On the Planar Split Thickness of Graphs

  • David Eppstein
  • Philipp Kindermann
  • Stephen Kobourov
  • Giuseppe Liotta
  • Anna Lubiw
  • Aude Maignan
  • Debajyoti MondalEmail author
  • Hamideh Vosoughpour
  • Sue Whitesides
  • Stephen Wismath
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9644)


Motivated by applications in graph drawing and information visualization, we examine the planar split thickness of a graph, that is, the smallest k such that the graph is k-splittable into a planar graph. A k-split operation substitutes a vertex v by at most k new vertices such that each neighbor of v is connected to at least one of the new vertices.

We first examine the planar split thickness of complete and complete bipartite graphs. We then prove that it is NP-hard to recognize graphs that are 2-splittable into a planar graph, and show that one can approximate the planar split thickness of a graph within a constant factor. If the treewidth is bounded, then we can even verify k-splittablity in linear time, for a constant k.



Most of the results of this paper were obtained at the McGill-INRIA-Victoria Workshop on Computational Geometry, Barbados, February 2015. We would like to thank the organizers of these events, as well as many participants for fruitful discussions and suggestions. The first, fourth, sixth, and eighth authors acknowledge the support from NSF grant 1228639, 2012C4E3KT PRIN Italian National Research Project, PEPS egalite project, and NSERC respectively.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • David Eppstein
    • 1
  • Philipp Kindermann
    • 2
  • Stephen Kobourov
    • 3
  • Giuseppe Liotta
    • 4
  • Anna Lubiw
    • 5
  • Aude Maignan
    • 6
  • Debajyoti Mondal
    • 7
    Email author
  • Hamideh Vosoughpour
    • 5
  • Sue Whitesides
    • 8
  • Stephen Wismath
    • 9
  1. 1.University of CaliforniaIrvineUSA
  2. 2.FernUniversität HagenHagenGermany
  3. 3.University of ArizonaTucsonUSA
  4. 4.Università Degli Studi di PerugiaPerugiaItaly
  5. 5.University of WaterlooWaterlooCanada
  6. 6.Université Grenoble AlpesGrenobleFrance
  7. 7.University of ManitobaWinnipegCanada
  8. 8.University of VictoriaVictoriaCanada
  9. 9.University of LethbridgeLethbridgeCanada

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