Rooted Kernels and Labeled Combinatorial Pyramids
نویسندگان
چکیده
An irregular pyramid consists of a stack of successively reduced graphs. Each smaller graph is deduced from the preceding one using contraction or removal kernels. A contraction (resp. removal) kernel defines a forest of the initial (resp. dual ) graph, each tree of this forest being reduced to a single vertex (resp. dual vertex) in the reduced graph. A combinatorial map encodes a planar graph thanks to two permutations encoding the edges and their orientation around the vertices. We present in this article a new definition of contraction and removal kernels which allows to encode the different values attached to a given vertex, dual vertex or edge along the pyramid.
منابع مشابه
Contraction kernels and combinatorial maps
Graph pyramids are made of a stack of successively reduced graphs embedded in the plane. Such pyramids overcome the main limitations of their regular ancestors. The graphs used in the pyramid may be region adjacency graphs, dual graphs or combinatorial maps. Compared to usual graph data structures, combinatorial maps offer an explicit encoding of the orientation of edges around vertices. Each c...
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