Hi Antonietta,
I?have a simple question about the interpretation of the realignment
parameters saved in rp_*.txt file when using the "Realign:Estimate &
Reslice" SPM function .
the rp-file should contain 6 colums and a row for each scan, which you have realigned.
The first three coloums are the x, y, z- translation, the other three are the rotations pitch, roll, and yaw.
I?m not sure about how should I read them in order to build the
related transformation matrix.
You should also check the spm_realign file (or type 'help spm_realign' in the MATLAB window).
The rp_*.txt file contains just a list of 12 numbers (e.g.
1.0103030e-014 1.2101431e-014 0.0000000e+000 0.0000000e+000
-2.1734570e-051 -1.5616324e-016 -1.5004945e+001 2.6234784e+001
2.6747571e+001 -1.1082900e-001 -3.3493469e-002 -4.0569124e-002) but
However, I would be more worried about the numbers you wrote down in your e-mail, since they are in the range between e-051 to e+001. In my experience, that's a little bit unusual range ...
Karsten
--
-------------------------------------------------------------
Karsten Specht, PhD
Department of Biological and Medical Psychology
& National Competence Centre for functional MRI
University of Bergen
Jonas Lies vei 91
5009 Bergen
Norway
Tel.: +47-555-86279
Fax: +47-555-89872
