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arXiv · 1807.09483

A Greedy Heuristic for Crossing-Angle Maximization

Almut Demel·Dominik Dürrschnabel·Tamara Mchedlidze·Marcel Radermacher·Lasse Wulf
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Abstract

The crossing angle of a straight-line drawing $\Gamma$ of a graph $G=(V, E)$ is the smallest angle between two crossing edges in $\Gamma$. Deciding whether a graph $G$ has a straight-line drawing with a crossing angle of $90^\circ$ is $\mathcal NP$-hard. We propose a simple heuristic to compute a drawing with a large crossing angle. The heuristic greedily selects the best position for a single vertex in a random set of points. The algorithm is accompanied by a speed-up technique to compute the crossing angle of a straight-line drawing. We show the effectiveness of the heuristic in an extensive empirical evaluation. Our heuristic was clearly the winning algorithm (CoffeeVM) in the Graph Drawing Challenge 2017.

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Almut Demel, Dominik Dürrschnabel, Tamara Mchedlidze, Marcel Radermacher, Lasse Wulf. 2018-07-25. A Greedy Heuristic for Crossing-Angle Maximization. https://arxiv.org/abs/1807.09483

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