| /*************************************************************************/ |
| /* */ |
| /* 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. */ |
| /* */ |
| /*************************************************************************/ |
| |
| /* Performs the laplacian calculation for a subblock */ |
| |
| EXTERN_ENV |
| |
| #include <stdio.h> |
| #include <math.h> |
| #include <time.h> |
| #include "decs.h" |
| |
| void laplacalc(procid,x,z,psiindex,firstrow,lastrow,firstcol,lastcol) |
| |
| int procid; |
| double ****x; |
| double ****z; |
| int psiindex; |
| int firstrow; |
| int lastrow; |
| int firstcol; |
| int lastcol; |
| |
| { |
| int iindex; |
| int indexp1; |
| int indexm1; |
| int ip1; |
| int im1; |
| int i; |
| int j; |
| double **t2a; |
| double **t2b; |
| double *t1a; |
| double *t1b; |
| double *t1c; |
| double *t1d; |
| |
| t2a = (double **) x[procid][psiindex]; |
| j = gp[procid].neighbors[UP]; |
| if (j != -1) { |
| t1a = (double *) t2a[0]; |
| t1b = (double *) x[j][psiindex][im-2]; |
| for (i=1;i<=lastcol;i++) { |
| t1a[i] = t1b[i]; |
| } |
| } |
| j = gp[procid].neighbors[DOWN]; |
| if (j != -1) { |
| t1a = (double *) t2a[im-1]; |
| t1b = (double *) x[j][psiindex][1]; |
| for (i=1;i<=lastcol;i++) { |
| t1a[i] = t1b[i]; |
| } |
| } |
| j = gp[procid].neighbors[LEFT]; |
| if (j != -1) { |
| t2b = (double **) x[j][psiindex]; |
| for (i=1;i<=lastrow;i++) { |
| t2a[i][0] = t2b[i][jm-2]; |
| } |
| } |
| j = gp[procid].neighbors[RIGHT]; |
| if (j != -1) { |
| t2b = (double **) x[j][psiindex]; |
| for (i=1;i<=lastrow;i++) { |
| t2a[i][jm-1] = t2b[i][1]; |
| } |
| } |
| |
| t2a = (double **) x[procid][psiindex]; |
| t2b = (double **) z[procid][psiindex]; |
| for (i=firstrow;i<=lastrow;i++) { |
| ip1 = i+1; |
| im1 = i-1; |
| t1a = (double *) t2a[i]; |
| t1b = (double *) t2b[i]; |
| t1c = (double *) t2a[ip1]; |
| t1d = (double *) t2a[im1]; |
| for (iindex=firstcol;iindex<=lastcol;iindex++) { |
| indexp1 = iindex+1; |
| indexm1 = iindex-1; |
| t1b[iindex] = factlap*(t1c[iindex]+ |
| t1d[iindex]+t1a[indexp1]+ |
| t1a[indexm1]-4.*t1a[iindex]); |
| } |
| } |
| |
| if (gp[procid].neighbors[UP] == -1) { |
| t1b = (double *) t2b[0]; |
| for (j=firstcol;j<=lastcol;j++) { |
| t1b[j] = 0.0; |
| } |
| } |
| if (gp[procid].neighbors[DOWN] == -1) { |
| t1b = (double *) t2b[im-1]; |
| for (j=firstcol;j<=lastcol;j++) { |
| t1b[j] = 0.0; |
| } |
| } |
| if (gp[procid].neighbors[LEFT] == -1) { |
| for (j=firstrow;j<=lastrow;j++) { |
| t2b[j][0] = 0.0; |
| } |
| } |
| if (gp[procid].neighbors[RIGHT] == -1) { |
| for (j=firstrow;j<=lastrow;j++) { |
| t2b[j][jm-1] = 0.0; |
| } |
| } |
| |
| } |