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Abstract
To untangle a geometric graph means to move some of the vertices so that the resulting geometric graph has no crossings. Pach and Tardos (Discrete Comput. Geom. 28(4): 585–592,2002) asked if everyn-vertex geometric planar graph can be untangled while keeping at leastnε vertices fixed. We answer this question in the affirmative withε=1/4. The previous best known bound was\(\Omega(\sqrt{\log n/\log\log n})\). We also consider untangling geometric trees. It is known that everyn-vertex geometric tree can be untangled while keeping at least\(\Omega(\sqrt{n})\) vertices fixed, while the best upper bound was\(\mathcal{O}((n\log n)^{2/3})\). We answer a question of Spillner and Wolff (http://arxiv.org/abs/0709.0170) by closing this gap for untangling trees. In particular, we show that for infinitely many values of n, there is ann-vertex geometric tree that cannot be untangled while keeping more than\(3(\sqrt{n}-1)\) vertices fixed.
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References
Abellanas, M., Hurtado, F., Ramos, P.: Tolerancia de arreglos de segmentos. In: Proc. VI Encuentros de Geometría Computacional, pp. 77–84 (1995)
Cibulka, J.: Untangling polygons and graphs. In: Topological and Geometric Graph Theory. Electronic Notes in Discrete Mathematics, vol. 31, pp. 207–211 (2008)
de Fraysseix, H., Pach, J., Pollac, R.: How to draw a planar graph on a grid. Combinatorica10(1), 41–51 (1990)
Dilworth, R.P.: A decomposition theorem for partially ordered sets. Ann. Math.51(2), 161–166 (1950)
Erdős, P., Szekeres, G.: A combinatorial problem in geometry. Compos. Math.2, 464–470 (1935)
Fáry, I.: On straight line representation of planar graphs. Acta Univ. Szeged. Sect. Sci. Math.11, 229–233 (1948)
Goaoc, X., Kratochvil, J., Okamoto, Y., Shin, C.-S., Wolff, A.: Moving vertices to make drawings plane. In: Proc. 15th International Symp. on Graph Drawing (GD’07). Lecture Notes in Computer Science, vol. 4875, pp. 101–112. Springer, Berlin (2008). Also inhttp://arxiv.org/abs/0706.1002
Hong, S.-H., Nagamochi, H.: Convex drawings of graphs with non-convex boundary constraints. Discrete Appl. Math.156(12), 2368–2380 (2008)
Kang, M., Pikhurko, O., Ravsky, A., Schacht, M., Verbitsky, O.: Obfuscated drawings of planar graphs (2008).http://arxiv.org/abs/0803.0858
Kang, M., Schacht, M., Verbitsky, O.: How much work does it take to straighten a plane graph out? (2007).http://arxiv.org/abs/0707.3373
Pach, J., Tardos, G.: Untangling a polygon. Discrete Comput. Geom.28(4), 585–592 (2002)
Ramos, P.: Tolerancia de estructuras geométricas y combinatorias. Ph.D. thesis, Universidad Politécnica de Madrid, Madrid, Spain (1995)
Ravsky, A., Verbitsky, O.: On collinear sets in straight line drawings (2008).http://arxiv.org/abs/0806.0253
Spillner, A., Wolff, A.: Untangling a planar graph. In: Proc. 34th Internat. Conf. on Current Trends in Theory and Practice of Computer Science (SOFSEM’08). Lecture Notes in Computer Science, vol. 4910, pp. 473–484. Springer, Berlin (2008). Also inhttp://arxiv.org/abs/0709.0170
Verbitsky, O.: On the obfuscation complexity of planar graphs. Theor. Comput. Sci.396(1–3), 294–300 (2008)
Wagner, K.: Über eine Eigenschaft der ebene Komplexe. Math. Ann.114, 570–590 (1937)
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Authors and Affiliations
School of Computer Science, Carleton University, Ottawa, Canada
Prosenjit Bose & Pat Morin
Department of Mathematics and Statistics, McGill University, Montreal, Canada
Vida Dujmović
Departament de Matemàtica Aplicada II, Universitat Politècnica de Catalunya, Barcelona, Spain
Ferran Hurtado
FNRS, Département d’Informatique, Université Libre de Bruxelles, Brussels, Belgium
Stefan Langerman
Department of Mathematics and Statistics, The University of Melbourne, Melbourne, Australia
David R. Wood
- Prosenjit Bose
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- Vida Dujmović
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- Stefan Langerman
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Correspondence toProsenjit Bose.
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Research of P. Bose and P. Morin was partially supported by NSERC.
Research of V. Dujmović was partially supported by CRM and NSERC.
Research of F. Hurtado was supported by projects MEC MTM2006-01267 and DURSI 2005SGR00692.
Research of D.R. Wood was supported by a QEII Research Fellowship. Research initiated at the Universitat Politècnica de Catalunya, where supported by the Marie Curie Fellowship MEIF-CT-2006-023865, and by projects MEC MTM2006-01267 and DURSI 2005SGR00692.
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Bose, P., Dujmović, V., Hurtado, F.et al. A Polynomial Bound for Untangling Geometric Planar Graphs.Discrete Comput Geom42, 570–585 (2009). https://doi.org/10.1007/s00454-008-9125-3
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