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Re: What databases have taught me

From: Marshall <marshall.spight_at_gmail.com>
Date: 25 Jun 2006 17:34:20 -0700
Message-ID: <1151282060.420603.80620@b68g2000cwa.googlegroups.com>


Chris Smith wrote:
> [...]

Thanks for the very informative writeup.

Upon further (modest) analysis of the problem, it appears that finding regions from edges is a transitive closure problem, so there is, I will not say "difficulty" but perhaps "challenge." The rest is more or less trivial.

> - You don't need faces; just a (unordered) nodes and edges.

Are you sure?

Consider a square, with four points, top-left, top-right, bottom-left, bottom-right. Now add a fifth edge, from top-right to bottom-left.

If this edge goes through the interior of the square, that is a different set of regions than if it goes around the outside of the square.

Marshall Received on Sun Jun 25 2006 - 19:34:20 CDT

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