<div dir="ltr">Dear Matt, <div><br></div><div>thank you very much for the quick reply. </div><div><br></div><div>If I've got it correctly the scale parameters tell the optimizer in which order of magnitude should move in every direction, while the weights are just used in order to privilege convergence according to a certain number of sub parameters. </div><div><br></div><div>I would rather ask you another question about the scales. In the ITK software guide "3.18.2 General heuristics for parameters" it is suggested to scale the translation parameters of the optimizer in he following way</div><div><span class="" style="white-space:pre"> </span>// optimizerScales[9] = 1.0 / (10 * movingSpacing[0] * movingSize[0])</div><div><span class="" style="white-space:pre"> </span>// optimizerScales[10] = 1.0 / (10 * movingSpacing[1] * movingSize[1])</div><div><span class="" style="white-space:pre"> </span>// optimizerScales[11] = 1.0 / (10 * movingSpacing[2] * movingSize[2])</div><div><br></div><div>Is this what is done by the SetScaleEstimator() method?</div><div><br></div><div>Best,</div><div><br></div><div>Luigi</div><div><br></div><div> </div></div><div class="gmail_extra"><br><div class="gmail_quote">2015-11-09 17:18 GMT+01:00 Matt McCormick <span dir="ltr"><<a href="mailto:matt.mccormick@kitware.com" target="_blank">matt.mccormick@kitware.com</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi Luigi,<br>
<br>
The SetScales and SetWeights have different purposes. SetScales is<br>
used to account for different parameters having a different impact on<br>
motion -- for example, translation versus rotation parameters.<br>
SetWeights can be used to keep one parameter constant, etc. A more<br>
detailed description can be found in the class documentation here:<br>
<br>
<a href="http://www.itk.org/Insight/Doxygen/html/classitk_1_1ObjectToObjectOptimizerBaseTemplate.html" rel="noreferrer" target="_blank">http://www.itk.org/Insight/Doxygen/html/classitk_1_1ObjectToObjectOptimizerBaseTemplate.html</a><br>
<br>
HTH,<br>
Matt<br>
<div><div class="h5"><br>
On Mon, Nov 9, 2015 at 10:16 AM, Luigi Riba <<a href="mailto:ribaluigi@gmail.com">ribaluigi@gmail.com</a>> wrote:<br>
> Dear all,<br>
><br>
> I'm working on ITK 4 and, for the moment, I have always payed attention only<br>
> to the SetScales method for the optimizer.<br>
><br>
> Out of curiosity, what is the role of the SetWeights method? What are the<br>
> differences between SetWeights and SetScales? Shoud this two methods be used<br>
> in conjunction?<br>
><br>
> Thanks in advance for the help.<br>
><br>
> Best,<br>
> Luigi<br>
><br>
</div></div>> _______________________________________________<br>
> Community mailing list<br>
> <a href="mailto:Community@itk.org">Community@itk.org</a><br>
> <a href="http://public.kitware.com/mailman/listinfo/community" rel="noreferrer" target="_blank">http://public.kitware.com/mailman/listinfo/community</a><br>
><br>
</blockquote></div><br></div>