Improve impact calc error messages

AUTHORS.md

@@ -28,3 +28,4 @@
 * Lukas Riedel
 * Raphael Portmann
 * Nicolas Colombi
+* Leonie Villiger

CHANGELOG.md

@@ -29,6 +29,7 @@ Removed:
 - Modified the method to disaggregate lines in the `lines_polys_handler` utility module in order to better conserve the total length of all lines on average [#679](https://github.com/CLIMADA-project/climada_python/pull/679).
 - Added test for non-default impact function id in the `lines_polys_handler` [#676](https://github.com/CLIMADA-project/climada_python/pull/676)
 - The sigmoid and step impact functions now require the user to define the hazard type. [#675](https://github.com/CLIMADA-project/climada_python/pull/675)
+- Improved error messages produced by `ImpactCalc.impact()` in case hazard type is not found in exposures/impf_set [#691](https://github.com/CLIMADA-project/climada_python/pull/691)
 
 ### Fixed
 

climada/engine/impact_calc.py

@@ -112,6 +112,22 @@ def impact(self, save_mat=True, assign_centroids=True,
         apply_deductible_to_mat : apply deductible to impact matrix
         apply_cover_to_mat : apply cover to impact matrix
         """
+        # check for compability of exposures and hazard type
+        if all(name not in self.exposures.gdf.columns for
+               name in ['if_', f'if_{self.hazard.haz_type}',
+                        'impf_', f'impf_{self.hazard.haz_type}']):
+            raise AttributeError(
+                "Impact calculation not possible. No impact functions found "
+                f"for hazard type {self.hazard.haz_type} in exposures."
+                )
+
+        # check for compability of impact function and hazard type
+        if not self.impfset.get_func(haz_type=self.hazard.haz_type):
+            raise AttributeError(
+                "Impact calculation not possible. No impact functions found "
+                f"for hazard type {self.hazard.haz_type} in impf_set."
+                )
+
         impf_col = self.exposures.get_impf_column(self.hazard.haz_type)
         exp_gdf = self.minimal_exp_gdf(impf_col, assign_centroids, ignore_cover, ignore_deductible)
         if exp_gdf.size == 0:

climada/engine/test/test_impact_calc.py

@@ -28,7 +28,7 @@
 
 from climada import CONFIG
 from climada.entity.entity_def import Entity
-from climada.entity import Exposures, ImpactFuncSet
+from climada.entity import Exposures, ImpactFuncSet, ImpactFunc
 from climada.hazard.base import Hazard
 from climada.engine import ImpactCalc, Impact
 from climada.engine.impact_calc import LOGGER as ILOG
@@ -101,6 +101,44 @@ def test_apply_cover_to_mat(self):
             imp.todense(), np.array([[0, 0, 1], [0, 1, 0]])
             )
 
+    def test_error_handling_mismatch_haz_type(self):
+        """Test error handling in case hazard type of hazard
+        does not appear in impf_set or exposures"""
+        haz_tc = Hazard('TC')
+        exp_tc = Exposures()
+        exp_tc.gdf['impf_TC'] = None
+        exp_ws = Exposures()
+        exp_ws.gdf['impf_WS'] = None
+        impf = ImpactFunc()
+        impf.id = 1
+        impf.intensity = np.array([0, 20])
+        impf.paa = np.array([0, 1])
+        impf.mdd = np.array([0, 0.5])
+        impf.haz_type = 'TC'
+        impfset_tc = ImpactFuncSet()
+        impfset_tc.append(impf)
+        impf.haz_type = 'WS'
+        impfset_ws = ImpactFuncSet()
+        impfset_ws.append(impf)
+        impf.haz_type = ''
+        impfset_undef = ImpactFuncSet()
+        impfset_undef.append(impf)
+        try:
+            ImpactCalc(exp_ws, impfset_tc, haz_tc).impact()
+        except Exception as e:
+            self.assertEqual(str(e), "Impact calculation not possible. No impact "
+                             "functions found for hazard type TC in exposures.")
+        try:
+            ImpactCalc(exp_tc, impfset_ws, haz_tc).impact()
+        except Exception as e:
+            self.assertEqual(str(e), "Impact calculation not possible. No impact "
+                             "functions found for hazard type TC in impf_set.")
+        try:
+            ImpactCalc(exp_tc, impfset_undef, haz_tc).impact()
+        except Exception as e:
+            self.assertEqual(str(e), "Impact calculation not possible. No impact "
+                             "functions found for hazard type TC in impf_set.")
+
     def test_calc_impact_TC_pass(self):
         """Test compute impact"""
         icalc = ImpactCalc(ENT.exposures, ENT.impact_funcs, HAZ)