Partitioned Probe Comparability Graphs

Given a class of graphs G, a graphG is a probe graph of G if its vertices can be partitioned into a set of probes and an independent set of nonprobes such that G can be embedded into a graph of G by adding edges between certain nonprobes. If the partition of the vertices is part of the input, we call G a partitioned probe graph of G. In this paper we show that there exists a polynomial-time algorithm for the recognition of partitioned probe graphs of comparability graphs. This immediately leads to a polynomial-time algorithm for the recognition of partitioned probe graphs of cocomparability graphs. We then show that a partitioned graph G is a partitioned probe permutation graph if and only if G is at the same time a partitioned probe graph of comparability and cocomparability graphs. c © 2008 Elsevier B.V. All rights reserved.