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<DIV><FONT face=Arial size=2><SPAN
class=290542411-22092008>Folks.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=290542411-22092008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=290542411-22092008>The implementation
of the computation of derivative for VersorRigidTransform and
VersorRigid3DTransform are </SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=290542411-22092008>unstable for
</SPAN></FONT><FONT face=Arial size=2><SPAN class=290542411-22092008>rotations
of 180 degrees, and after looking into the code, I see that the divide-by-zero
may </SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=290542411-22092008>happen for a range
of versor values.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=290542411-22092008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=290542411-22092008>Can
someone check this out, and suggest corrections that may be
needed? </SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=290542411-22092008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=290542411-22092008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=290542411-22092008>Sohan</SPAN></FONT><FONT face=Arial size=2><SPAN
class=290542411-22092008> </SPAN></FONT></DIV></BODY></HTML>