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Il 06/12/2011 23:49, David Gobbi ha scritto:
<blockquote
cite="mid:CANwS1=HVOdBPuh2gEMNjXs2rzdE6c96hSkzWApD1aeNHnaEvcQ@mail.gmail.com"
type="cite">
<div>The title of the paper advertises (states) that the method is
closed form (expressed as a set of equations that can be
directly evaluated to give the solution).</div>
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<div>Within the paper, one important step of the method is done
with a standard iterative (i.e. not closed-form) algorithm to
find the eigenvalues of a 4x4 matrix.</div>
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</div>
<div>So, the solution presented in the paper is not closed-form.
The paper states that a closed-form solution for the
eigenvalues of a 4x4 matrix exists, but it does not use the
closed-form solution. It uses an iterative solution instead.</div>
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</div>
<div>It wasn't until later (maybe 2002?) that someone finally
published a fully closed-form solution. But VTK uses Horn's
method, not the new method. People who are just using the
method (rather than implementing it) probably will not care one
way or the other... the two methods would give nearly identical
answers.</div>
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- David
<div><br>
<br>
<div class="gmail_quote">On Tue, Dec 6, 2011 at 3:17 PM, andon <span
dir="ltr"><<a moz-do-not-send="true"
href="mailto:antoniod987@gmail.com" target="_blank">antoniod987@gmail.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">I've not
understood what do you mean for " it isn't a closed form
solution as<br>
advertised." and "The complete closed-form solution was
developed later.<br>
</blockquote>
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</blockquote>
Wonderfull and perfect description, thank you very much. I'm using
the transfomr but i need also these "theorical" aspects because i'll
describe the workflow of my application also from a theorical point
of view.. Thank you very much again, your help has been very very
very usefull for me.<br>
Good night<br>
Antonio<br>
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