1 files changed, 7 insertions, 1 deletions
diff --git a/param.ccl b/param.ccl
index 7ba4c91..2d192ff 100644
--- a/param.ccl
+++ b/param.ccl
@@ -10,7 +10,13 @@ CCTK_STRING interpolator_name "Which interpolator should I use"
 CCTK_STRING interpolator_pars "Parameters for the interpolator"
 {
     ".*" :: "Any string that Util_TableSetFromString() will take"
-} "order=3"
+} "order=3 boundary_off_centering_tolerance={0.0 0.0 0.0 0.0 0.0 0.0} boundary_extrapolation_tolerance={0.0 0.0 0.0 0.0 0.0 0.0}"
+
+# The above makes sure that the interpolator doesn't off-centre the
+# interpolation stencil if there are insufficient points to
+# interpolate, which can happen if there are insufficient ghost-zones
+# for the interpolation method used, and can lead to processor-number
+# dependent results.
 
 CCTK_STRING coord_system "What is the coord system?"
 {