Fix random ray source region mesh export when using model.export_to_xml() (#3579)

Copilot · jtramm · paulromano · web-flow · commit 7806703c2614 · 2025-10-02T22:52:39.000Z
Co-authored-by: copilot-swe-agent[bot] &lt;198982749+Copilot@users.noreply.github.com&gt;
Co-authored-by: jtramm &lt;1009059+jtramm@users.noreply.github.com&gt;
Co-authored-by: Paul Romano &lt;paul.k.romano@gmail.com&gt;
diff --git a/openmc/settings.py b/openmc/settings.py
@@ -1715,9 +1715,15 @@ def _create_random_ray_subelement(self, root, mesh_memo=None):
                             domain_elem = ET.SubElement(mesh_elem, 'domain')
                             domain_elem.set('id', str(domain.id))
                             domain_elem.set('type', domain.__class__.__name__.lower())
-                        if mesh_memo is not None and mesh.id not in mesh_memo:
+                        # See if a <mesh> element already exists -- if not, add it
+                        path = f"./mesh[@id='{mesh.id}']"
+                        if root.find(path) is None:
                             root.append(mesh.to_xml_element())
-                            mesh_memo.add(mesh.id)
+                            if mesh_memo is not None:
+                                mesh_memo.add(mesh.id)
+                elif isinstance(value, bool):
+                    subelement = ET.SubElement(element, key)
+                    subelement.text = str(value).lower()
                 else:
                     subelement = ET.SubElement(element, key)
                     subelement.text = str(value)
@@ -2110,7 +2116,7 @@ def _max_tracks_from_xml_element(self, root):
         if text is not None:
             self.max_tracks = int(text)
 
-    def _random_ray_from_xml_element(self, root):
+    def _random_ray_from_xml_element(self, root, meshes=None):
         elem = root.find('random_ray')
         if elem is not None:
             self.random_ray = {}
@@ -2137,7 +2143,11 @@ def _random_ray_from_xml_element(self, root):
                 elif child.tag == 'source_region_meshes':
                     self.random_ray['source_region_meshes'] = []
                     for mesh_elem in child.findall('mesh'):
-                        mesh = MeshBase.from_xml_element(mesh_elem)
+                        mesh_id = int(get_text(mesh_elem, 'id'))
+                        if meshes and mesh_id in meshes:
+                            mesh = meshes[mesh_id]
+                        else:
+                            mesh = MeshBase.from_xml_element(mesh_elem)
                         domains = []
                         for domain_elem in mesh_elem.findall('domain'):
                             domain_id = int(get_text(domain_elem, "id"))
@@ -2339,7 +2349,7 @@ def from_xml_element(cls, elem, meshes=None):
         settings._max_history_splits_from_xml_element(elem)
         settings._max_tracks_from_xml_element(elem)
         settings._max_secondaries_from_xml_element(elem)
-        settings._random_ray_from_xml_element(elem)
+        settings._random_ray_from_xml_element(elem, meshes)
         settings._use_decay_photons_from_xml_element(elem)
         settings._source_rejection_fraction_from_xml_element(elem)
 
diff --git a/tests/regression_tests/random_ray_adjoint_fixed_source/inputs_true.dat b/tests/regression_tests/random_ray_adjoint_fixed_source/inputs_true.dat
@@ -212,8 +212,8 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
-      <adjoint>True</adjoint>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
+      <adjoint>true</adjoint>
       <volume_estimator>naive</volume_estimator>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_adjoint_k_eff/inputs_true.dat b/tests/regression_tests/random_ray_adjoint_k_eff/inputs_true.dat
@@ -85,8 +85,8 @@
           <parameters>-1.26 -1.26 -1 1.26 1.26 1</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
-      <adjoint>True</adjoint>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
+      <adjoint>true</adjoint>
     </random_ray>
   </settings>
   <tallies>
diff --git a/tests/regression_tests/random_ray_fixed_source_domain/cell/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_domain/cell/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
     </random_ray>
   </settings>
   <tallies>
diff --git a/tests/regression_tests/random_ray_fixed_source_domain/material/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_domain/material/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
     </random_ray>
   </settings>
   <tallies>
diff --git a/tests/regression_tests/random_ray_fixed_source_domain/universe/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_domain/universe/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
     </random_ray>
   </settings>
   <tallies>
diff --git a/tests/regression_tests/random_ray_fixed_source_linear/linear/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_linear/linear/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_shape>linear</source_shape>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_fixed_source_linear/linear_xy/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_linear/linear_xy/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_shape>linear_xy</source_shape>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_fixed_source_mesh/flat/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_mesh/flat/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_region_meshes>
         <mesh id="1">
           <domain id="1" type="universe"/>
diff --git a/tests/regression_tests/random_ray_fixed_source_mesh/linear/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_mesh/linear/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_region_meshes>
         <mesh id="1">
           <domain id="1" type="universe"/>
diff --git a/tests/regression_tests/random_ray_fixed_source_normalization/False/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_normalization/False/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>False</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>false</volume_normalized_flux_tallies>
     </random_ray>
   </settings>
   <tallies>
diff --git a/tests/regression_tests/random_ray_fixed_source_normalization/True/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_normalization/True/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
     </random_ray>
   </settings>
   <tallies>
diff --git a/tests/regression_tests/random_ray_fixed_source_subcritical/flat/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_subcritical/flat/inputs_true.dat
@@ -115,7 +115,7 @@
           <parameters>-1.26 -1.26 -1 1.26 1.26 1</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>False</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>false</volume_normalized_flux_tallies>
       <source_shape>flat</source_shape>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_fixed_source_subcritical/linear_xy/inputs_true.dat b/tests/regression_tests/random_ray_fixed_source_subcritical/linear_xy/inputs_true.dat
@@ -115,7 +115,7 @@
           <parameters>-1.26 -1.26 -1 1.26 1.26 1</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>False</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>false</volume_normalized_flux_tallies>
       <source_shape>linear_xy</source_shape>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_halton_samples/inputs_true.dat b/tests/regression_tests/random_ray_halton_samples/inputs_true.dat
@@ -85,7 +85,7 @@
           <parameters>-1.26 -1.26 -1 1.26 1.26 1</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <sample_method>halton</sample_method>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_k_eff/inputs_true.dat b/tests/regression_tests/random_ray_k_eff/inputs_true.dat
@@ -85,7 +85,7 @@
           <parameters>-1.26 -1.26 -1 1.26 1.26 1</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
     </random_ray>
   </settings>
   <tallies>
diff --git a/tests/regression_tests/random_ray_k_eff_mesh/inputs_true.dat b/tests/regression_tests/random_ray_k_eff_mesh/inputs_true.dat
@@ -85,7 +85,7 @@
           <parameters>-1.26 -1.26 -1 1.26 1.26 1</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_region_meshes>
         <mesh id="2">
           <domain id="7" type="universe"/>
diff --git a/tests/regression_tests/random_ray_linear/linear/inputs_true.dat b/tests/regression_tests/random_ray_linear/linear/inputs_true.dat
@@ -85,7 +85,7 @@
           <parameters>-1.26 -1.26 -1 1.26 1.26 1</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_shape>linear</source_shape>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_linear/linear_xy/inputs_true.dat b/tests/regression_tests/random_ray_linear/linear_xy/inputs_true.dat
@@ -85,7 +85,7 @@
           <parameters>-1.26 -1.26 -1 1.26 1.26 1</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_shape>linear_xy</source_shape>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_low_density/inputs_true.dat b/tests/regression_tests/random_ray_low_density/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
     </random_ray>
   </settings>
   <tallies>
diff --git a/tests/regression_tests/random_ray_point_source_locator/inputs_true.dat b/tests/regression_tests/random_ray_point_source_locator/inputs_true.dat
@@ -211,7 +211,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_region_meshes>
         <mesh id="1">
           <domain id="6" type="universe"/>
diff --git a/tests/regression_tests/random_ray_void/flat/inputs_true.dat b/tests/regression_tests/random_ray_void/flat/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_shape>flat</source_shape>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_void/linear/inputs_true.dat b/tests/regression_tests/random_ray_void/linear/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_shape>linear</source_shape>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_volume_estimator/hybrid/inputs_true.dat b/tests/regression_tests/random_ray_volume_estimator/hybrid/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <volume_estimator>hybrid</volume_estimator>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_volume_estimator/naive/inputs_true.dat b/tests/regression_tests/random_ray_volume_estimator/naive/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <volume_estimator>naive</volume_estimator>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_volume_estimator/simulation_averaged/inputs_true.dat b/tests/regression_tests/random_ray_volume_estimator/simulation_averaged/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <volume_estimator>simulation_averaged</volume_estimator>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/random_ray_volume_estimator_linear/hybrid/inputs_true.dat b/tests/regression_tests/random_ray_volume_estimator_linear/hybrid/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_shape>linear</source_shape>
       <volume_estimator>hybrid</volume_estimator>
     </random_ray>
diff --git a/tests/regression_tests/random_ray_volume_estimator_linear/naive/inputs_true.dat b/tests/regression_tests/random_ray_volume_estimator_linear/naive/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_shape>linear</source_shape>
       <volume_estimator>naive</volume_estimator>
     </random_ray>
diff --git a/tests/regression_tests/random_ray_volume_estimator_linear/simulation_averaged/inputs_true.dat b/tests/regression_tests/random_ray_volume_estimator_linear/simulation_averaged/inputs_true.dat
@@ -212,7 +212,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_shape>linear</source_shape>
       <volume_estimator>simulation_averaged</volume_estimator>
     </random_ray>
diff --git a/tests/regression_tests/weightwindows_fw_cadis/inputs_true.dat b/tests/regression_tests/weightwindows_fw_cadis/inputs_true.dat
@@ -227,7 +227,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <volume_estimator>naive</volume_estimator>
     </random_ray>
   </settings>
diff --git a/tests/regression_tests/weightwindows_fw_cadis_mesh/flat/inputs_true.dat b/tests/regression_tests/weightwindows_fw_cadis_mesh/flat/inputs_true.dat
@@ -227,7 +227,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_region_meshes>
         <mesh id="1">
           <domain id="6" type="universe"/>
diff --git a/tests/regression_tests/weightwindows_fw_cadis_mesh/linear/inputs_true.dat b/tests/regression_tests/weightwindows_fw_cadis_mesh/linear/inputs_true.dat
@@ -227,7 +227,7 @@
           <parameters>0.0 0.0 0.0 30.0 30.0 30.0</parameters>
         </space>
       </source>
-      <volume_normalized_flux_tallies>True</volume_normalized_flux_tallies>
+      <volume_normalized_flux_tallies>true</volume_normalized_flux_tallies>
       <source_region_meshes>
         <mesh id="1">
           <domain id="6" type="universe"/>
diff --git a/tests/unit_tests/test_settings.py b/tests/unit_tests/test_settings.py
@@ -59,12 +59,23 @@ def test_export_to_xml(run_in_tmpdir):
     s.electron_treatment = 'led'
     s.write_initial_source = True
     s.weight_window_checkpoints = {'surface': True, 'collision': False}
+    source_region_mesh = openmc.RegularMesh()
+    source_region_mesh.dimension = [2, 2, 2]
+    source_region_mesh.lower_left = [-2, -2, -2]
+    source_region_mesh.upper_right = [2, 2, 2]
+    root_universe = openmc.Universe()
     s.random_ray = {
         'distance_inactive': 10.0,
         'distance_active': 100.0,
         'ray_source': openmc.IndependentSource(
             space=openmc.stats.Box((-1., -1., -1.), (1., 1., 1.))
-        )
+        ),
+        'source_region_meshes': [(source_region_mesh, [root_universe])],
+        'volume_estimator': 'hybrid',
+        'source_shape': 'linear',
+        'volume_normalized_flux_tallies': True,
+        'adjoint': False,
+        'sample_method': 'halton'
     }
     s.max_particle_events = 100
     s.max_secondaries = 1_000_000
@@ -145,5 +156,17 @@ def test_export_to_xml(run_in_tmpdir):
     assert s.random_ray['distance_active'] == 100.0
     assert s.random_ray['ray_source'].space.lower_left == [-1., -1., -1.]
     assert s.random_ray['ray_source'].space.upper_right == [1., 1., 1.]
+    assert 'source_region_meshes' in s.random_ray
+    assert len(s.random_ray['source_region_meshes']) == 1
+    mesh_and_domains = s.random_ray['source_region_meshes'][0]
+    recovered_mesh = mesh_and_domains[0]
+    assert recovered_mesh.dimension == (2, 2, 2)
+    assert recovered_mesh.lower_left == [-2., -2., -2.]
+    assert recovered_mesh.upper_right == [2., 2., 2.]
+    assert s.random_ray['volume_estimator'] == 'hybrid'
+    assert s.random_ray['source_shape'] == 'linear'
+    assert s.random_ray['volume_normalized_flux_tallies']
+    assert not s.random_ray['adjoint']
+    assert s.random_ray['sample_method'] == 'halton'
     assert s.max_secondaries == 1_000_000
     assert s.source_rejection_fraction == 0.01
