Raise exception when L3 stereo event number jumps backwards for more than 100...

Raise exception when L3 stereo event number jumps backwards for more than 100 events (like in MARS).

ctapipe_io_magic/__init__.py

@@ -64,6 +64,13 @@ MC_TRIGGER_PATTERN = 1
 PEDESTAL_TRIGGER_PATTERN = 8
 DATA_TRIGGER_PATTERN = 128
 
+class L3JumpError(Exception):
+    """
+    Exception raised when L3 trigger number jumps backward.
+    """
+
+    def __init__(self, message):
+        self.message = message
 
 class MAGICEventSource(EventSource):
     """
@@ -1259,12 +1266,20 @@ class MarsRun:
                 dx_flip_ids_after = np.array(
                     list(set(dx_flip_ids_after) - set(orphan_ids)))
             dx_flip_ids_before = dx_flip_ids_after - 1
+            max_total_jumps = 100
             if len(dx_flip_ids_before) > 0:
                 LOGGER.warning("Warning: detected %d bitflips in file %s. Flag affected events as unsuitable" % (
                     len(dx_flip_ids_before), file_name))
+                total_jumped_events = 0
                 for i in dx_flip_ids_before:
                     trigger_pattern[i] = -1
                     trigger_pattern[i+1] = -1
+                    jumped_events = int(stereo_event_number[i]) - int(stereo_event_number[i+1])
+                    total_jumped_events += jumped_events
+                    LOGGER.warning(f"Jump of L3 number backward from {stereo_event_number[i]} to {stereo_event_number[i+1]}; "
+                        f"total jumped events so far: {total_jumped_events}")
+                    if total_jumped_events > max_total_jumps:
+                        raise L3JumpError(f"Jumps backward in L3 trigger number by {total_jumped_events} in total. You might consider matching events by time instead.")
 
             event_data['charge'].append(charge)
             event_data['arrival_time'].append(arrival_time)