I’m experiencing some unexpected behavior from tck2connectome when using the -scale_* options. I have a whole brain seeded .tck file to which I’m applying a custom atlas created from a series spherical ROIs merged into a single nifti file. When I use the -scale_invnodevol option, I get reasonable looking results with all nodes assigned at least one streamline. However, if I drop that option (calculating just the sum of streamlines for each edge) or apply the combo -scale_length -stat_edge mean options, no streamlines are assigned to any nodes.
Shouldn’t these options just change the weight of the entries in the connectivity matrix? If connection is nonzero with one scale option, it should be nonzero with another, no?