It works! Replaced all mgxs_header functionality with the C++ version and a mgxs_interface module to act as the go-between the C++ and Fortran

src/mgxs_interface.cpp

@@ -0,0 +1,247 @@
+#include "mgxs_interface.h"
+
+namespace openmc {
+
+//==============================================================================
+// Mgxs data loading interface methods
+//==============================================================================
+
+void add_mgxs_c(hid_t file_id, char* name, int energy_groups,
+     int delayed_groups, int n_temps, double temps[], int& method,
+     double tolerance, int max_order, bool legendre_to_tabular,
+     int legendre_to_tabular_points)
+{
+  //!! mgxs_data.F90 will be modified to just create the list of names
+  //!! in the order needed
+  // Convert temps to a vector for the from_hdf5 function
+  double_1dvec temperature;
+  temperature.assign(temps, temps + n_temps);
+
+  // TODO: C++ replacement for write_message
+  // write_message("Loading " + std::string(names[i]) + " data...", 6);
+
+  // Check to make sure cross section set exists in the library
+  hid_t xs_grp;
+  if (object_exists(file_id, name)) {
+    xs_grp = open_group(file_id, name);
+  } else {
+    fatal_error("Data for " + std::string(name) + " does not exist in "
+                + "provided MGXS Library");
+  }
+
+  Mgxs mg;
+  mg.from_hdf5(xs_grp, energy_groups, delayed_groups,
+       temperature, method, tolerance, max_order, legendre_to_tabular,
+       legendre_to_tabular_points);
+
+  nuclides_MG.push_back(mg);
+}
+
+
+bool query_fissionable_c(const int n_nuclides, const int i_nuclides[])
+{
+  bool result = false;
+  for (int n = 0; n < n_nuclides; n++) {
+    if (nuclides_MG[i_nuclides[n] - 1].fissionable) result = true;
+  }
+  return result;
+}
+
+
+void create_macro_xs_c(char* mat_name, const int n_nuclides,
+     const int i_nuclides[], const int n_temps, const double temps[],
+     const double atom_densities[], int& method, const double tolerance)
+{
+  Mgxs macro;
+  if (n_temps > 0) {
+    // // Convert temps to a vector
+    double_1dvec temperature;
+    temperature.assign(temps, temps + n_temps);
+
+    // Convert atom_densities to a vector
+    double_1dvec atom_densities_vec;
+    atom_densities_vec.assign(atom_densities, atom_densities + n_nuclides);
+
+    // Build array of pointers to nuclides_MG's Mgxs objects needed for this
+    // material
+    std::vector<Mgxs*> mgxs_ptr(n_nuclides);
+    for (int n = 0; n < n_nuclides; n++) {
+      mgxs_ptr[n] = &nuclides_MG[i_nuclides[n] - 1];
+    }
+
+    macro.build_macro(mat_name, temperature, mgxs_ptr, atom_densities_vec,
+         method, tolerance);
+  }
+  macro_xs.push_back(macro);
+}
+
+//==============================================================================
+// Mgxs tracking/transport/tallying interface methods
+//==============================================================================
+
+void calculate_xs_c(const int i_mat, const int gin, const double sqrtkT,
+     const double uvw[3], double& total_xs, double& abs_xs, double& nu_fiss_xs)
+{
+  macro_xs[i_mat - 1].calculate_xs(gin - 1, sqrtkT, uvw, total_xs, abs_xs,
+       nu_fiss_xs);
+}
+
+
+void sample_scatter_c(const int i_mat, const int gin, int& gout, double& mu,
+     double& wgt, double uvw[3])
+{
+  int gout_c = gout - 1;
+  macro_xs[i_mat - 1].sample_scatter(gin - 1, gout_c, mu, wgt);
+
+  // adjust return value for fortran indexing
+  gout = gout_c + 1;
+
+  // Rotate the angle
+  rotate_angle_c(uvw, mu, nullptr);
+}
+
+
+void sample_fission_energy_c(const int i_mat, const int gin, int& dg, int& gout)
+{
+  int dg_c = 0;
+  int gout_c = 0;
+  macro_xs[i_mat - 1].sample_fission_energy(gin - 1, dg_c, gout_c);
+
+  // adjust return values for fortran indexing
+  dg = dg_c + 1;
+  gout = gout_c + 1;
+}
+
+
+void get_name_c(const int index, int name_len, char* name)
+{
+  // First blank out our input string
+  std::string str(name_len, ' ');
+  std::strcpy(name, str.c_str());
+
+  // Now get the data and copy to the C-string
+  str = nuclides_MG[index - 1].name;
+  std::strcpy(name, str.c_str());
+
+  // Finally, remove the null terminator
+  name[std::strlen(name)] = ' ';
+}
+
+
+double get_awr_c(const int index)
+{
+  return nuclides_MG[index - 1].awr;
+}
+
+
+double get_nuclide_xs_c(const int index, const int xstype, const int gin,
+     int* gout, double* mu, int* dg)
+{
+  int gout_c;
+  int* gout_c_p;
+  int dg_c;
+  int* dg_c_p;
+  if (gout != nullptr) {
+    gout_c = *gout - 1;
+    gout_c_p = &gout_c;
+  } else {
+    gout_c_p = gout;
+  }
+  if (dg != nullptr) {
+    dg_c = *dg - 1;
+    dg_c_p = &dg_c;
+  } else {
+    dg_c_p = dg;
+  }
+  return nuclides_MG[index - 1].get_xs(xstype, gin - 1, gout_c_p, mu, dg_c_p);
+}
+
+
+double get_macro_xs_c(const int index, const int xstype, const int gin,
+     int* gout, double* mu, int* dg)
+{
+  int gout_c;
+  int* gout_c_p;
+  int dg_c;
+  int* dg_c_p;
+  if (gout != nullptr) {
+    gout_c = *gout - 1;
+    gout_c_p = &gout_c;
+  } else {
+    gout_c_p = gout;
+  }
+  if (dg != nullptr) {
+    dg_c = *dg - 1;
+    dg_c_p = &dg_c;
+  } else {
+    dg_c_p = dg;
+  }
+  return macro_xs[index - 1].get_xs(xstype, gin - 1, gout_c_p, mu, dg_c_p);
+}
+
+
+void set_nuclide_angle_index_c(const int index, const double uvw[3],
+     int& last_pol, int& last_azi, double last_uvw[3])
+{
+  // Store the old
+  last_pol = nuclides_MG[index - 1].index_pol;
+  last_azi = nuclides_MG[index - 1].index_azi;
+  last_uvw[0] = nuclides_MG[index - 1].last_uvw[0];
+  last_uvw[1] = nuclides_MG[index - 1].last_uvw[1];
+  last_uvw[2] = nuclides_MG[index - 1].last_uvw[2];
+
+  // Update the values
+  nuclides_MG[index - 1].set_angle_index(uvw);
+}
+
+
+void reset_nuclide_angle_index_c(const int index, const int last_pol,
+     const int last_azi, const double last_uvw[3])
+{
+  nuclides_MG[index - 1].index_pol = last_pol;
+  nuclides_MG[index - 1].index_azi = last_azi;
+  nuclides_MG[index - 1].last_uvw[0] = last_uvw[0];
+  nuclides_MG[index - 1].last_uvw[1] = last_uvw[1];
+  nuclides_MG[index - 1].last_uvw[2] = last_uvw[2];
+}
+
+
+void set_macro_angle_index_c(const int index, const double uvw[3],
+     int& last_pol, int& last_azi, double last_uvw[3])
+{
+  // Store the old
+  last_pol = macro_xs[index - 1].index_pol;
+  last_azi = macro_xs[index - 1].index_azi;
+  last_uvw[0] = macro_xs[index - 1].last_uvw[0];
+  last_uvw[1] = macro_xs[index - 1].last_uvw[1];
+  last_uvw[2] = macro_xs[index - 1].last_uvw[2];
+
+  // Update the values
+  macro_xs[index - 1].set_angle_index(uvw);
+}
+
+
+void reset_macro_angle_index_c(const int index, const int last_pol,
+     const int last_azi, const double last_uvw[3])
+{
+  macro_xs[index - 1].index_pol = last_pol;
+  macro_xs[index - 1].index_azi = last_azi;
+  macro_xs[index - 1].last_uvw[0] = last_uvw[0];
+  macro_xs[index - 1].last_uvw[1] = last_uvw[1];
+  macro_xs[index - 1].last_uvw[2] = last_uvw[2];
+}
+
+
+int set_nuclide_temperature_index_c(const int index, const double sqrtkT)
+{
+  int old = nuclides_MG[index - 1].index_temp;
+  nuclides_MG[index - 1].set_temperature_index(sqrtkT);
+  return old;
+}
+
+void reset_nuclide_temperature_index_c(const int index, const int last_temp)
+{
+  nuclides_MG[index - 1].index_temp = last_temp;
+}
+
+} // namespace openmc