ugur bozkaya
Thu. 23 Feb.06, 10:10
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L1,L2,L3 ae the eigenvalues of the corresponding tensor.
LM=(L1+L2+L3)/3
Numerator = 3*[(L1-LM)^2 + (L2-LM)^2 + (L3-LM)^2]
Denominator = 2*[L1^2 + L2^2 + L3^2]
FA = sqrt(Numerator / Denominator )
Another definition is as follows:
Numerator = [(L1-L2)^2 + (L2-L3)^2 + (L3-L1)^2]
Denominator = 2*[L1^2 + L2^2 + L3^2]
FA = sqrt(Numerator / Denominator )
Hope this helps.
ref: http://ajp.psychiatryonline.org/cgi/content/full/161/3/573
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