Add particle_type_to_str and str_to_particle_type functions

include/openmc/particle.h

@@ -157,7 +157,7 @@ public:
   };
 
   //! Saved ("banked") state of a particle
-  //! NOTE: This structure's MPI type is built in initialize_mpi() of 
+  //! NOTE: This structure's MPI type is built in initialize_mpi() of
   //! initialize.cpp. Any changes made to the struct here must also be
   //! made when building the Bank MPI type in initialize_mpi().
   //! NOTE: This structure is also used on the python side, and is defined
@@ -173,7 +173,7 @@ public:
     int64_t parent_id;
     int64_t progeny_id;
   };
-  
+
   //! Saved ("banked") state of a particle, for nu-fission tallying
   struct NuBank {
     double E;  //!< particle energy
@@ -311,7 +311,7 @@ public:
   int cell_born_ {-1};      //!< index for cell particle was born in
   int material_ {-1};       //!< index for current material
   int material_last_ {-1};  //!< index for last material
-  
+
   // Boundary information
   BoundaryInfo boundary_;
 
@@ -328,7 +328,7 @@ public:
   // Current PRNG state
   uint64_t seeds_[N_STREAMS]; // current seeds
   int      stream_;           // current RNG stream
-  
+
   // Secondary particle bank
   std::vector<Particle::Bank> secondary_bank_;
 
@@ -363,6 +363,14 @@ public:
   int64_t n_progeny_ {0}; // Number of progeny produced by this particle
 };
 
+//============================================================================
+//! Functions
+//============================================================================
+
+std::string particle_type_to_str(Particle::Type type);
+
+Particle::Type str_to_particle_type(std::string str);
+
 } // namespace openmc
 
 #endif // OPENMC_PARTICLE_H

src/particle.cpp

@@ -707,4 +707,34 @@ Particle::write_restart() const
   } // #pragma omp critical
 }
 
+std::string particle_type_to_str(Particle::Type type)
+{
+  switch (type) {
+    case Particle::Type::neutron:
+      return "neutron";
+    case Particle::Type::photon:
+      return "photon";
+    case Particle::Type::electron:
+      return "electron";
+    case Particle::Type::positron:
+      return "positron";
+  }
+  UNREACHABLE();
+}
+
+Particle::Type str_to_particle_type(std::string str)
+{
+  if (str == "neutron") {
+    return Particle::Type::neutron;
+  } else if (str == "photon") {
+    return Particle::Type::photon;
+  } else if (str == "electron") {
+    return Particle::Type::electron;
+  } else if (str == "positron") {
+    return Particle::Type::positron;
+  } else {
+    throw std::invalid_argument{fmt::format("Invalid particle name: {}", str)};
+  }
+}
+
 } // namespace openmc

src/physics.cpp

@@ -38,7 +38,7 @@ void collision(Particle& p)
   ++(p.n_collision_);
 
   // Sample reaction for the material the particle is in
-  switch (static_cast<Particle::Type>(p.type_)) {
+  switch (p.type_) {
   case Particle::Type::neutron:
     sample_neutron_reaction(p);
     break;

src/reaction_product.cpp

@@ -5,6 +5,7 @@
 
 #include "openmc/endf.h"
 #include "openmc/hdf5_interface.h"
+#include "openmc/particle.h"
 #include "openmc/random_lcg.h"
 #include "openmc/secondary_correlated.h"
 #include "openmc/secondary_kalbach.h"
@@ -22,11 +23,7 @@ ReactionProduct::ReactionProduct(hid_t group)
   // Read particle type
   std::string temp;
   read_attribute(group, "particle", temp);
-  if (temp == "neutron") {
-    particle_ = Particle::Type::neutron;
-  } else if (temp == "photon") {
-    particle_ = Particle::Type::photon;
-  }
+  particle_ = str_to_particle_type(temp);
 
   // Read emission mode and decay rate
   read_attribute(group, "emission_mode", temp);

src/tallies/filter_particle.cpp

@@ -1,5 +1,7 @@
 #include "openmc/tallies/filter_particle.h"
 
+#include <fmt/core.h>
+
 #include "openmc/xml_interface.h"
 
 namespace openmc {
@@ -12,15 +14,7 @@ ParticleFilter::from_xml(pugi::xml_node node)
   // Convert to vector of Particle::Type
   std::vector<Particle::Type> types;
   for (auto& p : particles) {
-    if (p == "neutron") {
-      types.push_back(Particle::Type::neutron);
-    } else if (p == "photon") {
-      types.push_back(Particle::Type::photon);
-    } else if (p == "electron") {
-      types.push_back(Particle::Type::electron);
-    } else if (p == "positron") {
-      types.push_back(Particle::Type::positron);
-    }
+    types.push_back(str_to_particle_type(p));
   }
   this->set_particles(types);
 }
@@ -57,20 +51,7 @@ ParticleFilter::to_statepoint(hid_t filter_group) const
   Filter::to_statepoint(filter_group);
   std::vector<std::string> particles;
   for (auto p : particles_) {
-    switch (p) {
-    case Particle::Type::neutron:
-      particles.push_back("neutron");
-      break;
-    case Particle::Type::photon:
-      particles.push_back("photon");
-      break;
-    case Particle::Type::electron:
-      particles.push_back("electron");
-      break;
-    case Particle::Type::positron:
-      particles.push_back("positron");
-      break;
-    }
+    particles.push_back(particle_type_to_str(p));
   }
   write_dataset(filter_group, "bins", particles);
 }
@@ -78,17 +59,8 @@ ParticleFilter::to_statepoint(hid_t filter_group) const
 std::string
 ParticleFilter::text_label(int bin) const
 {
-  switch (particles_[bin]) {
-  case Particle::Type::neutron:
-    return "Particle: neutron";
-  case Particle::Type::photon:
-    return "Particle: photon";
-  case Particle::Type::electron:
-    return "Particle: electron";
-  case Particle::Type::positron:
-    return "Particle: positron";
-  }
-  UNREACHABLE();
+  const auto& p = particles_.at(bin);
+  return fmt::format("Particle: {}", particle_type_to_str(p));
 }
 
 } // namespace openmc