add sanity checks (#988)

Python/site-packages/sv_rom_extract_results/post.py

@@ -194,11 +194,20 @@ def project_results_to_centerline(self):
         # centerline points
         points = v2n(self.geos['cent'].GetPoints().GetData())
 
+        # all branch ids in centerline
+        ids_cent = np.unique(arrays_cent['BranchId']).tolist()
+        ids_cent.remove(-1)
+
         # loop all result fields
         for f in self.params.data_names:
             if f not in self.results:
                 continue
 
+            # check if ROM branch has same ids as centerline
+            ids_rom = list(self.results[f].keys())
+            ids_rom.sort()
+            assert ids_cent == ids_rom, 'Centerline and ROM results have different branch ids'
+
             # initialize output arrays
             array_f = np.zeros((arrays_cent['Path'].shape[0], len(self.params.times)))
             n_outlet = np.zeros(arrays_cent['Path'].shape[0])
@@ -222,9 +231,17 @@ def project_results_to_centerline(self):
 
                     # map results to branches
                     path_1d_res, f_res = res_rom_to_path(path_centerline, res_br)
+                else:
+                    raise ValueError('Unknown ROM model order ' + str(self.params.model_order))
 
-                # map 1d results to centerline using paths
-                f_cent = interp1d(path_1d_res, f_res.T, fill_value='extrapolate')(path_cent).T
+                assert np.isclose(path_1d_res[0], 0.0), 'ROM branch path does not start at 0'
+                assert np.isclose(path_cent[0], 0.0), 'Centerline branch path does not start at 0'
+                msg = 'ROM results and centerline have different branch path lengths'
+                assert np.isclose(path_1d_res[-1], path_cent[-1]), msg
+
+                # interpolate ROM onto centerline
+                # limit to interval [0,1] to avoid extrapolation error interp1d due to slightly incompatible lenghts
+                f_cent = interp1d(path_1d_res / path_1d_res[-1], f_res.T)(path_cent / path_cent[-1]).T
 
                 # store results of this path
                 array_f[arrays_cent['BranchId'] == br] = f_cent[:, self.params.time_indices]
@@ -260,9 +277,11 @@ def project_results_to_centerline(self):
                 elif self.params.model_order == 1:
                     f0 = res_br_u[sorted(res_br_u.keys())[-1]][-1][self.params.time_indices]
                     f1 = res_br[0][0][self.params.time_indices]
+                else:
+                    raise ValueError('Unknown ROM model order ' + str(self.params.model_order))
 
                 # map 1d results to centerline using paths
-                array_f[jc_cent] += interp1d([0, 1], np.vstack((f0, f1)).T, fill_value='extrapolate')(jc_path).T
+                array_f[jc_cent] += interp1d([0, 1], np.vstack((f0, f1)).T)(jc_path).T
 
                 # count number of outlets of this junction
                 n_outlet[jc_cent] += 1