$ 3dmaskdump -index -xyz -ibox 123 118 58 \
>                        -ibox 123 119 59 \
>                        -ibox 124 119 59 ~/abin/MNI152_T1_2009c+tlrc
++ 3dmaskdump: AFNI version=AFNI_2011_12_21_1014 (May 13 2015) [64-bit]
++ 8530021 voxels in the entire dataset (no mask)
++ 3 voxels in the boxes and/or balls
++ Using only the boxes+balls mask
2586323 123 118 58 -27 14 -20 173   # voxel I claim MATLAB thinks is at our ijk
2630713 123 119 59 -27 13 -19 170   # voxel I claim MATLAB thinks is at our linear index
2630714 124 119 59 -28 13 -19 171   # voxel we care about
$ matlab -nojvm <<EOF                                                                                                                     
> [err, MNI.brik, MNI.head, msg] = BrikLoad('~/abin/MNI152_T1_2009c+tlrc', struct());
> [~, idx] = AFNI_XYZcontinuous2Index([-28 13 -19], MNI.head)
> matlab_idx = num2cell(idx + 1); idx = num2cell(idx);
> [~, lin_idx] = AFNI_XYZcontinuous2Index([-28 13 -19], MNI.head, [], 1)
> MNI.brik(idx{:})          # give MATLAB the ijk we want
> MNI.brik(lin_idx)         # give MATLAB the linear index we want
> MNI.brik(matlab_idx{:})   # give MATLAB ijk + 1
> MNI.brik(lin_idx + 1)     # give MATLAB linear index + 1
> EOF


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                   R2014b (8.4.0.150421) 64-bit (glnxa64)
                             September 15, 2014

 
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>> >> 
idx =

   124   119    59   # AFNI_XYZcontinuous2Index gives AFNI's ijk index

>> >> 
lin_idx =

     2630714         # AFNI_XYZcontinuous2Index gives AFNI's linear index

>> 
ans =

   173   # but MATLAB hits the wrong voxel when fed ijk

>> 
ans =

   170   # and when fed the linear index

>> 
ans =

   171   # but ijk + 1 works

>> 
ans =

   171   # as does linear index + 1

>>