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<div>Hi <SPAN contentEditable=false style="DISPLAY: inline-block"></SPAN>Karthik,</div>
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<div>Thanks a lot.</div>
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<div>The 6 gradient images I meant were actually the Dxx, Dyy, Dzz, Dxy, Dxz, Dyz from D matrix.</div>
<div>I just don't know how itk::DiffusionTensor3D manage to store them and I cannot find the documentation that discribe it explicitly. Now I found it in DiffusionTensor3D .h. </div>
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<div></FONT><FONT color=#008000 size=2>// Note that the indices are related to the fact </div>
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<div></FONT><FONT color=#008000 size=2>// that we store only the upper-right triangle of</div>
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<div></FONT><FONT color=#008000 size=2>// the matrix. Like</div>
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<div></FONT><FONT color=#008000 size=2>// </div>
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<div></FONT><FONT color=#008000 size=2>// | 0 1 2 |</div>
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<div></FONT><FONT color=#008000 size=2>// | X 3 4 |</div>
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<div></FONT><FONT color=#008000 size=2>// | X X 5 |</div>
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<div></FONT><FONT color=#008000 size=2>// </div>
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<div></FONT><FONT color=#008000 size=2>// The trace is therefore the sum of the components</div>
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<div></FONT><FONT color=#008000 size=2>// M[0], M[3] and M[5].</FONT></div>
<div><FONT color=#008000 size=2></FONT> </div>
<div><FONT color=#008000>Cheers</FONT></div>
<div><FONT color=#008000 size=2></FONT> </div>
<div><FONT color=#008000 size=2>Best</FONT></div>
<div><FONT color=#008000 size=2>John</div>
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