examples/smpi/NAS/LU/neighbors.f

   1
   2 c---------------------------------------------------------------------
   3 c---------------------------------------------------------------------
   4
   5       subroutine neighbors ()
   6
   7 c---------------------------------------------------------------------
   8 c---------------------------------------------------------------------
   9
  10       implicit none
  11
  12       include 'applu.incl'
  13
  14 c---------------------------------------------------------------------
  15 c     figure out the neighbors and their wrap numbers for each processor
  16 c---------------------------------------------------------------------
  17
  18         south = -1
  19         east  = -1
  20         north = -1
  21         west  = -1
  22
  23       if (row.gt.1) then
  24               north = id -1
  25       else
  26               north = -1
  27       end if
  28
  29       if (row.lt.xdim) then
  30               south = id + 1
  31       else
  32               south = -1
  33       end if
  34
  35       if (col.gt.1) then
  36               west = id- xdim
  37       else
  38               west = -1
  39       end if
  40
  41       if (col.lt.ydim) then
  42               east = id + xdim
  43       else
  44               east = -1
  45       end if
  46
  47       return
  48       end