in coregistration code( spm_coreg and spm_powell)
do you know that what is the meaning of
xi = diag(sc*20); where sc is defined as follows:
sc=[0.02 0.02 0.02 0.001 0.001 0.001 0.01 0.01 0.01 0.001 0.001 0.001]';
in powell optimization xi should show the direction of search, as
default it is identity matrix( eye(6) in this case), but in spm code, it
is taken multiple of tolerance with 20. Have you got any ideas about
this initialization? When I enter manually, identity in replace to xi,
co-registration result is not promising.
thanks in any advance reply.
This message has been checked for viruses but the contents of an attachment
may still contain software viruses, which could damage your computer system:
you are advised to perform your own checks. Email communications with the
University of Nottingham may be monitored as permitted by UK legislation.