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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: Fri, 9 May 2008 19:35:02 +0000 (UTC)
Organization: National Research Council Canada - Conseil national de rechereches Canada
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In article <g023qb$j0m$1@fred.mathworks.com>, Adrian  <ajr@med.unc.edu> wrote:

>My name is Adrian Randall and I work in an Electron
>Microscopy lab. I am trying to determine the lengths of
>molecules from images using MATLAB.

I had a glance at the image, and the first question in my mind
was whether you want the length as folded (e.g., the length
of an appropriate oriented bounded box), or if you want the
length as if were unfolded (length of the perimeter) ? If as if
unfolded, then how should the loop at one end be treated, as
a circle whose diameter is to be taken, or the circumference
(af if the loop were stretched out to its maximum length) ?
-- 
  "Man's life is but a jest,
   A dream, a shadow, bubble, air, a vapor at the best."
                                         -- George Walter Thornbury