I'm doing group analysis using a slightly modified version of AA-mod v4.0b Matlab script to do a t-test of contrasts in SPM8. I'm getting the following error:
***** error: *******
SPM8: spm_spm (v4191)
Initialising parameters : ...done
Output images : ...initialised
Plane 46/46 , block 1/1 : ...done
Spatial non-sphericity (over scans) : ...writing resels/voxel image??? NaN's cannot be converted to logicals.
Error in ==> spm_est_smoothness at 260
FWHM(~FWHM) = 1;
Error in ==> spm_spm at 928
[FWHM,VRpv,R] = spm_est_smoothness(VResI,VM,[nScan erdf]);
***** end error *******
With error debugging on, I see that V, Ix, Iy, Iz are non-empty, but FWHM = [NaN NaN NaN], and in fact d,dx,dy,dz are filled with NaN's when returned by the spm_sample_vol call in spm_est_smoothness:
[d,dx,dy,dz] = spm_sample_vol(V(i),Ix,Iy,Iz,1);
Thanks in advance for any pointers!