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From: ImageAnalyst <imageanalyst@mailinator.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Ranking points in the plane
Date: Thu, 4 Nov 2010 08:26:28 -0700 (PDT)
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It looks like these are (x,y,z) triplets.  It looks like x is constant
so that your points are in the y-z plane located at x=0.5.  So just do
this: "Follow Walter's suggestions" so that you get the vertices going
around in one direction, for example clockwise.  Then when you plot
the quad, you won't have any crossing ("diagonals") because you're
going around it in one direction (e.g. clockwise).