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Bounds for rectilinear crossing numbers

✍ Scribed by Daniel Bienstock; Nathaniel Dean


Publisher
John Wiley and Sons
Year
1993
Tongue
English
Weight
780 KB
Volume
17
Category
Article
ISSN
0364-9024

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✦ Synopsis


Abstract

A rectilinear drawing of a graph is one where each edge is drawn as a straight‐line segment, and the rectilinear crossing number of a graph is the minimum number of crossings over all rectilinear drawings. We describe, for every integer k β‰₯ 4, a class of graphs of crossing number k, but unbounded rectilinear crossing number. This is best possible since the rectilinear crossing number is equal to the crossing number whenever the latter is at most 3. Further, if we consider drawings where each edge is drawn as a polygonal line segment with at most one break point, then the resulting crossing number is at most quadratic in the regular crossing number. Β© 1993 John Wiley & Sons, Inc.


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