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: #undef __FUNCT__
 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;

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

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

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

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

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

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

 44:   PetscMalloc(nnz*sizeof(PetscScalar),&val);
 45:   PetscMalloc(nnz*sizeof(int),&row);
 46:   fscanf(file,"  COEFFICIENT MATRIX IN SLAPSV: I, IA, An");
 47:   for (i=0; i<nnz; i++) {
 48:     fscanf(file,"    %d%d%len",&j,&row[i],&val[i]);
 49:     row[i]--;
 50:   }
 51:   fscanf(file,"  EOD IAn");

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

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

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

 78:   PetscFree(col);
 79:   PetscFree(val);
 80:   PetscFree(row);
 81:   PetscFree(bval);
 82:   PetscFree(brow);

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

 91:   VecDestroy(b);
 92:   MatDestroy(A);

 94:   PetscFinalize();
 95:   return 0;
 96: }