Date: 2022-08-02T03:14:33+00:00

Actual source code: dspai.c

      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:   int               i,j,n,size,nz;
     16:   const int         *cols;
     17:   MPI_Comm          comm;

     19:   PetscObjectGetComm((PetscObject)A,&comm);
     20:   MPI_Comm_size(comm,&size);
     22:   MatGetSize(A,&n,&n);
     23:   /* print the matrix */
     24:   fprintf(file,"%d\n",n);
     25:   for (i=0; i<n; i++) {
     26:     MatGetRow(A,i,&nz,&cols,&vals);
     27:     for (j=0; j<nz; j++) fprintf(file,"%d %d %16.14e\n",i+1,cols[j]+1,vals[j]);
     28:     MatRestoreRow(A,i,&nz,&cols,&vals);
     29:   }
     30:   return 0;
     31: }

     33: PetscErrorCode  VecDumpSPAI(Vec b,FILE *file)
     34: {
     35:   int          n,i;
     36:   PetscScalar *array;

     38:   VecGetSize(b,&n);
     39:   VecGetArray(b,&array);
     40:   fprintf(file,"%d\n",n);
     41:   for (i=0; i<n; i++) fprintf(file,"%d %16.14e\n",i+1,array[i]);
     42:   return 0;
     43: }