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<font size="+2"><tt><br>
Dear ITK-users,<br>
<br>
I used the itk::matrix<double,3,3> class to compute the matrix
inverse (GetInverse()) for a 3x3 matrix and I got a warning followed by
an incorrect answer.<br>
<br>
I found the correct inverse in matlab and checked that the condition
number of the matrix was 1.<br>
<br>
So I am wondering why vnl would find this difficult. I also did not
understand the warnings very well. It would be great if someone shed
some light on this. Thank you so much.<br>
<br>
</tt></font><font size="+2"><tt>Best regards,<br>
Suyash.<br>
</tt></font><br>
<font size="+2"><tt><br>
matrix<br>
0.99925 0.0371382 -0.0109982<br>
-0.0373772 0.99905 -0.0223916<br>
0.0101562 0.0227859 0.999689<br>
<br>
<br>
warnings:<br>
InsightToolkit-2.2.0/Utilities/vxl/core/vnl/algo/vnl_svd.txx:
suspicious return value (2) from SVDC<br>
InsightToolkit-2.2.0/Utilities/vxl/core/vnl/algo/vnl_svd.txx: M is 3x3<br>
M = [ ...<br>
0.9992500000000 0.0371382000000 -0.0109982000000<br>
-0.0373772000000 0.9990500000000 -0.0223916000000<br>
0.0101562000000 0.0227859000000 0.9996890000000 ]<br>
<br>
<br>
</tt></font><font size="+2"><tt>matrix inverse using vnl in itk
(incorrect)<br>
-0.982557 -0.0644525 -0.174434<br>
-0.0677511 0.997618 0.0130162<br>
-0.17318 -0.0246073 0.984583<br>
<br>
<br>
</tt></font><font size="+2"><tt>matrix inverse in matlab (correct)<br>
0.9992 -0.0374 0.0102<br>
0.0371 0.9991 0.0228<br>
-0.0110 -0.0224 0.9997<br>
<br>
<br>
</tt></font>
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