Re: dual graph

From: Chris Smith <>
Date: Mon, 26 Jun 2006 08:55:02 -0600
Message-ID: <>

David Cressey <> wrote:
> Thanks to everybody for clearing up the matter of "planar".
> Now, I'm interested in a a subset of the planar graphs.
> It's the graphs that don't divide the space into more than one region.
> It seems to me that it's appropriate to call such graphs "hierarchical
> graphs", or simply "hierarchies". But I'm not sure. Can anyone clear this
> up?

Well, such a graph has no cycles, so it is a forest. If it's connected, then it's a tree. I don't know where Dmitry got "ordered". Any graph (planar or not, cycles or not, doesn't matter) may be made into an ordered graph simply by defining an order for its nodes.

Chris Smith - Lead Software Developer / Technical Trainer
MindIQ Corporation
Received on Mon Jun 26 2006 - 16:55:02 CEST

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