Courcelle's theorem and the logic of graphs
- Crossing minimization for 1-page and 2-page drawings of graphs
with bounded treewidth.
M. J. Bannister and D. Eppstein.
arXiv:1408.6321.
22nd Int. Symp. Graph Drawing, Würzburg, Germany, 2014.
Springer, Lecture Notes in Comp. Sci. 8871, 2014, pp. 210–221.
J. Graph Algorithms & Applications 22 (4): 577–606, 2018.We show how to express in monadic second-order logic the problems of drawing a graph with a fixed number of crossings on a one or two page book layout. By applying Courcelle's theorem, we obtain fixed-parameter tractable algorithms for these problems, parameterized by treewidth.
- Rooted cycle bases.
D. Eppstein, J. M. McCarthy, and B. E. Parrish.
arXiv:1504.04931.
14th Algorithms and Data Structures Symp. (WADS 2015), Victoria, BC.
Springer, Lecture Notes in Comp. Sci. 9214 (2015), pp. 339–350.
J. Graph Algorithms & Applications 21 (4): 663–686, 2017.We consider the problem of finding a cycle basis for a graph in which all basis cycles contain a specified edge. We characterize the graphs having such a basis in terms of their vertex connectivity, we show that the minimum weight cycle basis with this constraint can be found in polynomial time and is weakly fundamental, and we show that finding a fundamental cycle basis with this constraint is NP-hard but fixed-parameter tractable.
(Slides)
- On the planar split thickness of graphs.
D. Eppstein, P. Kindermann, S. G. Kobourov, G. Liotta, A. Lubiw, A. Maignan, D. Mondal, H. Vosoughpour, S. Whitesides, and S. Wismath.
arXiv:1512.04839.
Proc. 12th Latin American Theoretical Informatics Symposium (LATIN 2016), Ensenada, Mexico.
Springer, Lecture Notes in Comp. Sci. 9644 (2016), pp. 403–415.
Algorithmica 80 (3): 977–994 (special issue for LATIN), 2018.We study the problem of splitting the vertices of a given graph into a bounded number of sub-vertices (with each edge attaching to one of the sub-vertices) in order to make the resulting graph planar. It is NP-complete, but can be approximated to within a constant factor, and is fixed-parameter tractable in the treewidth.
(Slides)
- K-best solutions of MSO problems on tree-decomposable graphs.
D. Eppstein and D. Kurz.
arXiv:1703.02784.
Proc. 12th International Symposium on Parameterized and Exact Computation (IPEC 2017), Vienna, Austria, 2017.
Leibniz International Proceedings in Informatics (LIPIcs) 89, pp. 16.1–16.13We show that, on graphs of bounded treewidth, for any optimization problem definable in monadic second-order logic, we can find the k best solutions in logarithmic time per solution.
- Subexponential-time and FPT algorithms for embedded flat clustered
planarity.
G. Da Lozzo, D. Eppstein, M. T. Goodrich, and S. Gupta.
arXiv:1803.05465
Proc. 44th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2018), Lübbenau, Germany.
Springer, Lecture Notes in Comp. Sci. 11159 (2018), pp. 111–124.Clustered planarity is the problem of simultaneously drawing a planar graph and a clustering of its vertices (as Jordan curves surrounding the cluster) with no unnecessary crossings between edges or cluster boundaries; it remains unknown whether it can be solved in polynomial time. We provide parameterized and subexponential exact algorithms for the case where the planar embedding is fixed and the clusters form a partition of the vertices.
- Parameterized leaf power recognition via embedding into graph products.
D. Eppstein and E. Havvaei.
arXiv:1810.02452.
Proc. 13th International Symposium on Parameterized and Exact Computation (IPEC 2018), Helsinki, Finland, 2018.
Leibniz International Proceedings in Informatics (LIPIcs) 115, 2018, pp. 16:1–16:14.
Algorithmica 82 (8): 2337–2359, 2020 (special issue for IPEC 2018).A leaf power graph is the graph formed from the leaves of a tree by making two leaves adjacent when their tree distance is at most k. We show that recognizing these graphs is fixed-parameter tractable in a combination of two parameters: k and the degeneracy of the graph.
(James Nastos has pointed out a minor error in our statement of known prior results: the figure depicting chordal graphs that are not 4-leaf powers is labeled as a complete set of forbidden subgraphs, but it is only the complete set among graphs without true twin vertices.)
- Homotopy height, grid-minor height and graph-drawing height.
T. Biedl, E. Chambers, D. Eppstein, A. de Mesmay, and T. Ophelders.
arXiv:1908.05706.
Proc. 27th Int. Symp. Graph Drawing, Prague, Czech Republic, 2019.
Springer, Lecture Notes in Comp. Sci. 11904 (2019), pp. 468–481.
We lower bound the height of a drawing of a planar graph in an integer grid by a topological invariant, the homotopy height, and show that this invariant is equal to the smallest height of a grid graph in which the given graph is a minor.
- Tracking paths in planar graphs.
D. Eppstein, M. T. Goodrich, P. Matias, and J. A. Liu.
arXiv:1908.05445.
Proc. 30th International Symposium on Algorithms and Computation (ISAAC 2019), Shanghai, China, 2019.
Leibniz International Proceedings in Informatics (LIPIcs) 149, 2019, pp. 54:1–54:17.A tracking set for a given graph, with designated start and destination vertices, is a set of vertices such that any path from start to destination is determined by the subsequence of its vertices that belong to the tracking set. We show that finding the smallest tracking set is NP-hard but has a constant factor approximation, and can be solved exactly in fixed-parameter-tractable time for graphs of bounded width.