Hi, List experts,

I had problems during the ROI combination, but I do not know how to understand the error alarms below. Is that I have problems with the ROIs themselves or anything else?

Thanks so much,
Juan

[S01@NY_Net] $ 3dcalc -a MPFC.nii -b VMPFC.nii -expr '(a+b)' -prefix PFC.nii
++ 3dcalc: AFNI version=AFNI_16.3.13 (Nov 23 2016) [64-bit]
++ Authored by: A cast of thousands
** FATAL ERROR: dataset VMPFC.nii differs in size [153594 voxels] from others [902629]
** Program compile date = Nov 23 2016

[S01@NY_Net] $ 3dcalc -a L_VS.nii -b R_VS.nii -c rMPFC.nii -d rVMPFC.nii -expr '(a+b+c+d)' -prefix 4ROI_Merged.nii
++ 3dcalc: AFNI version=AFNI_16.3.13 (Nov 23 2016) [64-bit]
++ Authored by: A cast of thousands
** ERROR (nifti_image_read): failed to find header file for 'rMPFC.nii'
** FATAL ERROR: can't open dataset rMPFC.nii
** Program compile date = Nov 23 2016

[S01@NY_Net] $ 3dcalc -a MPFC.nii -b VMPFC.nii -expr '(a+b)' -prefix PFC.nii
++ 3dcalc: AFNI version=AFNI_16.3.13 (Nov 23 2016) [64-bit]
++ Authored by: A cast of thousands
** FATAL ERROR: dataset VMPFC.nii differs in size [153594 voxels] from others [902629]
** Program compile date = Nov 23 2016