Move the multipole acceptance criterion function to a separate file.

src/Makefile.am

@@ -52,7 +52,7 @@ include_HEADERS = space.h runner.h queue.h task.h lock.h cell.h part.h const.h \
     chemistry.h chemistry_io.h chemistry_struct.h cosmology.h restart.h space_getsid.h utilities.h \
     mesh_gravity.h cbrt.h exp10.h velociraptor_interface.h swift_velociraptor_part.h outputlist.h \
     logger_io.h tracers_io.h tracers.h tracers_struct.h star_formation_io.h fof.h fof_struct.h fof_io.h \
-    multipole.h multipole_struct.h binomial.h \
+    multipole.h multipole_accept.h multipole_struct.h binomial.h \
     star_formation_struct.h star_formation.h star_formation_iact.h \
     star_formation_logger.h star_formation_logger_struct.h \
     pressure_floor.h pressure_floor_struct.h pressure_floor_iact.h \

src/cell.c

@@ -61,6 +61,7 @@
 #include "hydro_properties.h"
 #include "memswap.h"
 #include "minmax.h"
+#include "multipole.h"
 #include "pressure_floor.h"
 #include "scheduler.h"
 #include "space.h"

src/engine.c

@@ -75,6 +75,7 @@
 #include "memuse.h"
 #include "minmax.h"
 #include "mpiuse.h"
+#include "multipole_struct.h"
 #include "outputlist.h"
 #include "parallel_io.h"
 #include "part.h"

src/gravity_cache.h

@@ -27,7 +27,7 @@
 #include "align.h"
 #include "error.h"
 #include "gravity.h"
-#include "multipole.h"
+#include "multipole_accept.h"
 #include "vector.h"
 
 /**

src/multipole.h

@@ -44,14 +44,6 @@
 #include "periodic.h"
 #include "vector_power.h"
 
-#ifdef WITH_MPI
-/* MPI datatypes for transfers */
-extern MPI_Datatype multipole_mpi_type;
-extern MPI_Op multipole_mpi_reduce_op;
-void multipole_create_mpi_types(void);
-void multipole_free_mpi_types(void);
-#endif
-
 /**
  * @brief Reset the data of a #multipole.
  *
@@ -2808,65 +2800,4 @@ __attribute__((nonnull)) INLINE static void gravity_L2P(
 #endif
 }
 
-/**
- * @brief Checks whether a cell-cell interaction can be appromixated by a M-M
- * interaction using the distance and cell radius.
- *
- * We use the multipole acceptance criterion of Dehnen, 2002, JCoPh, Volume 179,
- * Issue 1, pp.27-42, equation 10.
- *
- * We also additionally check that the distance between the multipoles
- * is larger than the softening lengths (here the distance at which
- * the gravity becomes Newtonian again, not the Plummer-equivalent quantity).
- *
- * @param r_crit_a The size of the multipole A.
- * @param r_crit_b The size of the multipole B.
- * @param theta_crit2 The square of the critical opening angle.
- * @param r2 Square of the distance (periodically wrapped) between the
- * multipoles.
- * @param epsilon_a The maximal softening length of any particle in A.
- * @param epsilon_b The maximal softening length of any particle in B.
- */
-__attribute__((always_inline, const)) INLINE static int gravity_M2L_accept(
-    const double r_crit_a, const double r_crit_b, const double theta_crit2,
-    const double r2, const double epsilon_a, const double epsilon_b) {
-
-  const double size = r_crit_a + r_crit_b;
-  const double size2 = size * size;
-  const double epsilon_a2 = epsilon_a * epsilon_a;
-  const double epsilon_b2 = epsilon_b * epsilon_b;
-
-  // MATTHIEU: Make this mass-dependent ?
-
-  /* Multipole acceptance criterion (Dehnen 2002, eq.10) */
-  return (r2 * theta_crit2 > size2) && (r2 > epsilon_a2) && (r2 > epsilon_b2);
-}
-
-/**
- * @brief Checks whether a particle-cell interaction can be appromixated by a
- * M2P interaction using the distance and cell radius.
- *
- * We use the multipole acceptance criterion of Dehnen, 2002, JCoPh, Volume 179,
- * Issue 1, pp.27-42, equation 10.
- *
- * We also additionally check that the distance between the particle and the
- * multipole is larger than the softening length (here the distance at which
- * the gravity becomes Newtonian again, not the Plummer-equivalent quantity).
- *
- * @param r_max2 The square of the size of the multipole.
- * @param theta_crit2 The square of the critical opening angle.
- * @param r2 Square of the distance (periodically wrapped) between the
- * particle and the multipole.
- * @param epsilon The softening length of the particle.
- */
-__attribute__((always_inline, const)) INLINE static int gravity_M2P_accept(
-    const float r_max2, const float theta_crit2, const float r2,
-    const float epsilon) {
-
-  // MATTHIEU: Make this mass-dependent ?
-
-  /* Multipole acceptance criterion (Dehnen 2002, eq.10) */
-  return (r2 * theta_crit2 > r_max2) && (r2 > epsilon * epsilon);
-}
-
 #endif /* SWIFT_MULTIPOLE_H */

src/multipole_accept.h

+/*******************************************************************************
+ * This file is part of SWIFT.
+ * Copyright (c) 2016 Matthieu Schaller (schaller@strw.leidenuniv.nl)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ ******************************************************************************/
+#ifndef SWIFT_MULTIPOLE_ACCEPT_H
+#define SWIFT_MULTIPOLE_ACCEPT_H
+
+/* Config parameters. */
+#include "../config.h"
+
+/* Local includes */
+#include "multipole_struct.h"
+
+/**
+ * @brief Checks whether a cell-cell interaction can be appromixated by a M-M
+ * interaction using the distance and cell radius.
+ *
+ * We use the multipole acceptance criterion of Dehnen, 2002, JCoPh, Volume 179,
+ * Issue 1, pp.27-42, equation 10.
+ *
+ * We also additionally check that the distance between the multipoles
+ * is larger than the softening lengths (here the distance at which
+ * the gravity becomes Newtonian again, not the Plummer-equivalent quantity).
+ *
+ * @param r_crit_a The size of the multipole A.
+ * @param r_crit_b The size of the multipole B.
+ * @param theta_crit2 The square of the critical opening angle.
+ * @param r2 Square of the distance (periodically wrapped) between the
+ * multipoles.
+ * @param epsilon_a The maximal softening length of any particle in A.
+ * @param epsilon_b The maximal softening length of any particle in B.
+ */
+__attribute__((always_inline, const)) INLINE static int gravity_M2L_accept(
+    const double r_crit_a, const double r_crit_b, const double theta_crit2,
+    const double r2, const double epsilon_a, const double epsilon_b) {
+
+  const double size = r_crit_a + r_crit_b;
+  const double size2 = size * size;
+  const double epsilon_a2 = epsilon_a * epsilon_a;
+  const double epsilon_b2 = epsilon_b * epsilon_b;
+
+  // MATTHIEU: Make this mass-dependent ?
+
+  /* Multipole acceptance criterion (Dehnen 2002, eq.10) */
+  return (r2 * theta_crit2 > size2) && (r2 > epsilon_a2) && (r2 > epsilon_b2);
+}
+
+/**
+ * @brief Checks whether a particle-cell interaction can be appromixated by a
+ * M2P interaction using the distance and cell radius.
+ *
+ * We use the multipole acceptance criterion of Dehnen, 2002, JCoPh, Volume 179,
+ * Issue 1, pp.27-42, equation 10.
+ *
+ * We also additionally check that the distance between the particle and the
+ * multipole is larger than the softening length (here the distance at which
+ * the gravity becomes Newtonian again, not the Plummer-equivalent quantity).
+ *
+ * @param r_max2 The square of the size of the multipole.
+ * @param theta_crit2 The square of the critical opening angle.
+ * @param r2 Square of the distance (periodically wrapped) between the
+ * particle and the multipole.
+ * @param epsilon The softening length of the particle.
+ */
+__attribute__((always_inline, const)) INLINE static int gravity_M2P_accept(
+    const float r_max2, const float theta_crit2, const float r2,
+    const float epsilon) {
+
+  // MATTHIEU: Make this mass-dependent ?
+
+  /* Multipole acceptance criterion (Dehnen 2002, eq.10) */
+  return (r2 * theta_crit2 > r_max2) && (r2 > epsilon * epsilon);
+}
+
+#endif /* SWIFT_MULTIPOLE_ACCEPT_H */

src/multipole_struct.h

@@ -230,4 +230,13 @@ struct reduced_grav_tensor {
   float F_001;
 };
 
+#ifdef WITH_MPI
+/* MPI datatypes for transfers */
+extern MPI_Datatype multipole_mpi_type;
+extern MPI_Op multipole_mpi_reduce_op;
+
+void multipole_create_mpi_types(void);
+void multipole_free_mpi_types(void);
+#endif
+
 #endif /* SWIFT_MULTIPOLE_STRUCT_H */

src/runner_time_integration.c

@@ -32,6 +32,7 @@
 #include "engine.h"
 #include "feedback.h"
 #include "kick.h"
+#include "multipole.h"
 #include "timers.h"
 #include "timestep.h"
 #include "timestep_limiter.h"