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From: roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson)
Newsgroups: comp.soft-sys.matlab
Subject: Re: Need algorithm help: molecule length from an image
Date: Sun, 11 May 2008 23:12:36 +0000 (UTC)
Organization: National Research Council Canada - Conseil national de rechereches Canada
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In article <g07jfi$afk$1@fred.mathworks.com>,
Roger Stafford <ellieandrogerxyzzy@mindspring.com.invalid> wrote:

>  Note to ImageAnalyst: In my opinion the length of the shape's perimeter 
>(presumably divided by 2) is not a reliable measure of what Adrian is seeking 
>as the over-all length of a molecule.  Its outline is likely to be a somewhat 
>jagged affair as is characteristic of long-chain molecules with differing kinds 
>of structures and would tend to give too large and inconsistent a value.

Hmmm, that triggers the throught that the molecule may have significant
3 dimensional components; unless we have at least two views of it
in different planes, we would not be able to tell whether the molecule
just happens to be shorter in the direction of view, but long into
or out of the direction of view.
-- 
  "The quirks and arbitrariness we observe force us to the
  conclusion that ours is not the only universe." -- Walter Kistler