Path: utzoo!utgpu!water!watmath!watdragon!lion!jtfox
From: jtfox@lion.waterloo.edu (Todd Fox)
Newsgroups: comp.graphics
Subject: Re: smallest contining circle
Keywords: computational geometry, circle, convex hull
Message-ID: <6431@watdragon.waterloo.edu>
Date: 16 Apr 88 21:24:02 GMT
References: <825@wucs2.UUCP>
Sender: daemon@watdragon.waterloo.edu
Reply-To: jtfox@lion.waterloo.edu (Todd Fox)
Organization: U. of Waterloo, Ontario
Lines: 24

In article <825@wucs2.UUCP> posdamer@wucs2.UUCP (Jeff Posdamer) writes:
>Here we go again. PLEASE DON'T GUESS IF YOU DON'T KNOW!!!!
>
>The solution has the following steps:
>	A. Compute the convex hull of the point set 
>	B. Compute maximum distance between points on convex hull polygon
>	using   a hodograph algorithm
>	C. Use maximum distance line segment as diameter of circle.

My roomie says this ain't so. What if you have three points as the
vertices of an equilateral triangle. The convex hull IS the triangle. 
If the sides of the triangle are  of length 1, the circle must 
have diameter 2/sqrt(3) > 1 (and MAX DIST. = 1).

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Alan Myrvold     ajmyrvold@violet.waterloo.edu
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--
Todd Fox  JTFOX@LION.WATERLOO.EDU
Ob ich dich liebe? Naturlich liebe ich dich! Wir sind doch schon
wieder im Bett, nicht wahr?