On point-halfspace graphs
✍ Scribed by Edward R. Scheinerman; Ann N. Trenk; Daniel Ullman
- Book ID
- 102893239
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 744 KB
- Volume
- 20
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The following definition is motivated by the study of circle orders and their connections to graphs. A graphs G is called a point‐halfspace graph (in R^k^) provided one can assign to each vertex v ϵ (G) a point p~v~ R^k^ and to each edge e ϵ E(G) a closed halfspace H~e~ ϵ R^k^ so that v is incident with e if and only if p~v~ ϵ H~e~. Let H^k^ denote the set of point‐halfspace graphs (in R^k^).
We give complete forbidden subgraph and structural characterizations of the classes H^k^ for every k. Surprisingly, these classes are closed under taking minors and we give forbidden minor characterizations as well. © 1996 John Wiley & Sons, Inc.
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