Dear AFNI helpers,
I have a question about how to rank activity values on a voxel-specific level, rather than across all voxels.
I have 30 activity maps for each subject, so there are 30 unique betas per voxel. For each individual voxel in the subject’s brain map, I need rank the betas across the 30 maps, and determine the rank of each voxel in map #1, relative to the other 29, and then assign this rank to the voxel.
So, the output would be a brain map with the ranking of map# 1's value at every voxel. I guess this would be like doing 3dRank across all input datasets, but on a voxel-by-voxel basis.
Does anyone have any advice on how to accomplish this in AFNI? I know I can calculate the max and median on a voxel-by-voxel basis in 3dalc, but I’m wondering how to do this kind of ranking.
Thanks in advance,
Lisa
