activity
20092020
most citedCrossing numbers and combinatorial characterization of monotone drawings of

30 citations · 65 across the 19 of their papers we have counts for

collaborators

33 papers

math.CO2020

Saturation problems about forbidden - submatrices

Radoslav Fulek, Balázs Keszegh

A - matrix is saturating for a - matrix if does not contain a submatrix that can be turned into by changing some entries to entries, and changin…

cs.DM2020

Strong Hanani-Tutte for the Torus

Radoslav Fulek, Michael J. Pelsmajer, Marcus Schaefer

If a graph can be drawn on the torus so that every two independent edges cross an even number of times, then the graph can be embedded on the torus.

cs.CG2020

Polygons with Prescribed Angles in 2D and 3D

Alon Efrat, Radoslav Fulek, Stephen Kobourov +1

We consider the construction of a polygon with vertices whose turning angles at the vertices are given by a sequence , , for $i\in\{…

cs.CG2019

Atomic Embeddability, Clustered Planarity, and Thickenability

Radoslav Fulek, Csaba D. Tóth

We study the atomic embeddability testing problem, which is a common generalization of clustered planarity (c-planarity, for short) and thickenability testing, and present a polyno…

math.CO2019

Z_2-genus of graphs and minimum rank of partial symmetric matrices

Radoslav Fulek, Jan Kynčl

The \emph{genus} of a graph is the minimum such that has an embedding on the orientable surface of genus . A drawing of a graph on a surface is…

math.CO2018★ 1 cited

A Note on a Picture-Hanging Puzzle

Radoslav Fulek, Sergey Avvakumov

In the picture-hanging puzzle we are to hang a picture so that the string loops around nails and the removal of any nail results in a fall of the picture. We show that the leng…

cs.CG2018

The Crossing Tverberg Theorem

Radoslav Fulek, Bernd Gärtner, Andrey Kupavskii +2

Tverberg's theorem is one of the cornerstones of discrete geometry. It states that, given a set of at least points in , one can find a partition $X=…

cs.CG2018

Crossing Minimization in Perturbed Drawings

Radoslav Fulek, Csaba D. Tóth

Due to data compression or low resolution, nearby vertices and edges of a graph drawing may be bundled to a common node or arc. We model such a `compromised' drawing by a piecewise…

cs.CG2017

Recognizing Weak Embeddings of Graphs

Hugo A. Akitaya, Radoslav Fulek, Csaba D. Tóth

We present an efficient algorithm for a problem in the interface between clustering and graph embeddings. An embedding of a graph into a 2-manifold maps…

math.CO2017★ 6 cited

Counterexample to an extension of the Hanani-Tutte theorem on the surface of genus 4

Radoslav Fulek, Jan Kynčl

We find a graph of genus and its drawing on the orientable surface of genus with every pair of independent edges crossing an even number of times. This shows that the stron…

math.CO2017

Thrackles: An Improved Upper Bound

Radoslav Fulek, János Pach

A {\em thrackle} is a graph drawn in the plane so that every pair of its edges meet exactly once: either at a common end vertex or in a proper crossing. We prove that any thrackle…

cs.CG2017

Hanani-Tutte for approximating maps of graphs

Radoslav Fulek, Jan Kynčl

We resolve in the affirmative conjectures of Repovs and A. Skopenkov (1998), and M. Skopenkov (2003) generalizing the classical Hanani-Tutte theorem to the setting of approximating…

math.CO2017

On the Existence of Ordinary Triangles

Radoslav Fulek, Hossein Nassajian Mojarrad, Márton Naszódi +3

Let be a finite point set in the plane. A \emph{-ordinary triangle} in is a subset of consisting of three non-collinear points such that each of the three lines dete…

math.CO2016

Unified Hanani-Tutte theorem

Radoslav Fulek, Jan Kynčl, Dömötör Pálvölgyi

We introduce a common generalization of the strong Hanani-Tutte theorem and the weak Hanani-Tutte theorem: if a graph has a drawing in the plane where every pair of indepen…

cs.CG2016

Bounded embeddings of graphs in the plane

Radoslav Fulek

A drawing in the plane () of a graph equipped with a function is \emph{-bounded} if (i) whenever a…

cs.CG2016

Hanani-Tutte for Radial Planarity II

Radoslav Fulek, Michael Pelsmajer, Marcus Schaefer

A drawing of a graph is radial if the vertices of are placed on concentric circles with common center , and edges are drawn radially: every edge inter…

cs.CG2016

Embedding graphs into embedded graphs

Radoslav Fulek

A (possibly denerate) drawing of a graph in the plane is approximable by an embedding if it can be turned into an embedding by an arbitrarily small perturbation. We show that t…

cs.CG2016

C-planarity of Embedded Cyclic c-Graphs

Radoslav Fulek

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 gra…

cs.CG2014★ 4 cited

Toward the Hanani-Tutte Theorem for Clustered Graphs

Radoslav Fulek

The weak variant of Hanani-Tutte theorem says that a graph is planar, if it can be drawn in the plane so that every pair of edges cross an even number of times. Moreover, we can tu…

math.CO2013★ 30 cited

Crossing numbers and combinatorial characterization of monotone drawings of

Martin Balko, Radoslav Fulek, Jan Kynčl

In 1958, Hill conjectured that the minimum number of crossings in a drawing of is exactly $Z(n) = \frac{1}{4} \lfloor\frac{n}{2}\rfloor \left\lfloor\frac{n-1}{2}\right\rfloor…

cs.DM2013

Extending Partial Representations of Circle Graphs

Steven Chaplick, Radoslav Fulek, Pavel Klavík

The partial representation extension problem is a recently introduced generalization of the recognition problem. A circle graph is an intersection graph of chords of a circle. We s…

math.CO2013

Estimating the number of disjoint edges in simple topological graphs via cylindrical drawings

Radoslav Fulek

A topological graph drawn on a cylinder whose base is horizontal is \emph{angularly monotone} if every vertical line intersects every edge at most once. Let denote the maxim…

cs.CG2013

Clustered planarity testing revisited

Radoslav Fulek, Jan Kynčl, Igor Malinović +1

The Hanani--Tutte theorem is a classical result proved for the first time in the 1930s that characterizes planar graphs as graphs that admit a drawing in the plane in which every p…

math.CO2013★ 5 cited

Homometric sets in trees

Radoslav Fulek, Slobodan Mitrović

Let denote a simple graph with the vertex set and the edge set . The profile of a vertex set denotes the multiset of pairwise distances between t…