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MathGroup Archive 2000

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Point inside a plygon (again)

  • To: mathgroup at smc.vnet.net
  • Subject: [mg25402] Point inside a plygon (again)
  • From: Adriano Pascoletti <pascolet at dimi.uniud.it>
  • Date: Fri, 29 Sep 2000 01:06:42 -0400 (EDT)
  • Sender: owner-wri-mathgroup at wolfram.com

Dear MathGroup,

some days ago ([mg25323] Re: [mg25239] Point inside a polygon?) I suggested
Adriano Moreira
>See the constructive proof of Theorem 2.1, Sect. 2.2 of
>F.P.Preparata, M.I.Shamos: Computational Geometry, Springer 1985

Here is an implementation (with some comments) whose accuracy depends on
the accuracy of two tests
i. x==y (x,y reals)
ii. Det[m]>0 (m 3 by 3).


Adriano Pascoletti



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----------------------------------------
Adriano Pascoletti
Dipartimento di Matematica e Informatica
Universita' di Udine
Via delle Scienze 206
I-33100 UDINE
Italy

Tel. +39-0432-558441
Fax. +39-0432-558499

http://www.dimi.uniud.it/~pascolet




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