Improve code comments

cheta/derived/comps.py

@@ -665,7 +665,9 @@ def calc_pitch_roll_obc(tstart: float, tstop: float, pitch_roll: str):
     # Pad by 12 minutes on each side to ensure ephemeris data are available.
     tlm = dp.fetch(tstart - 720, tstop + 720)
 
-    # Filter bad data values
+    # Filter bad data values. The `dp.fetch` above sets bad over intervals where any of
+    # the inputs are missing and calling interpolate like below will cut those out.
+    # See PR #250 for more details.
     tlm.interpolate(times=tlm.times)
     tlm.bads = np.zeros(len(tlm.times), dtype=bool)
 
@@ -744,7 +746,8 @@ def get_msid_attrs(self, tstart, tstop, msid, msid_args):
                     tlms.append((np.array([], dtype=float), np.array([], dtype=float)))
                     continue
 
-                # Get states of either NPNT / NMAN or NSUN
+                # Get states of either NPNT / NMAN or NSUN which cover exactly the
+                # time span of the ofp_state interval.
                 vals = np.isin(dat.vals, ["NPNT", "NMAN"])
                 states_npnt_nman = logical_intervals(
                     dat.times,