/*************************************************************************/
/*                                                                       */
/*  Copyright (c) 1994 Stanford University                               */
/*                                                                       */
/*  All rights reserved.                                                 */
/*                                                                       */
/*  Permission is given to use, copy, and modify this software for any   */
/*  non-commercial purpose as long as this copyright notice is not       */
/*  removed.  All other uses, including redistribution in whole or in    */
/*  part, are forbidden without prior written permission.                */
/*                                                                       */
/*  This software is provided with absolutely no warranty and no         */
/*  support.                                                             */
/*                                                                       */
/*************************************************************************/

/*    ****************
      subroutine slave
      ****************  */
     
EXTERN_ENV

#include <stdio.h>
#include <math.h>
#include <time.h>
#include "decs.h"

void slave() 

{
   int i;
   int j;
   int nstep;
   int iindex;
   int iday;
   double ysca1;
   double y;
   double factor;
   double sintemp;
   double curlt;
   double ressqr;
   int istart; 
   int iend; 
   int jstart; 
   int jend;
   int ist; 
   int ien; 
   int jst; 
   int jen;
   double fac;
   int dayflag=0;
   int dhourflag=0;
   int endflag=0;
   int firstrow;
   int lastrow;
   int numrows;
   int firstcol;
   int lastcol;
   int numcols;
   int psiindex;
   double psibipriv;
   double ttime;
   double dhour;
   double day;
   int procid;
   int psinum;
   int i_off = 0;
   int j_off = 0;
   unsigned long t1;
   double **t2a;
   double **t2b;
   double *t1a;
   double *t1b;
   double *t1c;
   double *t1d;

   ressqr = lev_res[numlev-1] * lev_res[numlev-1];

   LOCK(locks->idlock)
     procid = global->id;
     global->id = global->id+1;
   UNLOCK(locks->idlock)     

   BARRIER(bars->sl_prini,nprocs)

/* POSSIBLE ENHANCEMENT:  Here is where one might pin processes to
   processors to avoid migration. */

/* POSSIBLE ENHANCEMENT:  Here is where one might distribute 
   data structures across physically distributed memories as
   desired.
   
   One way to do this is as follows.  The function allocate(START,SIZE,I)
   is assumed to place all addresses x such that 
   (START <= x < START+SIZE) on node I.

   int d_size;
   unsigned int g_size;
   unsigned int mg_size;

   if (procid == MASTER) {
     g_size = ((jmx[numlev-1]-2)/xprocs+2)*((imx[numlev-1]-2)/yprocs+2)*siz
eof(double) +
              ((imx[numlev-1]-2)/yprocs+2)*sizeof(double *);

     mg_size = numlev*sizeof(double **);
     for (i=0;i<numlev;i++) {
       mg_size+=((imx[i]-2)/yprocs+2)*((jmx[i]-2)/xprocs+2)*sizeof(double)+
                ((imx[i]-2)/yprocs+2)*sizeof(double *);
     }
     for (i= 0;i<nprocs;i++) {
       d_size = 2*sizeof(double **);
       allocate((unsigned int) psi[i],d_size,i);
       allocate((unsigned int) psim[i],d_size,i);
       allocate((unsigned int) work1[i],d_size,i);
       allocate((unsigned int) work4[i],d_size,i);
       allocate((unsigned int) work5[i],d_size,i);
       allocate((unsigned int) work7[i],d_size,i);
       allocate((unsigned int) temparray[i],d_size,i);
       allocate((unsigned int) psi[i][0],g_size,i);
       allocate((unsigned int) psi[i][1],g_size,i);
       allocate((unsigned int) psim[i][0],g_size,i);
       allocate((unsigned int) psim[i][1],g_size,i);
       allocate((unsigned int) psium[i],g_size,i);
       allocate((unsigned int) psilm[i],g_size,i);
       allocate((unsigned int) psib[i],g_size,i);
       allocate((unsigned int) ga[i],g_size,i);
       allocate((unsigned int) gb[i],g_size,i);
       allocate((unsigned int) work1[i][0],g_size,i);
       allocate((unsigned int) work1[i][1],g_size,i);
       allocate((unsigned int) work2[i],g_size,i);
       allocate((unsigned int) work3[i],g_size,i);
       allocate((unsigned int) work4[i][0],g_size,i);
       allocate((unsigned int) work4[i][1],g_size,i);
       allocate((unsigned int) work5[i][0],g_size,i);
       allocate((unsigned int) work5[i][1],g_size,i);
       allocate((unsigned int) work6[i],g_size,i);
       allocate((unsigned int) work7[i][0],g_size,i);
       allocate((unsigned int) work7[i][1],g_size,i);
       allocate((unsigned int) temparray[i][0],g_size,i);
       allocate((unsigned int) temparray[i][1],g_size,i);
       allocate((unsigned int) tauz[i],g_size,i);
       allocate((unsigned int) oldga[i],g_size,i);
       allocate((unsigned int) oldgb[i],g_size,i);
       d_size = numlev * sizeof(int);
       allocate((unsigned int) gp[i].rel_num_x,d_size,i);
       allocate((unsigned int) gp[i].rel_num_y,d_size,i);
       allocate((unsigned int) gp[i].eist,d_size,i);
       allocate((unsigned int) gp[i].ejst,d_size,i);
       allocate((unsigned int) gp[i].oist,d_size,i);
       allocate((unsigned int) gp[i].ojst,d_size,i);
       allocate((unsigned int) gp[i].rlist,d_size,i);
       allocate((unsigned int) gp[i].rljst,d_size,i);
       allocate((unsigned int) gp[i].rlien,d_size,i);
       allocate((unsigned int) gp[i].rljen,d_size,i);

       allocate((unsigned int) q_multi[i],mg_size,i);
       allocate((unsigned int) rhs_multi[i],mg_size,i);
       allocate((unsigned int) &(gp[i]),sizeof(struct Global_Private),i);
     }
   }

*/

   t2a = (double **) oldga[procid];
   t2b = (double **) oldgb[procid];
   for (i=0;i<im;i++) {
     t1a = (double *) t2a[i];
     t1b = (double *) t2b[i];
     for (j=0;j<jm;j++) {
        t1a[j] = 0.0;
        t1b[j] = 0.0;
     }
   }

   firstcol = 1;
   lastcol = firstcol + gp[procid].rel_num_x[numlev-1] - 1;
   firstrow = 1;
   lastrow = firstrow + gp[procid].rel_num_y[numlev-1] - 1;  
   numcols = gp[procid].rel_num_x[numlev-1];
   numrows = gp[procid].rel_num_y[numlev-1];
   j_off = gp[procid].colnum*numcols;

   if (procid > nprocs/2) {
      psinum = 2;
   } else {
      psinum = 1;
   }

/* every process gets its own copy of the timing variables to avoid
   contention at shared memory locations.  here, these variables
   are initialized.  */

   ttime = 0.0;
   dhour = 0.0;
   nstep = 0 ;
   day = 0.0;

   ysca1 = 0.5*ysca;
   if (procid == MASTER) {
     t1a = (double *) f;
     for (iindex = 0;iindex<=jmx[numlev-1]-1;iindex++) {
       y = ((double) iindex)*res;
       t1a[iindex] = f0+beta*(y-ysca1);
     }
   }

   t2a = (double **) psium[procid];
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     t2a[0][0]=0.0;
   }  
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     t2a[im-1][0]=0.0;
   }
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     t2a[0][jm-1]=0.0;
   }
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     t2a[im-1][jm-1]=0.0;
   }
   if (gp[procid].neighbors[UP] == -1) {
     t1a = (double *) t2a[0];
     for(j=firstcol;j<=lastcol;j++) {
       t1a[j] = 0.0;
     }
   }
   if (gp[procid].neighbors[DOWN] == -1) {
     t1a = (double *) t2a[im-1];
     for(j=firstcol;j<=lastcol;j++) {
       t1a[j] = 0.0;
     }
   }
   if (gp[procid].neighbors[LEFT] == -1) {
     for(j=firstrow;j<=lastrow;j++) {
       t2a[j][0] = 0.0;
     }
   }
   if (gp[procid].neighbors[RIGHT] == -1) {
     for(j=firstrow;j<=lastrow;j++) {
       t2a[j][jm-1] = 0.0;
     }
   }
   
   for(i=firstrow;i<=lastrow;i++) {
     t1a = (double *) t2a[i];
     for(iindex=firstcol;iindex<=lastcol;iindex++) {
       t1a[iindex] = 0.0;
     }
   }
   t2a = (double **) psilm[procid];
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     t2a[0][0]=0.0;
   }
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     t2a[im-1][0]=0.0;
   }
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     t2a[0][jm-1]=0.0;
   }
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     t2a[im-1][jm-1]=0.0;
   }
   if (gp[procid].neighbors[UP] == -1) {
     t1a = (double *) t2a[0];
     for(j=firstcol;j<=lastcol;j++) {
       t1a[j] = 0.0;
     }
   }
   if (gp[procid].neighbors[DOWN] == -1) {
     t1a = (double *) t2a[im-1];
     for(j=firstcol;j<=lastcol;j++) {
       t1a[j] = 0.0;
     }
   }
   if (gp[procid].neighbors[LEFT] == -1) {
     for(j=firstrow;j<=lastrow;j++) {
       t2a[j][0] = 0.0;
     }
   }
   if (gp[procid].neighbors[RIGHT] == -1) {
     for(j=firstrow;j<=lastrow;j++) {
       t2a[j][jm-1] = 0.0;
     }
   }
   for(i=firstrow;i<=lastrow;i++) {
     t1a = (double *) t2a[i];
     for(iindex=firstcol;iindex<=lastcol;iindex++) {
       t1a[iindex] = 0.0;
     }
   }

   t2a = (double **) psib[procid];
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     t2a[0][0]=1.0;
   }
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     t2a[0][jm-1]=1.0;
   }
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     t2a[im-1][0]=1.0;
   }
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     t2a[im-1][jm-1]=1.0;
   }
   if (gp[procid].neighbors[UP] == -1) {
     t1a = (double *) t2a[0];
     for(j=firstcol;j<=lastcol;j++) {
       t1a[j] = 1.0;
     }
   }
   if (gp[procid].neighbors[DOWN] == -1) {
     t1a = (double *) t2a[im-1];
     for(j=firstcol;j<=lastcol;j++) {
       t1a[j] = 1.0;
     }
   }
   if (gp[procid].neighbors[LEFT] == -1) {
     for(j=firstrow;j<=lastrow;j++) {
       t2a[j][0] = 1.0;
     }
   }
   if (gp[procid].neighbors[RIGHT] == -1) {
     for(j=firstrow;j<=lastrow;j++) {
       t2a[j][jm-1] = 1.0;
     }
   }
   for(i=firstrow;i<=lastrow;i++) {
     t1a = (double *) t2a[i];
     for(iindex=firstcol;iindex<=lastcol;iindex++) {
       t1a[iindex] = 0.0;
     }
   }

/* wait until all processes have completed the above initialization  */

   BARRIER(bars->sl_prini,nprocs)
 
/* compute psib array (one-time computation) and integrate into psibi */
 
   istart = 1;
   iend = istart + gp[procid].rel_num_y[numlev-1] - 1;
   jstart = 1;
   jend = jstart + gp[procid].rel_num_x[numlev-1] - 1;    
   ist = istart;
   ien = iend;
   jst = jstart;
   jen = jend;  
   
   if (gp[procid].neighbors[UP] == -1) {
     istart = 0;
   }
   if (gp[procid].neighbors[LEFT] == -1) {
     jstart = 0;
   }
   if (gp[procid].neighbors[DOWN] == -1) {
     iend = im-1;   
   }
   if (gp[procid].neighbors[RIGHT] == -1) {
     jend = jm-1;    
   }

   t2a = (double **) rhs_multi[procid][numlev-1];
   t2b = (double **) psib[procid];
   for(i=istart;i<=iend;i++) {
     t1a = (double *) t2a[i];
     t1b = (double *) t2b[i];
     for(j=jstart;j<=jend;j++) {
       t1a[j] = t1b[j] * ressqr;
     }
   }  
   t2a = (double **) q_multi[procid][numlev-1];
   if (gp[procid].neighbors[UP] == -1) {
     t1a = (double *) t2a[0];
     t1b = (double *) t2b[0];
     for(j=jstart;j<=jend;j++) {
       t1a[j] = t1b[j];
     }
   }
   if (gp[procid].neighbors[DOWN] == -1) {
     t1a = (double *) t2a[im-1];
     t1b = (double *) t2b[im-1];
     for(j=jstart;j<=jend;j++) {
       t1a[j] = t1b[j];
     }
   }
   if (gp[procid].neighbors[LEFT] == -1) {
     for(i=istart;i<=iend;i++) {
       t2a[i][0] = t2b[i][0];
     }
   }
   if (gp[procid].neighbors[RIGHT] == -1) {
     for(i=istart;i<=iend;i++) {
       t2a[i][jm-1] = t2b[i][jm-1];
     }
   }
   
   BARRIER(bars->sl_psini,nprocs) 

   t2a = (double **) psib[procid];
   j = gp[procid].neighbors[UP];
   if (j != -1) {
     t1a = (double *) t2a[0];
     t1b = (double *) psib[j][im-2];
     for (i=1;i<jm-1;i++) {
       t1a[i] = t1b[i];
     }
   }
   j = gp[procid].neighbors[DOWN];
   if (j != -1) {
     t1a = (double *) t2a[im-1];
     t1b = (double *) psib[j][1];
     for (i=1;i<jm-1;i++) {
       t1a[i] = t1b[i];
     }
   }
   j = gp[procid].neighbors[LEFT];
   if (j != -1) {
     t2b = (double **) psib[j];
     for (i=1;i<im-1;i++) {
       t2a[i][0] = t2b[i][jm-2];
     }
   }
   j = gp[procid].neighbors[RIGHT];
   if (j != -1) {
     t2b = (double **) psib[j];
     for (i=1;i<im-1;i++) {
       t2a[i][jm-1] = t2b[i][1];
     }
   }  

   t2a = (double **) q_multi[procid][numlev-1];
   t2b = (double **) psib[procid];
   fac = 1.0 / (4.0 - ressqr*eig2);
   for(i=ist;i<=ien;i++) {
     t1a = (double *) t2a[i];
     t1b = (double *) t2b[i];
     t1c = (double *) t2b[i-1];
     t1d = (double *) t2b[i+1];
     for(j=jst;j<=jen;j++) {
       t1a[j] = fac * (t1d[j]+t1c[j]+t1b[j+1]+t1b[j-1] - 
                   ressqr*t1b[j]);
     }
   }
   
   multig(procid);

   for(i=istart;i<=iend;i++) {
     t1a = (double *) t2a[i];
     t1b = (double *) t2b[i];
     for(j=jstart;j<=jend;j++) {
       t1b[j] = t1a[j];
     }
   }

   BARRIER(bars->sl_prini,nprocs)

/* update the local running sum psibipriv by summing all the resulting
   values in that process's share of the psib matrix   */

   t2a = (double **) psib[procid];
   psibipriv=0.0;
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     psibipriv = psibipriv + 0.25*(t2a[0][0]);
   }
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     psibipriv = psibipriv + 0.25*(t2a[0][jm-1]);
   }
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     psibipriv=psibipriv+0.25*(t2a[im-1][0]);
   }
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     psibipriv=psibipriv+0.25*(t2a[im-1][jm-1]);
   }
   if (gp[procid].neighbors[UP] == -1) {
     t1a = (double *) t2a[0];
     for(j=firstcol;j<=lastcol;j++) {
       psibipriv = psibipriv + 0.5*t1a[j];
     }
   }
   if (gp[procid].neighbors[DOWN] == -1) {
     t1a = (double *) t2a[im-1];
     for(j=firstcol;j<=lastcol;j++) {
       psibipriv = psibipriv + 0.5*t1a[j];
     }
   }
   if (gp[procid].neighbors[LEFT] == -1) {
     for(j=firstrow;j<=lastrow;j++) {
       psibipriv = psibipriv + 0.5*t2a[j][0];
     }
   }
   if (gp[procid].neighbors[RIGHT] == -1) {
     for(j=firstrow;j<=lastrow;j++) {
       psibipriv = psibipriv + 0.5*t2a[j][jm-1];
     }
   }
   for(i=firstrow;i<=lastrow;i++) {
     t1a = (double *) t2a[i];
     for(iindex=firstcol;iindex<=lastcol;iindex++) {
       psibipriv = psibipriv + t1a[iindex];
     }
   } 

/* update the shared variable psibi by summing all the psibiprivs
   of the individual processes into it.  note that this combined
   private and shared sum method avoids accessing the shared 
   variable psibi once for every element of the matrix.  */

   LOCK(locks->psibilock)
     global->psibi = global->psibi + psibipriv;
   UNLOCK(locks->psibilock)

/* initialize psim matrices
   
   if there is more than one process, then split the processes
   between the two psim matrices; otherwise, let the single process
   work on one first and then the other   */

   for(psiindex=0;psiindex<=1;psiindex++) {
     t2a = (double **) psim[procid][psiindex];
     if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
       t2a[0][0] = 0.0;
     }
     if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
       t2a[im-1][0] = 0.0;
     }
     if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
       t2a[0][jm-1] = 0.0;
     }
     if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {
       t2a[im-1][jm-1] = 0.0;
     }
     if (gp[procid].neighbors[UP] == -1) {
       t1a = (double *) t2a[0];
       for(j=firstcol;j<=lastcol;j++) {
         t1a[j] = 0.0;
       }
     }
     if (gp[procid].neighbors[DOWN] == -1) {
       t1a = (double *) t2a[im-1];
       for(j=firstcol;j<=lastcol;j++) {
         t1a[j] = 0.0;
       }
     }
     if (gp[procid].neighbors[LEFT] == -1) {
       for(j=firstrow;j<=lastrow;j++) {
         t2a[j][0] = 0.0;
       }
     }
     if (gp[procid].neighbors[RIGHT] == -1) {
       for(j=firstrow;j<=lastrow;j++) {
         t2a[j][jm-1] = 0.0;
       }
     }
     for(i=firstrow;i<=lastrow;i++) {
       t1a = (double *) t2a[i];
       for(iindex=firstcol;iindex<=lastcol;iindex++) {
         t1a[iindex] = 0.0;
       }
     }
   }
 
/* initialize psi matrices the same way  */

   for(psiindex=0;psiindex<=1;psiindex++) {
     t2a = (double **) psi[procid][psiindex];
     if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
       t2a[0][0] = 0.0;
     }
     if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
       t2a[0][jm-1] = 0.0;
     }
     if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
       t2a[im-1][0] = 0.0;
     }
     if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {
       t2a[im-1][jm-1] = 0.0;
     }
     if (gp[procid].neighbors[UP] == -1) {
       t1a = (double *) t2a[0];
       for(j=firstcol;j<=lastcol;j++) {
         t1a[j] = 0.0;
       }
     }
     if (gp[procid].neighbors[DOWN] == -1) {
       t1a = (double *) t2a[im-1];
       for(j=firstcol;j<=lastcol;j++) {
         t1a[j] = 0.0;
       }
     }
     if (gp[procid].neighbors[LEFT] == -1) {
       for(j=firstrow;j<=lastrow;j++) {
         t2a[j][0] = 0.0;
       }
     }
     if (gp[procid].neighbors[RIGHT] == -1) {
       for(j=firstrow;j<=lastrow;j++) {
         t2a[j][jm-1] = 0.0;
       }
     }
     for(i=firstrow;i<=lastrow;i++) {
       t1a = (double *) t2a[i];
       for(iindex=firstcol;iindex<=lastcol;iindex++) {
         t1a[iindex] = 0.0;
       }
     }
   }

/* compute input curl of wind stress */

   t2a = (double **) tauz[procid];
   ysca1 = .5*ysca;
   factor= -t0*pi/ysca1;
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     t2a[0][0] = 0.0;
   }
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
     t2a[im-1][0] = 0.0;
   }
   if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     sintemp = pi*((double) jm-1+j_off)*res/ysca1;
     sintemp = sin(sintemp);
     t2a[0][jm-1] = factor*sintemp;
   }
   if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
     sintemp = pi*((double) jm-1+j_off)*res/ysca1;
     sintemp = sin(sintemp);
     t2a[im-1][jm-1] = factor*sintemp;
   }
   if (gp[procid].neighbors[UP] == -1) {
     t1a = (double *) t2a[0];
     for(j=firstcol;j<=lastcol;j++) {
       sintemp = pi*((double) j+j_off)*res/ysca1;
       sintemp = sin(sintemp);
       curlt = factor*sintemp;
       t1a[j] = curlt;
     }
   }
   if (gp[procid].neighbors[DOWN] == -1) {
     t1a = (double *) t2a[im-1];
     for(j=firstcol;j<=lastcol;j++) {
       sintemp = pi*((double) j+j_off)*res/ysca1;
       sintemp = sin(sintemp);
       curlt = factor*sintemp;
       t1a[j] = curlt;
     }
   }
   if (gp[procid].neighbors[LEFT] == -1) {
     for(j=firstrow;j<=lastrow;j++) {
       t2a[j][0] = 0.0;
     }
   }
   if (gp[procid].neighbors[RIGHT] == -1) {
     sintemp = pi*((double) jm-1+j_off)*res/ysca1;
     sintemp = sin(sintemp);
     curlt = factor*sintemp;
     for(j=firstrow;j<=lastrow;j++) {
       t2a[j][jm-1] = curlt;
     }
   }
   for(i=firstrow;i<=lastrow;i++) {
     t1a = (double *) t2a[i];
     for(iindex=firstcol;iindex<=lastcol;iindex++) {
       sintemp = pi*((double) iindex+j_off)*res/ysca1;
       sintemp = sin(sintemp);
       curlt = factor*sintemp;
       t1a[iindex] = curlt;
     }
   }  
   
   BARRIER(bars->sl_onetime,nprocs)
   
   
/***************************************************************
 one-time stuff over at this point
 ***************************************************************/

   while (!endflag) {
     while ((!dayflag) || (!dhourflag)) {
       dayflag = 0;
       dhourflag = 0;
       if (nstep == 1) {
         if (procid == MASTER) {
            CLOCK(global->trackstart)
         }
	 if ((procid == MASTER) || (do_stats)) {
	   CLOCK(t1);
           gp[procid].total_time = t1;
           gp[procid].multi_time = 0;
	 }
/* POSSIBLE ENHANCEMENT:  Here is where one might reset the
   statistics that one is measuring about the parallel execution */
       }

       slave2(procid,firstrow,lastrow,numrows,firstcol,lastcol,numcols);

/* update time and step number
   note that these time and step variables are private i.e. every
   process has its own copy and keeps track of its own time  */

       ttime = ttime + dtau;
       nstep = nstep + 1;
       day = ttime/86400.0;
 
       if (day > ((double) outday0)) {
         dayflag = 1;
         iday = (int) day;
         dhour = dhour+dtau;
         if (dhour >= 86400.0) {
	   dhourflag = 1;
         }
       }
     }
     dhour = 0.0;

     t2a = (double **) psium[procid];
     t2b = (double **) psim[procid][0];
     if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
       t2a[0][0] = t2a[0][0]+t2b[0][0];
     }
     if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
       t2a[im-1][0] = t2a[im-1][0]+t2b[im-1][0];
     }
     if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
       t2a[0][jm-1] = t2a[0][jm-1]+t2b[0][jm-1];
     }
     if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {
       t2a[im-1][jm-1] = t2a[im-1][jm-1] +
				   t2b[im-1][jm-1];
     }
     if (gp[procid].neighbors[UP] == -1) {
       t1a = (double *) t2a[0];
       t1b = (double *) t2b[0];
       for(j=firstcol;j<=lastcol;j++) {
         t1a[j] = t1a[j]+t1b[j];
       }
     }
     if (gp[procid].neighbors[DOWN] == -1) {
       t1a = (double *) t2a[im-1];
       t1b = (double *) t2b[im-1];
       for(j=firstcol;j<=lastcol;j++) {
         t1a[j] = t1a[j] + t1b[j];
       }
     }
     if (gp[procid].neighbors[LEFT] == -1) {
       for(j=firstrow;j<=lastrow;j++) {
         t2a[j][0] = t2a[j][0]+t2b[j][0];
       }
     }
     if (gp[procid].neighbors[RIGHT] == -1) {
       for(j=firstrow;j<=lastrow;j++) {
         t2a[j][jm-1] = t2a[j][jm-1] +
				  t2b[j][jm-1];
       }
     }
     for(i=firstrow;i<=lastrow;i++) {
       t1a = (double *) t2a[i];
       t1b = (double *) t2b[i];
       for(iindex=firstcol;iindex<=lastcol;iindex++) {
         t1a[iindex] = t1a[iindex] + t1b[iindex];
       }
     }
     
/* update values of psilm array to psilm + psim[2]  */
     
     t2a = (double **) psilm[procid];
     t2b = (double **) psim[procid][1];
     if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
       t2a[0][0] = t2a[0][0]+t2b[0][0];
     }
     if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[LEFT] == -1)) {  
       t2a[im-1][0] = t2a[im-1][0]+t2b[im-1][0];
     }
     if ((gp[procid].neighbors[UP] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {  
       t2a[0][jm-1] = t2a[0][jm-1]+t2b[0][jm-1];
     }
     if ((gp[procid].neighbors[DOWN] == -1) && (gp[procid].neighbors[RIGHT] == -1)) {
       t2a[im-1][jm-1] = t2a[im-1][jm-1] +
				   t2b[im-1][jm-1];
     }
     if (gp[procid].neighbors[UP] == -1) {
       t1a = (double *) t2a[0];
       t1b = (double *) t2b[0];
       for(j=firstcol;j<=lastcol;j++) {
         t1a[j] = t1a[j]+t1b[j];
       }
     }
     if (gp[procid].neighbors[DOWN] == -1) {
       t1a = (double *) t2a[im-1];
       t1b = (double *) t2b[im-1];
       for(j=firstcol;j<=lastcol;j++) {
         t1a[j] = t1a[j]+t1b[j];
       }
     }
     if (gp[procid].neighbors[LEFT] == -1) {
       for(j=firstrow;j<=lastrow;j++) {
         t2a[j][0] = t2a[j][0]+t2b[j][0];
       }
     }
     if (gp[procid].neighbors[RIGHT] == -1) {
       for(j=firstrow;j<=lastrow;j++) {
         t2a[j][jm-1] = t2a[j][jm-1] + t2b[j][jm-1];
       }
     }
     for(i=firstrow;i<=lastrow;i++) {
       t1a = (double *) t2a[i];
       t1b = (double *) t2b[i];
       for(iindex=firstcol;iindex<=lastcol;iindex++) {
         t1a[iindex] = t1a[iindex] + t1b[iindex];
       }
     }
     if (iday >= (int) outday3) {
       endflag = 1;
     }
  }
  if ((procid == MASTER) || (do_stats)) {
    CLOCK(t1);
    gp[procid].total_time = t1-gp[procid].total_time;
  }
}