IMPLICIT DOUBLE PRECISION (A-H,O-Z)
      INCLUDE 'mpif.h'
* The next line is only required for MPICH <= 1.2.1
*      INCLUDE 'mpiof.h'
      INTEGER RTYPE
      PARAMETER (RTYPE=MPI_DOUBLE_PRECISION)
*
***      IMPLICIT REAL (A-H,O-Z)
***      INCLUDE 'mpif.h'
***      INCLUDE 'mpiof.h'
***      INTEGER RTYPE
***      PARAMETER (RTYPE=MPI_REAL)
*
* NPROCS:		total number of processors
* NP, NQ:		processor grid, NP*NQ = NPROCS
* COMM:			communicator with 2D Cartesian topology
* RANK_X, RANK_Y:	Cartesian coordinates in COMM.
* MYRANK:		my rank in COMM
* NGLOB, MGLOB: 	total grid points
* NLOCA, MLOCA: 	local grid points
* IOFFSET, JOFFSET:	coordinates of lower-left corner in the global grid.
* NSAVE:		save solution every NSAVE iterations.
* XTYPE:		datatype representing (1:N-1,.)
* YTYPE:		datatype representing (.,1:M-1)
* LEFT, RIGHT:		neighbors in the x direction
* UPPER, LOWER:		neighbors in the y direction
*
      INTEGER NPROCS, NP, NQ, MYRANK, NGLOB, MGLOB, NLOCA, MLOCA,
     +        COMM, RANK_X, RANK_Y, IOFFSET, JOFFSET, NSAVE,
     +        XTYPE, YTYPE, LEFT, RIGHT, UPPER, LOWER
      COMMON /PARMS/ NPROCS, NP, NQ, MYRANK, NGLOB, MGLOB, NLOCA, MLOCA,
     +               COMM, RANK_X, RANK_Y, IOFFSET, JOFFSET, NSAVE,
     +               XTYPE, YTYPE, LEFT, RIGHT, UPPER, LOWER