Routine to check if grid sizes and ghost_zones are enough for the order of

finite differencing requires. Has not been tested thoroughly.


git-svn-id: https://svn.cct.lsu.edu/repos/numrel/LSUThorns/SummationByParts/trunk@16 f69c4107-0314-4c4f-9ad4-17e986b73f4a

1 files changed, 54 insertions, 0 deletions

diff --git a/src/CheckGridSizes.F90 b/src/CheckGridSizes.F90
new file mode 100644
index 0000000..3240f6a
--- /dev/null
+++ b/src/CheckGridSizes.F90
@@ -0,0 +1,54 @@
+! Check if there are enough grid cells and ghost zones to compute the finite
+! differences.
+! $Header$
+
+#include "cctk.h"
+#include "cctk_Parameters.h"
+#include "cctk_Arguments.h"
+#include "cctk_Functions.h"
+
+subroutine SBP_CheckGridSizes(CCTK_ARGUMENTS)
+
+  implicit none
+
+  DECLARE_CCTK_PARAMETERS
+  DECLARE_CCTK_ARGUMENTS
+  DECLARE_CCTK_FUNCTIONS
+
+  integer :: i
+  integer, dimension(3) :: bc
+  integer, dimension(3,3) :: np
+  character(len=128) :: info_message
+  character(len=1), dimension(3) :: dir = (/ 'x', 'y', 'z' /)
+
+  bc(1) = cctk_bbox(1)+cctk_bbox(2)+1    ! 0 processor boundaries -> bc = 3
+  bc(2) = cctk_bbox(3)+cctk_bbox(4)+1    ! 1 processor boundary -> bc = 2
+  bc(3) = cctk_bbox(5)+cctk_bbox(6)+1    ! 2 processor boundaries -> bc = 1
+
+  if ( any (cctk_nghostzones < order / 2) .and. CCTK_nProcs(cctkGH) > 1 )  then
+    write(info_message,'(a22,i1,a13,i1,a25)') 'You need ghostsize >= ', &
+                                    order/2, ' to run with ', order, &
+                                    ' order finite differences'
+    call CCTK_WARN(0,info_message)
+  end if
+
+  if ( CCTK_EQUALS(norm_type,"Diagonal") ) then
+    np(1,:) = 2*cctk_nghostzones
+    np(2,:) = 3*order/2
+    np(3,:) = 2*order
+  else
+    np(1,:) = 2*cctk_nghostzones
+    np(2,:) = 3*order/2 + 1
+    np(3,:) = 2*(order+1)
+  end if
+    
+  do i = 1, 3 
+    if ( cctk_lsh(i) < np(bc(i),i) ) then
+      write(info_message,'(a27,a1,a35,i1,a25)') &
+         'Your local gridsize in the ', dir(i), &
+         '-direction is to small to run with ', order, &
+         ' order finite differences'
+      call CCTK_WARN(0,info_message)
+    end if
+  end do
+end subroutine SBP_CheckGridSizes