core: Use aggregate initialization

src/core/electrostatics_magnetostatics/coulomb.cpp

@@ -139,15 +139,10 @@ void deactivate() {
     break;
 #endif
   case COULOMB_DH:
-    dh_params.r_cut = 0.0;
-    dh_params.kappa = 0.0;
+    dh_params = {};
     break;
   case COULOMB_RF:
-    rf_params.kappa = 0.0;
-    rf_params.epsilon1 = 0.0;
-    rf_params.epsilon2 = 0.0;
-    rf_params.r_cut = 0.0;
-    rf_params.B = 0.0;
+    rf_params = {};
     break;
   case COULOMB_MMM1D:
     mmm1d_params.maxPWerror = 1e40;

src/core/electrostatics_magnetostatics/debye_hueckel.cpp

@@ -35,12 +35,10 @@ Debye_hueckel_params dh_params{};
 void dh_set_params(double kappa, double r_cut) {
   if (kappa < 0.0)
     throw std::domain_error("kappa should be a non-negative number");
-
   if (r_cut < 0.0)
     throw std::domain_error("r_cut should be a non-negative number");
 
-  dh_params.kappa = kappa;
-  dh_params.r_cut = r_cut;
+  dh_params = {r_cut, kappa};
 
   mpi_bcast_coulomb_params();
 }

src/core/electrostatics_magnetostatics/debye_hueckel.hpp

@@ -33,12 +33,12 @@
 #include <cmath>
 
 /** Structure to hold Debye-Hueckel parameters. */
-typedef struct {
+struct Debye_hueckel_params {
   /** Cutoff for Debye-Hueckel interaction. */
   double r_cut;
   /** Debye kappa (inverse Debye length) . */
   double kappa;
-} Debye_hueckel_params;
+};
 
 /** Debye-Hueckel parameters. */
 extern Debye_hueckel_params dh_params;

src/core/electrostatics_magnetostatics/reaction_field.cpp

@@ -40,14 +40,11 @@ void rf_set_params(double kappa, double epsilon1, double epsilon2,
   if (r_cut < 0.0)
     throw std::domain_error("r_cut should be a non-negative number");
 
-  rf_params.kappa = kappa;
-  rf_params.epsilon1 = epsilon1;
-  rf_params.epsilon2 = epsilon2;
-  rf_params.r_cut = r_cut;
-  rf_params.B = (2 * (epsilon1 - epsilon2) * (1 + kappa * r_cut) -
-                 epsilon2 * kappa * kappa * r_cut * r_cut) /
-                ((epsilon1 + 2 * epsilon2) * (1 + kappa * r_cut) +
-                 epsilon2 * kappa * kappa * r_cut * r_cut);
+  auto const B = (2 * (epsilon1 - epsilon2) * (1 + kappa * r_cut) -
+                  epsilon2 * kappa * kappa * r_cut * r_cut) /
+                 ((epsilon1 + 2 * epsilon2) * (1 + kappa * r_cut) +
+                  epsilon2 * kappa * kappa * r_cut * r_cut);
+  rf_params = {kappa, epsilon1, epsilon2, r_cut, B};
 
   mpi_bcast_coulomb_params();
 }

src/core/electrostatics_magnetostatics/reaction_field.hpp

@@ -35,7 +35,7 @@
 #include <utils/math/int_pow.hpp>
 
 /** Structure to hold Reaction Field Parameters. */
-typedef struct {
+struct Reaction_field_params {
   /** ionic strength. */
   double kappa;
   /** epsilon1 (continuum dielectric constant inside). */
@@ -46,7 +46,7 @@ typedef struct {
   double r_cut;
   /** B important prefactor. */
   double B;
-} Reaction_field_params;
+};
 
 /** Structure containing the Reaction Field parameters. */
 extern Reaction_field_params rf_params;