Resolve "Hit amplitude not available when reading offline data"

km3io/offline.py

@@ -41,7 +41,7 @@ class OfflineReader(EventReader):
             "dir_y": "hits.dir.y",
             "dir_z": "hits.dir.z",
             "tot": "hits.tot",
-            "a": "mc_hits.a",  # hit amplitude (in p.e.)
+            "a": "hits.a",  # hit amplitude (in p.e.)
             "trig": "hits.trig",  # non-zero if the hit is a triggered hit
         },
         "mc_hits": {

tests/test_offline.py

@@ -406,6 +406,7 @@ class TestOfflineHits(unittest.TestCase):
         assert "channel_id" in self.hits.fields
         assert "t" in self.hits.fields
         assert "tot" in self.hits.fields
+        assert "a" in self.hits.fields
         assert "trig" in self.hits.fields
         assert "id" in self.hits.fields