Actual source code: ex32.c

  1: /*$Id: ex32.c,v 1.30 2001/09/11 16:32:50 bsmith Exp $*/

  3: static char help[] = "Reads in a matrix and vector in ASCII slap format. Writes\n\
  4: them using the PETSc sparse format. Input parameters are:\n\
  5:   -fin <filename> : input file\n\
  6:   -fout <filename> : output file\n\n";

 8:  #include petscmat.h

 12: int main(int argc,char **args)
 13: {
 14:   Mat         A;
 15:   Vec         b;
 16:   char        filein[128],fileout[128];
 17:   int         i,j,m,n,nnz,ierr,rank,size,start,end,*col,*row,*brow,length;
 18:   PetscScalar *val,*bval;
 19:   FILE*       file;
 20:   PetscViewer view;
 21:   PetscTruth  opt;

 23:   PetscInitialize(&argc,&args,(char *)0,help);

 25:   /* Read in matrix and RHS */
 26:   PetscOptionsGetString(PETSC_NULL,"-fin",filein,127,&opt);
 27:   if (opt == PETSC_FALSE) {
 28:     SETERRQ(PETSC_ERR_ARG_WRONG, "No filename was specified for this test");
 29:   }
 30:   MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
 31:   MPI_Comm_size(PETSC_COMM_WORLD,&size);

 33:   PetscFOpen(PETSC_COMM_SELF,filein,"r",&file);

 35:   fscanf(file,"  NUNKNS =%d  NCOEFF =%d\n",&n,&nnz);
 36:   fscanf(file,"  JA POINTER IN SLAPSV\n");

 38:   MatCreateSeqAIJ(PETSC_COMM_WORLD,n,n,20,0,&A);
 39:   VecCreate(PETSC_COMM_WORLD,&b);
 40:   VecSetSizes(b,PETSC_DECIDE,n);
 41:   VecSetFromOptions(b);

 43:   PetscMalloc((n+1)*sizeof(int),&col);
 44:   for (i=0; i<n+1; i++)
 45:     fscanf(file,"     I=%d%d\n",&j,&col[i]);
 46:   fscanf(file,"  EOD JA\n");

 48:   PetscMalloc(nnz*sizeof(PetscScalar),&val);
 49:   PetscMalloc(nnz*sizeof(int),&row);
 50:   fscanf(file,"  COEFFICIENT MATRIX IN SLAPSV: I, IA, A\n");
 51:   for (i=0; i<nnz; i++) {
 52:     fscanf(file,"    %d%d%le\n",&j,&row[i],&val[i]);
 53:     row[i]--;
 54:   }
 55:   fscanf(file,"  EOD IA\n");

 57:   PetscMalloc(n*sizeof(PetscScalar),&bval);
 58:   PetscMalloc(n*sizeof(int),&brow);
 59:   fscanf(file,"  RESIDUAL IN SLAPSV ;IRHS=%d\n",&j);
 60:   for (i=0; i<n; i++) {
 61:     fscanf(file,"      %d%le%d\n",&j,bval+i,&j);
 62:     brow[i] = i;
 63:   }
 64:   fscanf(file,"  EOD RESIDUAL");
 65:   fclose(file);

 67:   m = n/size+1;
 68:   start = rank*m;
 69:   end = (rank+1)*m; if (end > n) end = n;
 70:   for (j=start; j<end; j++) {
 71:     length = col[j+1]-col[j];
 72:     MatSetValues(A,length,&row[col[j]-1],1,&j,&val[col[j]-1],INSERT_VALUES);
 73:   }
 74:   MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
 75:   MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);

 77:   VecGetOwnershipRange(b,&start,&end);
 78:   VecSetValues(b,end-start,brow+start,bval+start,INSERT_VALUES);
 79:   VecAssemblyBegin(b);
 80:   VecAssemblyEnd(b);

 82:   PetscFree(col);
 83:   PetscFree(val);
 84:   PetscFree(row);
 85:   PetscFree(bval);
 86:   PetscFree(brow);

 88:   PetscPrintf(PETSC_COMM_SELF,"Reading matrix completes.\n");
 89:   PetscOptionsGetString(PETSC_NULL,"-fout",fileout,127,PETSC_NULL);
 90:   PetscViewerBinaryOpen(PETSC_COMM_WORLD,fileout,PETSC_FILE_CREATE,&view);
 91:   MatView(A,view);
 92:   VecView(b,view);
 93:   PetscViewerDestroy(view);

 95:   VecDestroy(b);
 96:   MatDestroy(A);

 98:   PetscFinalize();
 99:   return 0;
100: }