Removed unnecessary variables in the GIZMO particle definition.

src/hydro/Gizmo/hydro.h

@@ -77,7 +77,6 @@ __attribute__((always_inline)) INLINE static void hydro_init_part(
 
   p->density.wcount = 0.0f;
   p->density.wcount_dh = 0.0f;
-  p->rho = 0.0f;
   p->geometry.volume = 0.0f;
   p->geometry.matrix_E[0][0] = 0.0f;
   p->geometry.matrix_E[0][1] = 0.0f;
@@ -125,9 +124,6 @@ __attribute__((always_inline)) INLINE static void hydro_end_density(
 
   const float ihdim = pow_dimension(ih);
 
-  p->rho += p->mass * kernel_root;
-  p->rho *= ihdim;
-
   float volume;
   float m, momentum[3], energy;
 
@@ -258,12 +254,9 @@ __attribute__((always_inline)) INLINE static void hydro_reset_acceleration(
 __attribute__((always_inline)) INLINE static void hydro_convert_quantities(
     struct part* p) {
 
-  float volume;
-  float m;
   float momentum[3];
-  volume = p->geometry.volume;
-
-  p->conserved.mass = m = p->mass;
+  const float volume = p->geometry.volume;
+  const float m = p->conserved.mass;
   p->primitives.rho = m / volume;
 
   /* P actually contains internal energy at this point */

src/hydro/Gizmo/hydro_iact.h

@@ -57,9 +57,6 @@ __attribute__((always_inline)) INLINE static void runner_iact_density(
   pi->density.wcount += wi;
   pi->density.wcount_dh -= xi * wi_dx;
 
-  /* Density. Needed for h_dt. */
-  pi->rho += pj->mass * wi;
-
   /* these are eqns. (1) and (2) in the summary */
   pi->geometry.volume += wi;
   for (k = 0; k < 3; k++)
@@ -73,9 +70,6 @@ __attribute__((always_inline)) INLINE static void runner_iact_density(
   pj->density.wcount += wj;
   pj->density.wcount_dh -= xj * wj_dx;
 
-  /* Density. Needed for h_dt. */
-  pj->rho += pi->mass * wi;
-
   /* these are eqns. (1) and (2) in the summary */
   pj->geometry.volume += wj;
   for (k = 0; k < 3; k++)
@@ -119,8 +113,6 @@ __attribute__((always_inline)) INLINE static void runner_iact_nonsym_density(
   pi->density.wcount += wi;
   pi->density.wcount_dh -= xi * wi_dx;
 
-  pi->rho += pj->mass * wi;
-
   /* these are eqns. (1) and (2) in the summary */
   pi->geometry.volume += wi;
   for (k = 0; k < 3; k++)
@@ -273,7 +265,7 @@ __attribute__((always_inline)) INLINE static void runner_iact_fluxes_common(
   xj = r * hj_inv;
   kernel_deval(xj, &wj, &wj_dx);
 
-  /* Compute h_dt */
+  /* Compute h_dt. We are going to use an SPH-like estimate of div_v for that */
   float dvdr = (pi->v[0] - pj->v[0]) * dx[0] + (pi->v[1] - pj->v[1]) * dx[1] +
                (pi->v[2] - pj->v[2]) * dx[2];
   float ri = 1.0f / r;
@@ -282,9 +274,9 @@ __attribute__((always_inline)) INLINE static void runner_iact_fluxes_common(
   float wi_dr = hidp1 * wi_dx;
   float wj_dr = hjdp1 * wj_dx;
   dvdr *= ri;
-  pi->force.h_dt -= pj->mass * dvdr / pj->rho * wi_dr;
+  pi->force.h_dt -= pj->conserved.mass * dvdr / pj->primitives.rho * wi_dr;
   if (mode == 1) {
-    pj->force.h_dt -= pi->mass * dvdr / pi->rho * wj_dr;
+    pj->force.h_dt -= pi->conserved.mass * dvdr / pi->primitives.rho * wj_dr;
   }
 
   /* Compute area */
@@ -483,16 +475,32 @@ __attribute__((always_inline)) INLINE static void runner_iact_nonsym_force(
 
 __attribute__((always_inline)) INLINE static void runner_iact_vec_density(
     float *R2, float *Dx, float *Hi, float *Hj, struct part **pi,
-    struct part **pj) {}
+    struct part **pj) {
+  error(
+      "Vectorised versions of the Gizmo interaction functions do not exist "
+      "yet!");
+}
 
 __attribute__((always_inline)) INLINE static void
 runner_iact_nonsym_vec_density(float *R2, float *Dx, float *Hi, float *Hj,
-                               struct part **pi, struct part **pj) {}
+                               struct part **pi, struct part **pj) {
+  error(
+      "Vectorised versions of the Gizmo interaction functions do not exist "
+      "yet!");
+}
 
 __attribute__((always_inline)) INLINE static void runner_iact_vec_force(
     float *R2, float *Dx, float *Hi, float *Hj, struct part **pi,
-    struct part **pj) {}
+    struct part **pj) {
+  error(
+      "Vectorised versions of the Gizmo interaction functions do not exist "
+      "yet!");
+}
 
 __attribute__((always_inline)) INLINE static void runner_iact_nonsym_vec_force(
     float *R2, float *Dx, float *Hi, float *Hj, struct part **pi,
-    struct part **pj) {}
+    struct part **pj) {
+  error(
+      "Vectorised versions of the Gizmo interaction functions do not exist "
+      "yet!");
+}

src/hydro/Gizmo/hydro_io.h

@@ -41,7 +41,7 @@ void hydro_read_particles(struct part* parts, struct io_props* list,
   list[1] = io_make_input_field("Velocities", FLOAT, 3, COMPULSORY,
                                 UNIT_CONV_SPEED, parts, v);
   list[2] = io_make_input_field("Masses", FLOAT, 1, COMPULSORY, UNIT_CONV_MASS,
-                                parts, mass);
+                                parts, conserved.mass);
   list[3] = io_make_input_field("SmoothingLength", FLOAT, 1, COMPULSORY,
                                 UNIT_CONV_LENGTH, parts, h);
   list[4] =

src/hydro/Gizmo/hydro_part.h

 /*******************************************************************************
  * This file is part of SWIFT.
- * Coypright (c) 2012 Pedro Gonnet (pedro.gonnet@durham.ac.uk)
- *                    Matthieu Schaller (matthieu.schaller@durham.ac.uk)
- *                    Bert Vandenbroucke (bert.vandenbroucke@ugent.be)
+ * Coypright (c) 2014 Bert Vandenbroucke (bert.vandenbroucke@ugent.be)
  *
  * 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
@@ -27,10 +25,6 @@ struct xpart {
 
   /* Velocity at the last full step. */
   float v_full[3];
-
-  /* Old density. */
-  float omega;
-
 } __attribute__((aligned(xpart_align)));
 
 /* Data of a single particle. */
@@ -45,7 +39,7 @@ struct part {
   /* Particle acceleration. */
   float a_hydro[3];
 
-  /* Particle cutoff radius. */
+  /* Particle smoothing length. */
   float h;
 
   /* Particle time of beginning of time-step. */
@@ -54,6 +48,9 @@ struct part {
   /* Particle time of end of time-step. */
   int ti_end;
 
+  /* Old internal energy flux */
+  float du_dt;
+
   /* The primitive hydrodynamical variables. */
   struct {
 
@@ -192,19 +189,10 @@ struct part {
 
   } gravity;
 
-  /* Particle mass (this field is also part of the conserved quantities...). */
-  float mass;
-
   /* Particle ID. */
   long long id;
 
   /* Associated gravitas. */
   struct gpart *gpart;
 
-  /* Variables needed for the code to compile (should be removed/replaced). */
-  float rho;
-
-  /* Old internal energy flux */
-  float du_dt;
-
 } __attribute__((aligned(part_align)));