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arXiv · 1808.09931

Level Planarity: Transitivity vs. Even Crossings

Guido Brückner·Ignaz Rutter·Peter Stumpf
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Abstract

Recently, Fulek et al. have presented Hanani-Tutte results for (radial) level planarity, i.e., a graph is (radial) level planar if it admits a (radial) level drawing where any two (independent) edges cross an even number of times. We show that the 2-Sat formulation of level planarity testing due to Randerath et al. is equivalent to the strong Hanani-Tutte theorem for level planarity. Further, we show that this relationship carries over to radial level planarity, which yields a novel polynomial-time algorithm for testing radial level planarity.

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Guido Brückner, Ignaz Rutter, Peter Stumpf. 2018-08-29. Level Planarity: Transitivity vs. Even Crossings. https://arxiv.org/abs/1808.09931

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