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Re: transitive closure again

From: Mikito Harakiri <mikharakiri_nospaum_at_yahoo.com>
Date: 4 Nov 2005 15:10:41 -0800
Message-ID: <1131145841.221886.302860@z14g2000cwz.googlegroups.com>


paul c wrote:
> Here's one for the theorists (further to the thread from a month or two
> ago where I said some nonsense about obtaining the closure without
> recursion and which has been proved wrong many times and although I find
> the proofs hard to follow).
>
> Let me turn it around and ask a converse question:
>
> If we have a relation that is the closure (including trivial
> relationships if necessary), can we obtain what Mikito (if I recall),
> calls the adjacency list, using the RM algebra but without recursion?

Seems easy: for all pairs of nodes making an edge (x,y ) in the TC graph, select only those that aren't represented as (x,z) & (z,y). Received on Fri Nov 04 2005 - 17:10:41 CST

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