+The tracker data file one can read with Tracker::read has the
+following format (with L the number of locations and T the number of
+time steps):
+
+---------------------------- snip snip -------------------------------
+L T
+
+allowed_motion_from_1_to_1 ... allowed_motion_from_1_to_L
+...
+allowed_motion_from_L_to_1 ... allowed_motion_from_L_to_L
+
+is_an_entrance_1 ... is_an_entrance_L
+
+is_an_exit_1 ... is_an_exit_L
+
+detection_score_1_1 ... detection_score_1_L
+...
+detection_score_T_1 ... detection_score_T_L
+---------------------------- snip snip -------------------------------
+