In this paper we show that any maximal planar graph with m triangles except the unbounded face can be transformed into a straight-line embedding in which at least Wmร3X triangles are acute triangles. Moreover, we show that any maximal outerplanar graph can be transformed into a straight-line embeddi
On a straight-line embedding problem of graphs
โ Scribed by Shin-ichi Tokunaga
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 372 KB
- Volume
- 150
- Category
- Article
- ISSN
- 0012-365X
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โฆ Synopsis
Let G be a planar graph with n vertices, v be a specified vertex of G, and P be a set of n points in the Euclidian plane ~2 in general position. A straight-line embeddin9 of G onto P is an embedding of G onto R 2 whose images of vertices are distinct points in P and whose images of edges are (straight) line segments. In this paper, we classify into five classes those pairs of G and v such that for any P and any p E P, G has a straight-line embedding onto P which maps v to p. We then show that all graphs in three of the classes indeed have such an embedding. This result gives a solution to a generalized version of the rooted-tree embedding problem raised by M. Perles.
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