static PetscErrorCode PCSetUp_SPAI(PC pc)
{
PC_SPAI *ispai = (PC_SPAI*)pc->data;
PetscErrorCode ierr;
Mat AT;
PetscFunctionBegin;
init_SPAI();
if (ispai->sp) {
ierr = ConvertMatToMatrix(ispai->comm_spai,pc->pmat,pc->pmat,&ispai->B);CHKERRQ(ierr);
} else {
/* Use the transpose to get the column nonzero structure. */
ierr = MatTranspose(pc->pmat,MAT_INITIAL_MATRIX,&AT);CHKERRQ(ierr);
ierr = ConvertMatToMatrix(ispai->comm_spai,pc->pmat,AT,&ispai->B);CHKERRQ(ierr);
ierr = MatDestroy(&AT);CHKERRQ(ierr);
}
/* Destroy the transpose */
/* Don't know how to do it. PETSc developers? */
/* construct SPAI preconditioner */
/* FILE *messages */ /* file for warning messages */
/* double epsilon */ /* tolerance */
/* int nbsteps */ /* max number of "improvement" steps per line */
/* int max */ /* max dimensions of is_I, q, etc. */
/* int maxnew */ /* max number of new entries per step */
/* int block_size */ /* block_size == 1 specifies scalar elments
block_size == n specifies nxn constant-block elements
block_size == 0 specifies variable-block elements */
/* int cache_size */ /* one of (1,2,3,4,5,6) indicting size of cache */
/* cache_size == 0 indicates no caching */
/* int verbose */ /* verbose == 0 specifies that SPAI is silent
verbose == 1 prints timing and matrix statistics */
ierr = bspai(ispai->B,&ispai->M,
stdout,
ispai->epsilon,
ispai->nbsteps,
ispai->max,
ispai->maxnew,
ispai->block_size,
ispai->cache_size,
ispai->verbose);CHKERRQ(ierr);
ierr = ConvertMatrixToMat(((PetscObject)pc)->comm,ispai->M,&ispai->PM);CHKERRQ(ierr);
/* free the SPAI matrices */
sp_free_matrix(ispai->B);
sp_free_matrix(ispai->M);
PetscFunctionReturn(0);
}
int bspai
(matrix *A, matrix **bspai_matrix,
FILE *messages_arg, /* file for warning messages */
double epsilon_arg, /* tolerance */
int nbsteps_arg, /* max number of accepted elements per line
(sc = 0); is set to ld+lu+1 for spar = 2 */
int max_arg, /* max dimensions of I, q, etc. */
int maxnew_arg, /* max number of new entries per step */
int bs, /* block size */
int cache_size_arg, /* one of (1,2,3,4,5,6) indicting size of cache */
/* cache_size == 0 indicates no caching */
int verbose_arg,
int spar_arg,
int lower_diag_arg,
int upper_diag_arg,
double tau_arg)
{
matrix *B;
matrix *M_B;
matrix *M;
extern int A_max_block_size;
int total_bad_cols;
int j,nnz,ierr;
if (verbose_arg) matrix_statistics(A,"A");
if (spar_arg && A->max_block_size > 1) /* MH: ??? */
{
printf("Sorry, sc > 0 only supported for block size 1\n");
exit(1);
}
/* Scalar case */
if (bs == 1) {
if (verbose_arg && (A->myid == 0))
printf("\nConstructing scalar SPAI matrix M from A\n");
if ((ierr = spai(A, &M,
messages_arg,
epsilon_arg,
nbsteps_arg,
max_arg,
maxnew_arg,
cache_size_arg,
verbose_arg,
spar_arg,
lower_diag_arg,
upper_diag_arg,
tau_arg)) != 0) return ierr;
#ifdef MPI
MPI_Barrier(A->comm);
#endif
}
/* Block case */
else {
/* Convert A to either a constant or variable block matrix B. */
/* The 3rd argument can be used to set an upper limit
on the block size. For now it's unused (i.e., zero). */
if (verbose_arg && (A->myid == 0))
printf("\nConstructing block matrix B from A\n");
B = block_matrix(A,bs,0,verbose_arg);
if (verbose_arg) matrix_statistics(B,"B");
if (verbose_arg && (A->myid == 0))
printf("Constructing block SPAI matrix M_B from B\n");
if ((ierr = spai(B, &M_B,
messages_arg,
epsilon_arg,
nbsteps_arg,
max_arg,
maxnew_arg,
cache_size_arg,
verbose_arg,
spar_arg,
lower_diag_arg,
upper_diag_arg,
tau_arg)) != 0) return ierr;
#ifdef MPI
MPI_Barrier(A->comm);
#endif
/* VE */
if (num_bad_cols) printf("SPAI: # bad columns = %d\n",num_bad_cols);
if (verbose_arg) matrix_statistics(M_B,"M_B");
/* Convert M_B to scalar matrix. */
if (verbose_arg && (A->myid == 0))
printf("\nConstructing scalar SPAI matrix M from M_B\n");
M = scalar_matrix(M_B,verbose_arg);
sp_free_matrix(B);
sp_free_matrix(M_B);
}
if (verbose_arg) matrix_statistics(M,"M");
*bspai_matrix = M;
return 0;
}
