Converts a bids_h5_study_dataset (or any fmri_study_dataset)
to an fmri_group object with one row per subject. Use this when you
need per-subject group operations via group_map().
Converts a bids_h5_study_dataset (or any fmri_study_dataset)
to an fmri_group object with one row per subject. Use this when you
need per-subject group operations via group_map().