C-API bindings for key random ray functions (#3749)

docs/source/capi/index.rst

@@ -601,6 +601,10 @@ Functions
    :return: Return status (negative if an error occurs)
    :rtype: int
 
+.. c:function:: void openmc_run_random_ray()
+
+   Run a random ray simulation
+
 .. c:function:: int openmc_set_n_batches(int32_t n_batches, bool set_max_batches, bool add_statepoint_batch)
 
    Set number of batches and number of max batches

docs/source/pythonapi/capi.rst

@@ -40,6 +40,7 @@ Functions
    reset_timers
    run
    run_in_memory
+   run_random_ray
    sample_external_source
    simulation_finalize
    simulation_init

include/openmc/capi.h

@@ -140,6 +140,7 @@ int openmc_remove_tally(int32_t index);
 int openmc_reset();
 int openmc_reset_timers();
 int openmc_run();
+void openmc_run_random_ray();
 int openmc_sample_external_source(size_t n, uint64_t* seed, void* sites);
 void openmc_set_seed(int64_t new_seed);
 void openmc_set_stride(uint64_t new_stride);

include/openmc/random_ray/random_ray_simulation.h

@@ -66,10 +66,9 @@ private:
 //! Non-member functions
 //============================================================================
 
-void openmc_run_random_ray();
 void validate_random_ray_inputs();
-void openmc_reset_random_ray();
 void print_adjoint_header();
+void openmc_finalize_random_ray();
 
 } // namespace openmc
 

openmc/lib/core.py

@@ -82,6 +82,7 @@ _dll.openmc_properties_import.restype = c_int
 _dll.openmc_properties_import.errcheck = _error_handler
 _dll.openmc_run.restype = c_int
 _dll.openmc_run.errcheck = _error_handler
+_dll.openmc_run_random_ray.restype = None
 _dll.openmc_reset.restype = c_int
 _dll.openmc_reset.errcheck = _error_handler
 _dll.openmc_reset_timers.restype = c_int
@@ -479,6 +480,18 @@ def run(output=True):
         _dll.openmc_run()
 
 
+def run_random_ray(output=True):
+    """Run a random ray simulation
+
+    Parameters
+    ----------
+    output : bool, optional
+        Whether or not to show output. Defaults to showing output
+    """
+
+    with quiet_dll(output):
+        _dll.openmc_run_random_ray()
+
 def sample_external_source(
         n_samples: int = 1000,
         prn_seed: int | None = None

src/finalize.cpp

@@ -122,6 +122,7 @@ int openmc_finalize()
   settings::restart_run = false;
   settings::run_CE = true;
   settings::run_mode = RunMode::UNSET;
+  settings::solver_type = SolverType::MONTE_CARLO;
   settings::source_latest = false;
   settings::source_rejection_fraction = 0.05;
   settings::source_separate = false;
@@ -184,7 +185,7 @@ int openmc_finalize()
   }
 #endif
 
-  openmc_reset_random_ray();
+  openmc_finalize_random_ray();
 
   return 0;
 }

src/random_ray/random_ray_simulation.cpp

@@ -1,5 +1,6 @@
 #include "openmc/random_ray/random_ray_simulation.h"
 
+#include "openmc/capi.h"
 #include "openmc/eigenvalue.h"
 #include "openmc/geometry.h"
 #include "openmc/message_passing.h"
@@ -22,49 +23,6 @@ namespace openmc {
 // Non-member functions
 //==============================================================================
 
-void openmc_run_random_ray()
-{
-  //////////////////////////////////////////////////////////
-  // Run forward simulation
-  //////////////////////////////////////////////////////////
-
-  if (mpi::master) {
-    if (FlatSourceDomain::adjoint_) {
-      FlatSourceDomain::adjoint_ = false;
-      openmc::print_adjoint_header();
-      FlatSourceDomain::adjoint_ = true;
-    }
-  }
-
-  // Initialize OpenMC general data structures
-  openmc_simulation_init();
-
-  // Validate that inputs meet requirements for random ray mode
-  if (mpi::master)
-    validate_random_ray_inputs();
-
-  // Initialize Random Ray Simulation Object
-  RandomRaySimulation sim;
-
-  // Initialize fixed sources, if present
-  sim.apply_fixed_sources_and_mesh_domains();
-
-  // Run initial random ray simulation
-  sim.simulate();
-
-  //////////////////////////////////////////////////////////
-  // Run adjoint simulation (if enabled)
-  //////////////////////////////////////////////////////////
-
-  if (sim.adjoint_needed_) {
-    // Setup for adjoint simulation
-    sim.prepare_adjoint_simulation();
-
-    // Run adjoint simulation
-    sim.simulate();
-  }
-}
-
 // Enforces restrictions on inputs in random ray mode.  While there are
 // many features that don't make sense in random ray mode, and are therefore
 // unsupported, we limit our testing/enforcement operations only to inputs
@@ -283,17 +241,6 @@ void validate_random_ray_inputs()
   }
 }
 
-void openmc_reset_random_ray()
-{
-  FlatSourceDomain::volume_estimator_ = RandomRayVolumeEstimator::HYBRID;
-  FlatSourceDomain::volume_normalized_flux_tallies_ = false;
-  FlatSourceDomain::adjoint_ = false;
-  FlatSourceDomain::mesh_domain_map_.clear();
-  RandomRay::ray_source_.reset();
-  RandomRay::source_shape_ = RandomRaySourceShape::FLAT;
-  RandomRay::sample_method_ = RandomRaySampleMethod::PRNG;
-}
-
 void print_adjoint_header()
 {
   if (!FlatSourceDomain::adjoint_)
@@ -670,4 +617,62 @@ void RandomRaySimulation::print_results_random_ray(
   }
 }
 
+void openmc_finalize_random_ray()
+{
+  FlatSourceDomain::volume_estimator_ = RandomRayVolumeEstimator::HYBRID;
+  FlatSourceDomain::volume_normalized_flux_tallies_ = false;
+  FlatSourceDomain::adjoint_ = false;
+  FlatSourceDomain::mesh_domain_map_.clear();
+  RandomRay::ray_source_.reset();
+  RandomRay::source_shape_ = RandomRaySourceShape::FLAT;
+  RandomRay::sample_method_ = RandomRaySampleMethod::PRNG;
+}
+
 } // namespace openmc
+
+//==============================================================================
+// C API functions
+//==============================================================================
+
+void openmc_run_random_ray()
+{
+  //////////////////////////////////////////////////////////
+  // Run forward simulation
+  //////////////////////////////////////////////////////////
+
+  if (openmc::mpi::master) {
+    if (openmc::FlatSourceDomain::adjoint_) {
+      openmc::FlatSourceDomain::adjoint_ = false;
+      openmc::print_adjoint_header();
+      openmc::FlatSourceDomain::adjoint_ = true;
+    }
+  }
+
+  // Initialize OpenMC general data structures
+  openmc_simulation_init();
+
+  // Validate that inputs meet requirements for random ray mode
+  if (openmc::mpi::master)
+    openmc::validate_random_ray_inputs();
+
+  // Initialize Random Ray Simulation Object
+  openmc::RandomRaySimulation sim;
+
+  // Initialize fixed sources, if present
+  sim.apply_fixed_sources_and_mesh_domains();
+
+  // Run initial random ray simulation
+  sim.simulate();
+
+  //////////////////////////////////////////////////////////
+  // Run adjoint simulation (if enabled)
+  //////////////////////////////////////////////////////////
+
+  if (sim.adjoint_needed_) {
+    // Setup for adjoint simulation
+    sim.prepare_adjoint_simulation();
+
+    // Run adjoint simulation
+    sim.simulate();
+  }
+}

tests/unit_tests/test_lib.py

@@ -5,6 +5,7 @@ import os
 import numpy as np
 import pytest
 import openmc
+from openmc.examples import random_ray_pin_cell
 import openmc.exceptions as exc
 import openmc.lib
 
@@ -83,6 +84,19 @@ def uo2_trigger_model():
         yield
 
 
+@pytest.fixture(scope='module')
+def random_ray_pincell_model():
+    """Set up a random ray model to test with and delete files when done"""
+    openmc.reset_auto_ids()
+    # Write XML and MGXS files in tmpdir
+    with cdtemp():
+        model = random_ray_pin_cell()
+        model.settings.batches = 200
+        model.settings.inactive = 50
+        model.settings.particles = 50
+        model.export_to_xml()
+        yield
+
 @pytest.fixture(scope='module')
 def lib_init(pincell_model, mpi_intracomm):
     openmc.lib.init(intracomm=mpi_intracomm)
@@ -1052,3 +1066,15 @@ def test_sample_external_source(run_in_tmpdir, mpi_intracomm):
     openmc.lib.init(["-c"])
     openmc.lib.sample_external_source(100)
     openmc.lib.finalize()
+
+
+def test_random_ray(random_ray_pincell_model, mpi_intracomm):
+    openmc.lib.finalize()
+    openmc.lib.init(intracomm=mpi_intracomm)
+    openmc.lib.simulation_init()
+    openmc.lib.run_random_ray()
+    keff = openmc.lib.keff()
+
+    assert keff[0]==pytest.approx(1.3236826574065745)
+
+    openmc.lib.finalize()