Convex node set
From Egres Open
In a digraph D=(V,A) with disjoint node sets X and Y, we say that Y is reachable from X if there is a directed path in D whose first node is in X and last node is in Y. A subset [math]T\subseteq V[/math] is called convex if there is no node v in V-T so that T is reachable from {v} and {v} is reachable from T.
