Does anyone know the physical meaning of the "transform matrix" and the "quasinewton matrix" outputted during "EM Registration" of auto-recon2? For some odd reason, both of them are identity matrices (one's along the diagonal). I am almost certain that should not be the case.

Here is some context:

***********************************************
Computing MAP estimate using 1658 samples...
***********************************************

dt = 5.00e-06, momentum=0.80, tol=1.00e-05

l_intensity = 1.0000

Aligning input volume to GCA...

Transform matrix
 1.00000 0.00000 0.00000 0.00000;
 0.00000 1.00000 0.00000 0.00000;
 0.00000 0.00000 1.00000 0.00000;
 0.00000 0.00000 0.00000 1.00000;

nsamples 1658
Quasinewton: input matrix

 1.00000 0.00000 0.00000 0.00000;
 0.00000 1.00000 0.00000 0.00000;
 0.00000 0.00000 1.00000 0.00000;
 0.00000 0.00000 0.00000 1.00000;

 THE SEARCH DIRECTION IS NOT A DESCENT DIRECTION
 IFLAG= -1 LINE SEARCH FAILED. SEE DOCUMENTATION OF ROUTINE MCSRCH ERROR RETURN
 OF LINE SEARCH: INFO= 0 POSSIBLE CAUSES: FUNCTION OR GRADIENT ARE INCORRECT OR
INCORRECT TOLERANCESoutof QuasiNewtonEMA: 005: -log(p) = -0.0 tol 0.000010

Resulting transform:

 1.000 0.000 0.000 0.000;
 0.000 1.000 0.000 0.000;
 0.000 0.000 1.000 0.000;
 0.000 0.000 0.000 1.000;

pass 1, spacing 8: log(p) = -4.8 (old=-5.1)

transform before final EM align:

 1.000 0.000 0.000 0.000;
 0.000 1.000 0.000 0.000;
 0.000 0.000 1.000 0.000;
 0.000 0.000 0.000 1.000;

Thank you and happy holidays!

- Mark