Add 3rd order dissipation.

1 files changed, 10 insertions, 0 deletions

diff --git a/src/apply_dissipation.c b/src/apply_dissipation.c
index 6920ef5..ce6e223 100644
--- a/src/apply_dissipation.c
+++ b/src/apply_dissipation.c
@@ -23,6 +23,16 @@ void apply_dissipation(const cGH *gh, const double *var, double *rhs, double dx[
     }
 
     switch (order) {
+    case 3:
+#pragma omp parallel for
+        for (int k = 2; k < nk - 2; k++)
+            for (int i = 2; i < nk - 2; i++) {
+                int idx   = CCTK_GFINDEX3D(gh, i, y_idx, k);
+                rhs[idx] += epsdis[idx] / 16.0 *
+                            ((var[idx - 2]           - 4.0 * var[idx - 1]            + 6.0 * var[idx] - 4.0 * var[idx + 1]           + var[idx + 2]) * inv_dx[0] +
+                             (var[idx - 2 * ni * nj] - 4.0 * var[idx - 1 * ni * nj]  + 6.0 * var[idx] - 4.0 * var[idx + 1 * ni * nj] + var[idx + 2 * ni * nj]) * inv_dx[2]);
+                }
+        break;
     case 5:
 #pragma omp parallel for
         for (int k = 3; k < nk - 3; k++)