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. Writesn
  4: them using the PETSc sparse format. Input parameters are:n
  5:   -fin <filename> : input filen
  6:   -fout <filename> : output filenn";

 8:  #include petscmat.h

 10: int main(int argc,char **args)
 11: {
 12:   Mat         A;
 13:   Vec         b;
 14:   char        filein[128],fileout[128];
 15:   int         i,j,m,n,nnz,ierr,rank,size,start,end,*col,*row,*brow,length;
 16:   PetscScalar *val,*bval;
 17:   FILE*       file;
 18:   PetscViewer view;

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

 22:   /* Read in matrix and RHS */
 23:   PetscOptionsGetString(PETSC_NULL,"-fin",filein,127,PETSC_NULL);
 24:   MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
 25:   MPI_Comm_size(PETSC_COMM_WORLD,&size);

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

 29:   fscanf(file,"  NUNKNS =%d  NCOEFF =%dn",&n,&nnz);
 30:   fscanf(file,"  JA POINTER IN SLAPSVn");

 32:   MatCreateSeqAIJ(PETSC_COMM_WORLD,n,n,20,0,&A);
 33:   VecCreate(PETSC_COMM_WORLD,&b);
 34:   VecSetSizes(b,PETSC_DECIDE,n);
 35:   VecSetFromOptions(b);

 37:   PetscMalloc((n+1)*sizeof(int),&col);
 38:   for (i=0; i<n+1; i++)
 39:     fscanf(file,"     I=%d%dn",&j,&col[i]);
 40:   fscanf(file,"  EOD JAn");

 42:   PetscMalloc(nnz*sizeof(PetscScalar),&val);
 43:   PetscMalloc(nnz*sizeof(int),&row);
 44:   fscanf(file,"  COEFFICIENT MATRIX IN SLAPSV: I, IA, An");
 45:   for (i=0; i<nnz; i++) {
 46:     fscanf(file,"    %d%d%len",&j,&row[i],&val[i]);
 47:     row[i]--;
 48:   }
 49:   fscanf(file,"  EOD IAn");

 51:   PetscMalloc(n*sizeof(PetscScalar),&bval);
 52:   PetscMalloc(n*sizeof(int),&brow);
 53:   fscanf(file,"  RESIDUAL IN SLAPSV ;IRHS=%dn",&j);
 54:   for (i=0; i<n; i++) {
 55:     fscanf(file,"      %d%le%dn",&j,bval+i,&j);
 56:     brow[i] = i;
 57:   }
 58:   fscanf(file,"  EOD RESIDUAL");
 59:   fclose(file);

 61:   m = n/size+1;
 62:   start = rank*m;
 63:   end = (rank+1)*m; if (end > n) end = n;
 64:   for (j=start; j<end; j++) {
 65:     length = col[j+1]-col[j];
 66:     MatSetValues(A,length,&row[col[j]-1],1,&j,&val[col[j]-1],INSERT_VALUES);
 67:   }
 68:   MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
 69:   MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);

 71:   VecGetOwnershipRange(b,&start,&end);
 72:   VecSetValues(b,end-start,brow+start,bval+start,INSERT_VALUES);
 73:   VecAssemblyBegin(b);
 74:   VecAssemblyEnd(b);

 76:   PetscFree(col);
 77:   PetscFree(val);
 78:   PetscFree(row);
 79:   PetscFree(bval);
 80:   PetscFree(brow);

 82:   PetscPrintf(PETSC_COMM_SELF,"Reading matrix completes.n");
 83:   PetscOptionsGetString(PETSC_NULL,"-fout",fileout,127,PETSC_NULL);
 84:   PetscViewerBinaryOpen(PETSC_COMM_WORLD,fileout,PETSC_BINARY_CREATE,&view);
 85:   MatView(A,view);
 86:   VecView(b,view);
 87:   PetscViewerDestroy(view);

 89:   VecDestroy(b);
 90:   MatDestroy(A);

 92:   PetscFinalize();
 93:   return 0;
 94: }