2:  #include <petscmat.h>
  3:  #include <petsc/private/petscimpl.h>

  5: /*
  6:      MatDumpSPAI - Dumps a PETSc matrix to a file in an ASCII format
  7:   suitable for the SPAI code of Stephen Barnard to solve. This routine
  8:   is simply here to allow testing of matrices directly with the SPAI
  9:   code, rather then through the PETSc interface.

 11: */
 12: PetscErrorCode  MatDumpSPAI(Mat A,FILE *file)
 13: {
 14:   const PetscScalar *vals;
 15:   PetscErrorCode    ierr;
 16:   int               i,j,n,size,nz;
 17:   const int         *cols;
 18:   MPI_Comm          comm;

 20:   PetscObjectGetComm((PetscObject)A,&comm);

 22:   MPI_Comm_size(comm,&size);
 23:   if (size > 1) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"Only single processor dumps");

 25:   MatGetSize(A,&n,&n);

 27:   /* print the matrix */
 28:   fprintf(file,"%d\n",n);
 29:   for (i=0; i<n; i++) {
 30:     MatGetRow(A,i,&nz,&cols,&vals);
 31:     for (j=0; j<nz; j++) fprintf(file,"%d %d %16.14e\n",i+1,cols[j]+1,vals[j]);
 32:     MatRestoreRow(A,i,&nz,&cols,&vals);
 33:   }
 34:   return(0);
 35: }

 37: PetscErrorCode  VecDumpSPAI(Vec b,FILE *file)
 38: {
 40:   int            n,i;
 41:   PetscScalar    *array;

 43:   VecGetSize(b,&n);
 44:   VecGetArray(b,&array);

 46:   fprintf(file,"%d\n",n);
 47:   for (i=0; i<n; i++) fprintf(file,"%d %16.14e\n",i+1,array[i]);
 48:   return(0);
 49: }