fix bug

git-svn-id: http://svn.einsteintoolkit.org/cactus/EinsteinAnalysis/Hydro_Analysis/trunk@33 b6729ddc-ac74-4bd1-908c-9dc7244c52a1

1 files changed, 43 insertions, 0 deletions

diff --git a/src/Hydro_Analysis.c b/src/Hydro_Analysis.c
index 7d182ea..3f1e3f2 100644
--- a/src/Hydro_Analysis.c
+++ b/src/Hydro_Analysis.c
@@ -77,3 +77,46 @@ void Hydro_Analysis_LocationSearch(CCTK_ARGUMENTS)
 {
   DECLARE_CCTK_ARGUMENTS
   DECLARE_CCTK_PARAMETERS
+
+  /* Initialized MPI-local quantities */
+  CCTK_REAL local_rho_max_loc[3];
+  local_rho_max_loc[0] = 0.0;
+  local_rho_max_loc[1] = 0.0;
+  local_rho_max_loc[2] = 0.0;
+
+  /* Look for the location of the global maximum.
+   * This algorithm will have problems when that occurs at more than
+   * one location. */
+  #pragma omp parallel
+  {
+    LC_LOOP3(location_reduction, i,j,k,
+             cctk_nghostzones[0], cctk_nghostzones[1], cctk_nghostzones[2],
+             cctk_lsh[0] - cctk_nghostzones[0], cctk_lsh[1] - cctk_nghostzones[1],
+             cctk_lsh[2] - cctk_nghostzones[2], cctk_lsh[0], cctk_lsh[1], cctk_lsh[2])
+    {
+      CCTK_INT i3D = CCTK_GFINDEX3D(cctkGH, i, j, k);
+      if (rho[i3D] == *Hydro_Analysis_rho_max &&
+          (!Hydro_Analysis_rho_max_loc_only_positive_x || x[i3D] >= 0.0))
+      {
+        #pragma omp critical
+        {
+          local_rho_max_loc[0] = x[i3D];
+          local_rho_max_loc[1] = y[i3D];
+          local_rho_max_loc[2] = z[i3D];
+        }
+      }
+    }
+    LC_ENDLOOP3(location_reduction);
+  }
+  /* After this at least one MPI process should have the location set.
+   * The others should have a value of 0.0, so that the sum reduction
+   * gives the value on each MPI process. This however is not true sometimes
+   * and this is the point where the algorithm can fail. */
+  CCTK_INT handle_sum = CCTK_LocalArrayReductionHandle("sum");
+  if (handle_sum < 0)
+     CCTK_WARN(0, "Unable to get reduction handle 'sum'.");
+  if (CCTK_ReduceLocArrayToArray1D(cctkGH, -1, handle_sum, &local_rho_max_loc,
+                                   Hydro_Analysis_rho_max_loc, 3, CCTK_VARIABLE_REAL))
+    CCTK_WARN(0, "Error while reducing local_rho_max_loc");
+}
+