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Degree-preserving trees

✍ Scribed by Broersma, Hajo; Koppius, Otto; Tuinstra, Hilde; Huck, Andreas; Kloks, Ton; Kratsch, Dieter; M�ller, Haiko


Publisher
John Wiley and Sons
Year
2000
Tongue
English
Weight
186 KB
Volume
35
Category
Article
ISSN
0028-3045

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✦ Synopsis


We consider the degree-preserving spanning tree (DPST) problem: Given a connected graph G G G, find a spanning tree T T T of G G G such that as many vertices of T T T as possible have the same degree in T T T as in G G G. This problem is a graph-theoretical translation of a problem arising in the system-theoretical context of identifiability in networks, a concept which has applications in, for example, water distribution networks and electrical networks. We show that the DPST problem is NP-complete, even when restricted to split graphs or bipartite planar graphs, but that it can be solved in polynomial time for graphs with a bounded asteroidal number and for graphs with a bounded treewidth. For the class of interval graphs, we give a linear time algorithm. For the class of cocomparability graphs, we give an O O O(n n n 4 ) algorithm. Furthermore, we present linear time approximation algorithms for planar graphs of a worst-case performance ratio of 1for every > 0.


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