Add a head function for ObsTable

Author: jeremykubica

src/lightcurvelynx/obstable/obs_table.py

@@ -226,6 +226,10 @@ def copy(self):
             **new_survey_values,
         )
 
+    def head(self, n=5):
+        """Return the first n rows of the observation table."""
+        return self._table.head(n)
+
     def uses_footprint(self):
         """Return whether the ObsTable uses a detector footprint for filtering."""
         return self._detector_footprint is not None

tests/lightcurvelynx/obstable/test_obs_table.py

@@ -61,6 +61,10 @@ def test_create_obs_table():
     # Without a filters column we cannot access the filters.
     assert len(ops_data.filters) == 0
 
+    # Check the head function.
+    assert len(ops_data.head(3)) == 3
+    assert len(ops_data.head(10)) == 5
+
     # We can create an ObsTable directly from the dictionary as well.
     ops_data2 = ObsTable(pdf)
     assert len(ops_data2) == 5