Greetings,
I am interested in the connection strength of one seed mask against a set of target masks. To achieve this, I have run the following:
probtrackx2 -s bedpostX/merged -m brain_mask -x SeedMast --avoid=ExclusionMask --targetmasks=TargetMaskList --forcedir --opd --dir=ResultsDir --waypoints=TargetMaskList --waycond=OR --os2t --s2tastext -P 25000 --steplength=0.5 --modeuler
The "matrix_seeds_to_all_targets" output text file contains a matrix with as many rows as there were voxels in the seed mask, and as many columns as there were target masks. Running along one row of values should be the waytotal from one seed voxel to each target mask, in turn. Therefore, the sum across columns should always be less than or equal to the value given for "-P", the number of streamlines generated per voxel. Alternatively, the sum across rows should be the waytotal from the entire seed mask to each target mask.
However, I find that the sum across columns is sometimes greater than the value that I gave for "-P". Is there something I've misunderstood about what the values in "matrix_seeds_to_all_targets" mean?
Kind regards,
Jackson Smith
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