Multilevel Multilevel_new(SparseMatrix A0, real *node_weights, Multilevel_control ctrl){
Multilevel grid;
SparseMatrix A = A0;
if (!SparseMatrix_is_symmetric(A, FALSE) || A->type != MATRIX_TYPE_REAL){
A = SparseMatrix_get_real_adjacency_matrix_symmetrized(A);
}
grid = Multilevel_init(A, node_weights);
grid = Multilevel_establish(grid, ctrl);
if (A != A0) grid->delete_top_level_A = TRUE;/* be sure to clean up later */
return grid;
}
Multilevel Multilevel_new(SparseMatrix A0, SparseMatrix D0, real *node_weights, Multilevel_control ctrl){
/* A: the weighting matrix. D: the distance matrix, could be NULL. If not null, the two matrices must have the same sparsity pattern */
Multilevel grid;
SparseMatrix A = A0, D = D0;
if (!SparseMatrix_is_symmetric(A, FALSE) || A->type != MATRIX_TYPE_REAL){
A = SparseMatrix_get_real_adjacency_matrix_symmetrized(A);
}
if (D && (!SparseMatrix_is_symmetric(D, FALSE) || D->type != MATRIX_TYPE_REAL)){
D = SparseMatrix_symmetrize_nodiag(D, FALSE);
}
grid = Multilevel_init(A, D, node_weights);
grid = Multilevel_establish(grid, ctrl);
if (A != A0) grid->delete_top_level_A = TRUE;/* be sure to clean up later */
return grid;
}
static Multilevel Multilevel_establish(Multilevel grid, Multilevel_control ctrl){
Multilevel cgrid;
int coarsen_scheme_used;
real *cnode_weights = NULL;
SparseMatrix P, R, A, cA, D, cD;
#ifdef DEBUG_PRINT
if (Verbose) {
print_padding(grid->level);
fprintf(stderr, "level -- %d, n = %d, nz = %d nz/n = %f\n", grid->level, grid->n, grid->A->nz, grid->A->nz/(double) grid->n);
}
#endif
A = grid->A;
D = grid->D;
if (grid->level >= ctrl->maxlevel - 1) {
#ifdef DEBUG_PRINT
if (Verbose) {
print_padding(grid->level);
fprintf(stderr, " maxlevel reached, coarsening stops\n");
}
#endif
return grid;
}
Multilevel_coarsen(A, &cA, D, &cD, grid->node_weights, &cnode_weights, &P, &R, ctrl, &coarsen_scheme_used);
if (!cA) return grid;
cgrid = Multilevel_init(cA, cD, cnode_weights);
grid->next = cgrid;
cgrid->coarsen_scheme_used = coarsen_scheme_used;
cgrid->level = grid->level + 1;
cgrid->n = cA->m;
cgrid->A = cA;
cgrid->D = cD;
cgrid->P = P;
grid->R = R;
cgrid->prev = grid;
cgrid = Multilevel_establish(cgrid, ctrl);
return grid;
}