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I'm looking for the name of a shape that is like a capsule, but where each circle can have different radii. The shape could be described using two circles (two centers and two radii). Something like this (this is a 2D shape, not a lame attempt at 3D): alt text

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2 Answers 2

up vote 9 down vote accepted

You can just say it is the convex hull of two circles.

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Yeah that's a simpler definition. A name would be cool though, as I'd like to use it as the name of a class in a program and ConvexHullOfTwoCircles is not too catchy. –  Trillian Jul 31 '10 at 1:29
What about Pear? –  Qiaochu Yuan Jul 31 '10 at 2:13
It looks like a pulley and belt system, so how about PulleyBeltShape? –  user115 Jul 31 '10 at 4:45
I'm accepting this because the shape doesn't seem to have a name and this is a helpful definition. –  Trillian Jul 31 '10 at 12:56
@Qiaochu Haha, Pear's not bad but, if you're into fruits, Avocado seems more fit! –  Trillian Jul 31 '10 at 13:05

Here is an article at Mathworld on Circle-Circle Tangents. Perhaps "CirclesWithTangents"?

Circle-Circle Tangents

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Hmm... not too sure for the name, but thanks for that article, it should be helpful with what I intend to do with this shape. –  Trillian Jul 31 '10 at 12:55
@Dennis Williamson Circle with Direct tangents –  Narasimham Sep 5 '14 at 23:42

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