Add option to load pointing information with TableLoader, fixes #1900

ctapipe/io/tableloader.py

@@ -21,6 +21,7 @@
 IMAGES_GROUP = "/dl1/event/telescope/images"
 GEOMETRY_GROUP = "/dl2/event/subarray/geometry"
 TRIGGER_TABLE = "/dl1/event/subarray/trigger"
+POINTING_TABLE = "/dl1/monitoring/subarray/pointing"
 SHOWER_TABLE = "/simulation/event/subarray/shower"
 TRUE_IMAGES_GROUP = "/simulation/event/telescope/images"
 TRUE_PARAMETERS_GROUP = "/simulation/event/telescope/parameters"
@@ -110,6 +111,9 @@ class TableLoader(Component):
     load_instrument = traits.Bool(
         False, help="join subarray instrument information to each event"
     ).tag(config=True)
+    load_pointings = traits.Bool(False, help="join subarray pointings information").tag(
+        config=True
+    )
 
     def __init__(self, input_url=None, **kwargs):
         # enable using input_url as posarg
@@ -172,6 +176,15 @@ def _read_telescope_table(self, group, tel_id):
 
         return table
 
+    def _join_interp_pointings(self, table, pointings):
+        for col in set(pointings.colnames) - set(["time"]):
+            table[col] = np.interp(
+                table["time"].mjd, pointings["time"].mjd, pointings[col]
+            ).astype(pointings[col].dtype)
+            table[col].unit = pointings[col].unit
+
+        return table
+
     def read_subarray_events(self):
         """Read subarray-based event information.
 
@@ -186,6 +199,14 @@ def read_subarray_events(self):
             trigger = read_table(self.h5file, TRIGGER_TABLE)
             table = join_allow_empty(table, trigger, SUBARRAY_EVENT_KEYS, "outer")
 
+        if self.load_pointings:
+            if not self.load_trigger:
+                trigger = read_table(self.h5file, TRIGGER_TABLE)
+                table = join_allow_empty(table, trigger, SUBARRAY_EVENT_KEYS, "outer")
+                table.remove_columns(["tels_with_trigger", "event_type"])
+            pointings = read_table(self.h5file, POINTING_TABLE)
+            table = self._join_interp_pointings(table, pointings)
+
         if self.load_simulated and SHOWER_TABLE in self.h5file:
             showers = read_table(self.h5file, SHOWER_TABLE)
             table = join_allow_empty(table, showers, SUBARRAY_EVENT_KEYS, "outer")
@@ -303,7 +324,16 @@ def read_telescope_events(self, telescopes=None):
 
         table = self._read_telescope_events_for_ids(tel_ids)
 
-        if any([self.load_trigger, self.load_simulated, self.load_dl2_geometry]):
+        # TODO: load telescope trigger and pointing tables instead of appending the
+        # subarray one
+        if any(
+            [
+                self.load_trigger,
+                self.load_simulated,
+                self.load_dl2_geometry,
+                self.load_pointings,
+            ]
+        ):
             table = self._join_subarray_info(table)
 
         return table
@@ -336,7 +366,14 @@ def read_telescope_events_by_type(self, telescopes=None) -> Dict[str, Table]:
 
         by_type = {k: vstack(ts) for k, ts in by_type.items()}
 
-        if any([self.load_trigger, self.load_simulated, self.load_dl2_geometry]):
+        if any(
+            [
+                self.load_trigger,
+                self.load_simulated,
+                self.load_dl2_geometry,
+                self.load_pointings,
+            ]
+        ):
             for key, table in by_type.items():
                 by_type[key] = self._join_subarray_info(table)
 

ctapipe/io/tests/test_table_loader.py

@@ -113,7 +113,6 @@ def test_true_parameters(test_file):
 
 def test_read_subarray_events(test_file_dl2):
     """Test reading subarray events"""
-
     from ctapipe.io.tableloader import TableLoader
 
     _, dl2_file = test_file_dl2
@@ -127,9 +126,19 @@ def test_read_subarray_events(test_file_dl2):
         assert "time" in table.colnames
 
 
+def test_pointings(test_file):
+    """Test joining true_parameters pointing information onto subarray events"""
+    from ctapipe.io.tableloader import TableLoader
+
+    _, dl1_file = test_file
+
+    with TableLoader(dl1_file, load_pointings=True, load_trigger=False) as table_loader:
+        table = table_loader.read_subarray_events()
+        assert "array_altitude" in table.colnames
+
+
 def test_read_telescope_events_type(test_file_dl2):
     """Test reading telescope events for a given telescope type"""
-
     from ctapipe.io.tableloader import TableLoader
 
     _, dl2_file = test_file_dl2
@@ -156,7 +165,6 @@ def test_read_telescope_events_type(test_file_dl2):
 
 def test_read_telescope_events_by_type(test_file_dl2):
     """Test reading telescope events for by types"""
-
     from ctapipe.io.tableloader import TableLoader
 
     _, dl2_file = test_file_dl2