Re: A small practical mathematical riddle.

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Article #2833

#2833

From: Virgil
Date: Mon, 14 Jul 1997 00:00

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In article <EDAyEJ.5Hz@discus.technion.ac.il>,
s2845543@techst02.technion.ac.il (Raz Uri ) wrote:

> I will pose here a simple practical question
> ( which has a very nice answer).
> Given a simple poligon (doesn't cut itself) which is represnted
> by its corners coordinates (pinot) Xi,Yi , so (Xi Yi) (Xi+1 Yi+1)
> is an edge of the poligon, calculate the area.

Area  is half the absolute value of the sum of the determinants d(i,i+1)

where d(i,i+1) = || (X(i+1) - X(1))  (Y(i+1) - Y(i)) ||
                 || (x(i)   - X(1))  (Y(i)   - Y(i)) ||

-- 
V. Hancher
xvmhjr@xfrii.com
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<33B50F9C.6A78B22E@shani.net> <ED3AyK.4Mo@discus.technion.ac.il> <33C88693.D4@tmx100.elex.co.il> <01bc8f64$b2120c00$0a745ac2@liberpolly> <EDAxAz.43E@discus.technion.ac.il> <EDAyEJ.5Hz@discus.technion.ac.il>

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From: xvmhjr@xfrii.com (Virgil)
Subject: Re: A small practical mathematical riddle.
Date: 1997/07/14
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References: <33B50F9C.6A78B22E@shani.net> <ED3AyK.4Mo@discus.technion.ac.il> <33C88693.D4@tmx100.elex.co.il> <01bc8f64$b2120c00$0a745ac2@liberpolly> <EDAxAz.43E@discus.technion.ac.il> <EDAyEJ.5Hz@discus.technion.ac.il>
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