From multiple requests, as well as for my own plans, want to split functionality across three commands:

• fixelconnectivity: Generate the fixel-fixel connectivity matrix, normalise / threshold, and save to file (need to determine an appropriate format).

• fixelsmooth: Smooth fixel-based data using both fixel-fixel connectivity and spatial proximity. Depending on the time required to re-load the fixel connectivity matrix into memory, may be preferable to input a text file containing paths to fixel data files, and smooth them all in one go, writing the result to a duplicate fixel directory, so that the matrix need only be loaded once per cohort.

• fixelcfestats: Take as input pre-smoothed data. Will also make interface more consistent with mrclusterstats, which expects pre-smoothed data.