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Topic: An Argument for the Subroot Node
Replies: 28   Last Post: Mar 14, 2008 8:32 PM

 Messages: [ Previous | Next ]
 Tony Orlow Posts: 3,142 Registered: 8/23/06
Re: An Argument for the Subroot Node
Posted: Mar 11, 2008 10:21 AM

G. Frege wrote:
> On Tue, 11 Mar 2008 00:31:24 -0700, Virgil <Virgil@com.com> wrote:
>

>> If Tony wants to attach such an appendix to his trees, fine, but no one
>> else needs one [...].
>>

> Even worse. Such a structure (graph) is not a /tree/ any more (since a
> tree doe not have cycles _by definbition_).
>
>
> F.
>

If a normal tree can have a parent for every node except the root, then
this kind of tree can allow no cycles except at the subroot. You are
simply trading one exception for another, since you've eliminated the
root exception in the process. The effect is to provide a parent for
every node, and make the count of nodes up to level n equal to 2^n. So,
it's not "worse" that what you consider a tree. It's simply the result
of extrapolating upwards arithmetically to see what kind of parent the
root *could* have. And, it's got one alright. :)

T.

Date Subject Author
3/11/08 Tony Orlow
3/11/08 Virgil
3/11/08 G. Frege
3/11/08 Tony Orlow
3/11/08 Virgil
3/11/08 Tony Orlow
3/11/08 Virgil
3/11/08 G. Frege
3/11/08 J. Antonio Perez M.
3/11/08 G. Frege
3/11/08 G. Frege
3/11/08 Tony Orlow
3/11/08 briggs@encompasserve.org
3/14/08 Tony Orlow
3/14/08 David R Tribble
3/14/08 LudovicoVan
3/11/08 Tony Orlow
3/11/08 J. Antonio Perez M.
3/11/08 Tony Orlow
3/11/08 Tony Orlow
3/11/08 Tony Orlow
3/11/08 LudovicoVan
3/11/08 LudovicoVan
3/14/08 Tony Orlow
3/14/08 LudovicoVan
3/14/08 LudovicoVan
3/11/08 David R Tribble
3/11/08 LudovicoVan
3/11/08 LudovicoVan