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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hello,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am creating a new metric using CUDA implementation. So far
I found it is very difficult to get the derivative value from my
implementation. I’d like to know if there is an optimizer in ITK which is
derivative free. Or is there any other way to calculate the derivative value?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks a lot!<o:p></o:p></span></font></p>
<p class=section1 style='margin:0cm;margin-bottom:.0001pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p class=section1 style='margin:0cm;margin-bottom:.0001pt'><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>Huanxiang Lu</span></font><o:p></o:p></p>
<p class=section1 style='margin:0cm;margin-bottom:.0001pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'><o:p> </o:p></span></font></p>
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12.0pt'><o:p> </o:p></span></font></p>
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