From 115be68953b30e64aa886c55db13b0e9d212f3c5 Mon Sep 17 00:00:00 2001
From: NybergWISC <mnyberg@wisc.edu>
Date: Mon, 15 Aug 2022 09:30:57 -0500
Subject: [PATCH] Small refactor of distribution_spatial.cpp and change default
 of volume_normalized to True

---
 openmc/stats/multivariate.py                  |  2 +-
 src/distribution_spatial.cpp                  | 33 ++++++++-----------
 .../unstructured_mesh/source_sampling/test.py |  4 ++-
 3 files changed, 17 insertions(+), 22 deletions(-)

diff --git a/openmc/stats/multivariate.py b/openmc/stats/multivariate.py
index 9aa03b2d7f..88beea2f7e 100644
--- a/openmc/stats/multivariate.py
+++ b/openmc/stats/multivariate.py
@@ -643,7 +643,7 @@ class MeshSpatial(Spatial):
 
     """
 
-    def __init__(self, mesh, strengths=None, volume_normalized=False):
+    def __init__(self, mesh, strengths=None, volume_normalized=True):
         self.mesh = mesh        
         self.strengths = strengths
         self.volume_normalized = volume_normalized
diff --git a/src/distribution_spatial.cpp b/src/distribution_spatial.cpp
index 6d00739b06..b47b85281d 100644
--- a/src/distribution_spatial.cpp
+++ b/src/distribution_spatial.cpp
@@ -212,34 +212,27 @@ MeshSpatial::MeshSpatial(pugi::xml_node node)
   // Volume scheme is weighted by the volume of each tet
   // File scheme is weighted by an array given in the xml file
 
+  mesh_strengths_ = std::vector<double>(tot_bins_, 1.0);
   if (check_for_node(node, "strengths")) {
-    mesh_strengths_ = get_node_array<double>(node, "strengths");
-    if (mesh_strengths_.size() != tot_bins_){
-      fatal_error("The size of the strengths array from the xml file does not equal the number of elements in the mesh.");
-    } if (get_node_value_bool(node, "volume_normalized")){
-      for (int i = 0; i < tot_bins_; i++){
-        strengths[i] = mesh_strengths_[i]*mesh_ptr_->volume(i);
-      } 
-    } else if (!get_node_value_bool(node, "volume_normalized")){
-      for (int i = 0; i < tot_bins_; i++){
-        strengths[i] = mesh_strengths_[i];  
+      strengths = get_node_array<double>(node, "strengths");
+      if (strengths.size() != mesh_strengths_.size()){
+        fatal_error("Number of entries in the strength matrix does not match the number of mesh entities");
       }
-    }
-  } else if (get_node_value_bool(node, "volume_normalized")){
-    for (int i = 0; i<tot_bins_; i++){
-      strengths[i] = mesh_ptr_->volume(i);
-    }
-  } else {
-    for (int i = 0; i<tot_bins_; i++){
-      strengths[i] = 1;
+      mesh_strengths_ = strengths;
+  }
+
+  if (get_node_value_bool(node, "volume_normalized")) {
+    for (int i = 0; i < tot_bins_; i++) {
+      mesh_strengths_[i] *= mesh_ptr_->volume(i);
     }
   }
+
   for (int i = 0; i<tot_bins_; i++){
-    temp_total_strength = temp_total_strength + strengths[i];
+    temp_total_strength = temp_total_strength + mesh_strengths_[i];
   }
   total_strength_ = temp_total_strength;
   for (int i = 0; i<tot_bins_; i++){
-    mesh_CDF_[i+1] = mesh_CDF_[i] + strengths[i]/total_strength_;
+    mesh_CDF_[i+1] = mesh_CDF_[i] + mesh_strengths_[i]/total_strength_;
   }
 }
 
diff --git a/tests/regression_tests/unstructured_mesh/source_sampling/test.py b/tests/regression_tests/unstructured_mesh/source_sampling/test.py
index 6f8d6fded2..46d1e0cb08 100644
--- a/tests/regression_tests/unstructured_mesh/source_sampling/test.py
+++ b/tests/regression_tests/unstructured_mesh/source_sampling/test.py
@@ -35,7 +35,9 @@ class UnstructuredMeshSourceTest(PyAPITestHarness):
         average_in_hex = 10.0
 
         # Load in tracks
-        openmc.Tracks.combine(glob.glob('tracks_p*.h5'))
+        if config['mpi']:
+            openmc.Tracks.combine(glob.glob('tracks_p*.h5'))
+        
         tracks = openmc.Tracks(filepath='tracks.h5')
         tracks_born = np.empty((len(tracks), 1))