#include <stdio.h>
#include <stdlib.h>
#include <shmem.h>
	static float *upper, *middle, *lower;
	void initval( float *p[], float *rhs[], int nrows, int ncols,
		      float pborder, float pinside, float rhsborder, float rhsinside )
{
	int i, j;
/***/
	for ( i = 0; i < nrows; i++ )
	 {
	  for ( j = 0; j < ncols; j++ )
	   {
	    if ( (i == 0) || (j == 0) || 
	         (i == (nrows-1)) || (j == (ncols-1)) )
	     {
	      p[i][j] = pborder;
	      rhs[i][j] = rhsborder;
	     }	 
	    else
	     {
	      p[i][j] = pinside;
	      rhs[i][j] = rhsinside;
	     } 
	   }
	 } 
}
	void allocate( int nrows, int ncols, float **pcop, float **corhs )
{
	upper = emalloc( ncols*sizeof(*upper) );
	middle = emalloc( ncols*sizeof(*middle) );
	lower = emalloc( ncols*sizeof(*lower) );
	if ( (!upper) || (!middle) || (!lower) )
	 {
	  printf( "Cannot allocate\n" );
	 }
} 
	void upload( float *p[], float *rhs[], int nrows, int ncols,
		      float *cop, float *corhs )
{
} 
	void download( float *p[], float *rhs[], int nrows, int ncols,
		      float *cop, float *corhs )
{
} 
	void poissn( float *p[], float *rhs[], float **pcop, int icop, float *corhs,
		      int nrows, int ncols, float delx, float dely, float addcoeff[] )
{
	int i, j, k;
	float rdx2, rdy2, beta2, result;
/***/
	rdx2 = 1./delx/delx;
	rdy2 = 1./dely/dely;
	beta2 = 1.0/(2.0*(rdx2+rdy2)); 
	for ( j = 0; j < ncols; j++ )
	 {
	  upper[j] = p[0][j];
	  middle[j] = p[1][j];
	 }
	for ( i = 2; i < nrows; i++ )
	 {
	  for ( j = 0; j < ncols; j++ ) lower[j] = p[i][j];
	  for ( j = 1; j < (ncols-1); j++ )
	   {
	    p[i-1][j]  = beta2*(
		    (upper[j]+lower[j])*rdx2
		  + (middle[j+1]+middle[j-1])*rdy2
		  - rhs[i-1][j]);    
	   }
	  for ( j = 0; j < ncols; j++ )
	   {
	    upper[j] = middle[j];
	    middle[j] = lower[j];
	   } 
	 }     
}