard Haeupler , Krishnam Raju Jampani , Anna Lubiw