FACTID-based tractography code, from Taylor, Cho, Lin and Biswal (2012),
part of FATCAT (Taylor & Saad, 2013) in AFNI.

Estimate locations of WM associated with GM ROIs, particularly between
pairs of GM in a network;  can process several networks in a given run.

!!All usage has been migrated to 3dTrackID (with modes to select for
  deterministic, mini-probabilistic and full probabilistic tracking).

So get thee hence;  see '3dTrackid -help' for all options, and consider
  downloading and installing the latest version of the FATCAT demo set
  for lots of examples, scripts and descriptions: @Install_FATCAT_DEMO.