> Date: Mon, 01 Jul 2002 16:21:26 -0700 > From: Rick Klement <[EMAIL PROTECTED]> > > Phil Carmody wrote: > > --- Rick Klement <[EMAIL PROTECTED]> wrote: > > > "Nodes that are isolated nodes (the name appears twice on the > > > same line), can also be in a relationship to other nodes." > > > > But does that make them cycles or not? > > Having the same name appears twice on the same line does NOT make a cycle.
I think the real problem is the term isolated node. An true isolated node would be one that has no relation with other nodes in the input partial order --- and it's true that the only way to input such a node is to give its relation to itself. However, by the definition of partial order (reflexive, antisymmetric, transitive), all nodes have such a relation --- which does not create a cycle --- but it can be omitted (inferred) if the node is mentioned in other relations. The question then is if it must be omitted in that case: and you answer no. But --- if the input can contain reflexive relations for nodes that aren't really isolated, perhaps you should use a term that reflects that. Lars Mathiesen (U of Copenhagen CS Dep) <[EMAIL PROTECTED]> (Humour NOT marked)
