// ============================================================================
// could be made static...
void ML_Epetra::MultiLevelPreconditioner::
RandomAndZero(double * tmp_rhs, double * tmp_sol, int size)
{
// create random numbers between 0.5 and 1.0
ML_random_vec(tmp_rhs, size, ml_comm_);
//for( int i=0 ; i<size ; ++i ) tmp_rhs[i] = 0.5+0.25*tmp_rhs[i];
for( int i=0 ; i<size ; ++i ) tmp_sol[i] = 0.0;
}
int ML_Reitzinger_Check_Hierarchy(ML *ml, ML_Operator **Tmat_array, int incr_or_decr)
{
int i,j;
int finest_level, coarsest_level;
ML_Operator *Amat, *Tmat;
double *randvec, *result, *result1;
double dnorm;
finest_level = ml->ML_finest_level;
coarsest_level = ml->ML_coarsest_level;
if (incr_or_decr == ML_INCREASING) {
if (ml->comm->ML_mypid == 0) {
printf("ML_Reitzinger_Check_Hierarchy: ML_INCREASING is not supported ");
printf(" at this time. Not checking hierarchy.\n");
}
return 1;
}
if ( ML_Get_PrintLevel() > 5 ) {
printf("ML_Reitzinger_Check_Hierarchy: Checking null space\n");
}
for (i=finest_level; i>coarsest_level; i--) {
Amat = ml->Amat+i;
Tmat = Tmat_array[i];
/* normalized random vector */
randvec = (double *) ML_allocate(Tmat->invec_leng * sizeof(double) );
ML_random_vec(randvec,Tmat->invec_leng, ml->comm);
dnorm = sqrt( ML_gdot(Tmat->invec_leng, randvec, randvec, ml->comm) );
for (j=0; j<Tmat->invec_leng; j++) randvec[j] /= dnorm;
result = (double *) ML_allocate(Amat->invec_leng * sizeof(double) );
result1 = (double *) ML_allocate(Amat->outvec_leng * sizeof(double) );
ML_Operator_Apply(Tmat, Tmat->invec_leng, randvec,
Tmat->outvec_leng, result);
ML_Operator_Apply(Amat, Amat->invec_leng, result,
Amat->outvec_leng, result1);
dnorm = sqrt( ML_gdot(Amat->outvec_leng, result1, result1, ml->comm) );
if ( (ML_Get_PrintLevel() > 5) && (ml->comm->ML_mypid == 0) ) {
printf("Level %d: for random v, ||S*T*v|| = %15.10e\n",i,dnorm);
}
ML_free(randvec);
ML_free(result);
ML_free(result1);
}
if ( (ML_Get_PrintLevel() > 5) && (ml->comm->ML_mypid == 0) ) printf("\n");
return 0;
}
int main(int argc, char *argv[])
{
int Nnodes=16*16; /* Total number of nodes in the problem.*/
/* 'Nnodes' must be a perfect square. */
int MaxMgLevels=6; /* Maximum number of Multigrid Levels */
int Nits_per_presmooth=1; /* # of pre & post smoothings per level */
double tolerance = 1.0e-8; /* At convergence: */
/* ||r_k||_2 < tolerance ||r_0||_2 */
int smoothPe_flag = ML_YES; /* ML_YES: smooth tentative prolongator */
/* ML_NO: don't smooth prolongator */
/***************************************************************************/
/* Select Hiptmair relaxation subsmoothers for the nodal and edge problems */
/* Choices include */
/* 1) ML_Gen_Smoother_SymGaussSeidel: this corresponds to a processor */
/* local version of symmetric Gauss-Seidel/SOR. The number of sweeps */
/* can be set via either 'edge_its' or 'nodal_its'. The damping can */
/* be set via 'edge_omega' or 'nodal_omega'. When set to ML_DDEFAULT, */
/* the damping is set to '1' on one processor. On multiple processors */
/* a lower damping value is set. This is needed to converge processor */
/* local SOR. */
/* 2) ML_Gen_Smoother_Cheby: this corresponds to polynomial relaxation. */
/* The degree of the polynomial is set via 'edge_its' or 'nodal_its'. */
/* If the degree is '-1', Marian Brezina's MLS polynomial is chosen. */
/* Otherwise, a Chebyshev polynomial is used over high frequencies */
/* [ lambda_max/alpha , lambda_max]. Lambda_max is computed. 'alpha' */
/* is hardwired in this example to correspond to twice the ratio of */
/* unknowns in the fine and coarse meshes. */
/* */
/* Using 'hiptmair_type' (see comments below) it is also possible to choose*/
/* when edge and nodal problems are relaxed within the Hiptmair smoother. */
/***************************************************************************/
void *edge_smoother=(void *) /* Edge relaxation: */
ML_Gen_Smoother_Cheby; /* ML_Gen_Smoother_Cheby */
/* ML_Gen_Smoother_SymGaussSeidel */
void *nodal_smoother=(void *) /* Nodal relaxation */
ML_Gen_Smoother_Cheby;/* ML_Gen_Smoother_Cheby */
/* ML_Gen_Smoother_SymGaussSeidel */
int edge_its = 3; /* Iterations or polynomial degree for */
int nodal_its = 3; /* edge/nodal subsmoothers. */
double nodal_omega = ML_DDEFAULT, /* SOR damping parameter for noda/edge */
edge_omega = ML_DDEFAULT; /* subsmoothers (see comments above). */
int hiptmair_type=HALF_HIPTMAIR;/* FULL_HIPTMAIR: each invokation */
/* smoothes on edges, then nodes, */
/* and then once again on edges. */
/* HALF_HIPTMAIR: each pre-invokation */
/* smoothes on edges, then nodes. */
/* Each post-invokation smoothes */
/* on nodes then edges. . */
ML_Operator *Tmat, *Tmat_trans, **Tmat_array, **Tmat_trans_array;
ML *ml_edges, *ml_nodes;
ML_Aggregate *ag;
int Nfine_edge, Ncoarse_edge, Nfine_node, Ncoarse_node, Nlevels;
int level, coarsest_level, itmp;
double edge_coarsening_rate, node_coarsening_rate, *rhs, *xxx;
void **edge_args, **nodal_args;
struct user_partition Edge_Partition = {NULL, NULL,0,0},
Node_Partition = {NULL, NULL,0,0};
struct Tmat_data Tmat_data;
int i, Ntotal;
ML_Comm *comm;
/* See Aztec User's Guide for information on these variables */
#ifdef AZTEC
AZ_MATRIX *Ke_mat, *Kn_mat;
AZ_PRECOND *Pmat = NULL;
int proc_config[AZ_PROC_SIZE], options[AZ_OPTIONS_SIZE];
double params[AZ_PARAMS_SIZE], status[AZ_STATUS_SIZE];
#endif
/* get processor information (proc id & # of procs) and set ML's printlevel. */
#ifdef ML_MPI
MPI_Init(&argc,&argv);
#endif
#ifdef AZTEC
AZ_set_proc_config(proc_config, COMMUNICATOR);
#endif
ML_Set_PrintLevel(10); /* set ML's output level: 0 gives least output */
/* Set the # of global nodes/edges and partition both the edges and the */
/* nodes over the processors. NOTE: I believe we assume that if an edge */
/* is assigned to a processor at least one of its nodes must be also */
/* assigned to that processor. */
Node_Partition.Nglobal = Nnodes;
Edge_Partition.Nglobal = Node_Partition.Nglobal*2;
Node_Partition.type = NODE;
Edge_Partition.type = EDGE;
#define perxodic
#ifdef periodic
Node_Partition.Nglobal += 2;
#endif
partition_edges(&Edge_Partition);
partition_nodes(&Node_Partition);
xxx = (double *) ML_allocate((Edge_Partition.Nlocal+100)*sizeof(double));
rhs = (double *) ML_allocate((Edge_Partition.Nlocal+100)*sizeof(double));
for (i = 0; i < Edge_Partition.Nlocal + 100; i++) xxx[i] = -1.;
for (i = 0; i < Edge_Partition.Nlocal; i++) xxx[i] = (double)
Edge_Partition.my_global_ids[i];
update_ghost_edges(xxx, (void *) &Edge_Partition);
/* Create an empty multigrid hierarchy and set the 'MaxMGLevels-1'th */
/* level discretization within this hierarchy to the ML matrix */
/* representing Ke (Maxwell edge discretization). */
ML_Create(&ml_edges, MaxMgLevels);
#ifdef AZTEC
/* Build Ke as an Aztec matrix. Use built-in function AZ_ML_Set_Amat() */
/* to convert to an ML matrix and put in hierarchy. */
Ke_mat = user_Ke_build(&Edge_Partition);
AZ_ML_Set_Amat(ml_edges, MaxMgLevels-1, Edge_Partition.Nlocal,
Edge_Partition.Nlocal, Ke_mat, proc_config);
#else
/* Build Ke directly as an ML matrix. */
ML_Init_Amatrix (ml_edges, MaxMgLevels-1, Edge_Partition.Nlocal,
Edge_Partition.Nlocal, &Edge_Partition);
Ntotal = Edge_Partition.Nlocal;
if (Edge_Partition.nprocs == 2) Ntotal += Edge_Partition.Nghost;
ML_Set_Amatrix_Getrow(ml_edges, MaxMgLevels-1, Ke_getrow, update_ghost_edges, Ntotal);
ML_Set_Amatrix_Matvec(ml_edges, MaxMgLevels-1, Ke_matvec);
#endif
/* Build an Aztec matrix representing an auxiliary nodal PDE problem. */
/* This should be a variable coefficient Poisson problem (with unknowns*/
/* at the nodes). The coefficients should be chosen to reflect the */
/* conductivity of the original edge problems. */
/* Create an empty multigrid hierarchy. Convert the Aztec matrix to an */
/* ML matrix and put it in the 'MaxMGLevels-1' level of the hierarchy. */
/* Note it is possible to multiply T'*T for get this matrix though this*/
/* will not incorporate material properties. */
ML_Create(&ml_nodes, MaxMgLevels);
#ifdef AZTEC
Kn_mat = user_Kn_build( &Node_Partition);
AZ_ML_Set_Amat(ml_nodes, MaxMgLevels-1, Node_Partition.Nlocal,
Node_Partition.Nlocal, Kn_mat, proc_config);
#else
ML_Init_Amatrix (ml_nodes, MaxMgLevels-1 , Node_Partition.Nlocal,
Node_Partition.Nlocal, &Node_Partition);
Ntotal = Node_Partition.Nlocal;
if (Node_Partition.nprocs == 2) Ntotal += Node_Partition.Nghost;
ML_Set_Amatrix_Getrow(ml_nodes, MaxMgLevels-1, Kn_getrow, update_ghost_nodes, Ntotal);
#endif
/* Build an ML matrix representing the null space of the PDE problem. */
/* This should be a discrete gradient (nodes to edges). */
#ifdef AZTEC
Tmat = user_T_build (&Edge_Partition, &Node_Partition,
&(ml_nodes->Amat[MaxMgLevels-1]));
#else
Tmat = ML_Operator_Create(ml_nodes->comm);
Tmat_data.edge = &Edge_Partition;
Tmat_data.node = &Node_Partition;
Tmat_data.Kn = &(ml_nodes->Amat[MaxMgLevels-1]);
ML_Operator_Set_ApplyFuncData( Tmat, Node_Partition.Nlocal,
Edge_Partition.Nlocal, ML_EMPTY, (void *) &Tmat_data,
Edge_Partition.Nlocal, NULL, 0);
ML_Operator_Set_Getrow( Tmat, ML_INTERNAL, Edge_Partition.Nlocal,Tmat_getrow);
ML_Operator_Set_ApplyFunc(Tmat, ML_INTERNAL, Tmat_matvec);
ML_Comm_Create( &comm);
ML_CommInfoOP_Generate( &(Tmat->getrow->pre_comm), update_ghost_nodes,
&Node_Partition,comm, Tmat->invec_leng,
Node_Partition.Nghost);
#endif
/********************************************************************/
/* Set some ML parameters. */
/*------------------------------------------------------------------*/
ML_Set_ResidualOutputFrequency(ml_edges, 1);
ML_Set_Tolerance(ml_edges, 1.0e-8);
ML_Aggregate_Create( &ag );
ML_Aggregate_Set_CoarsenScheme_Uncoupled(ag);
ML_Aggregate_Set_DampingFactor(ag, 0.0); /* must use 0 for maxwell */
ML_Aggregate_Set_MaxCoarseSize(ag, 30);
ML_Aggregate_Set_Threshold(ag, 0.0);
/********************************************************************/
/* Set up Tmat_trans */
/*------------------------------------------------------------------*/
Tmat_trans = ML_Operator_Create(ml_edges->comm);
ML_Operator_Transpose_byrow(Tmat, Tmat_trans);
Nlevels=ML_Gen_MGHierarchy_UsingReitzinger(ml_edges, &ml_nodes,MaxMgLevels-1,
ML_DECREASING,ag,Tmat,Tmat_trans,
&Tmat_array,&Tmat_trans_array,
smoothPe_flag, 1.5);
/* Set the Hiptmair subsmoothers */
if (nodal_smoother == (void *) ML_Gen_Smoother_SymGaussSeidel) {
nodal_args = ML_Smoother_Arglist_Create(2);
ML_Smoother_Arglist_Set(nodal_args, 0, &nodal_its);
ML_Smoother_Arglist_Set(nodal_args, 1, &nodal_omega);
}
if (edge_smoother == (void *) ML_Gen_Smoother_SymGaussSeidel) {
edge_args = ML_Smoother_Arglist_Create(2);
ML_Smoother_Arglist_Set(edge_args, 0, &edge_its);
ML_Smoother_Arglist_Set(edge_args, 1, &edge_omega);
}
if (nodal_smoother == (void *) ML_Gen_Smoother_Cheby) {
nodal_args = ML_Smoother_Arglist_Create(2);
ML_Smoother_Arglist_Set(nodal_args, 0, &nodal_its);
Nfine_node = Tmat_array[MaxMgLevels-1]->invec_leng;
Nfine_node = ML_gsum_int(Nfine_node, ml_edges->comm);
}
if (edge_smoother == (void *) ML_Gen_Smoother_Cheby) {
edge_args = ML_Smoother_Arglist_Create(2);
ML_Smoother_Arglist_Set(edge_args, 0, &edge_its);
Nfine_edge = Tmat_array[MaxMgLevels-1]->outvec_leng;
Nfine_edge = ML_gsum_int(Nfine_edge, ml_edges->comm);
}
/****************************************************
* Set up smoothers for all levels but the coarsest. *
****************************************************/
coarsest_level = MaxMgLevels - Nlevels;
for (level = MaxMgLevels-1; level > coarsest_level; level--)
{
if (edge_smoother == (void *) ML_Gen_Smoother_Cheby) {
Ncoarse_edge = Tmat_array[level-1]->outvec_leng;
Ncoarse_edge = ML_gsum_int(Ncoarse_edge, ml_edges->comm);
edge_coarsening_rate = 2.*((double) Nfine_edge)/ ((double) Ncoarse_edge);
ML_Smoother_Arglist_Set(edge_args, 1, &edge_coarsening_rate);
Nfine_edge = Ncoarse_edge;
}
if (nodal_smoother == (void *) ML_Gen_Smoother_Cheby) {
Ncoarse_node = Tmat_array[level-1]->invec_leng;
Ncoarse_node = ML_gsum_int(Ncoarse_node, ml_edges->comm);
node_coarsening_rate = 2.*((double) Nfine_node)/ ((double) Ncoarse_node);
ML_Smoother_Arglist_Set(nodal_args, 1, &node_coarsening_rate);
Nfine_node = Ncoarse_node;
}
ML_Gen_Smoother_Hiptmair(ml_edges, level, ML_BOTH, Nits_per_presmooth,
Tmat_array, Tmat_trans_array, NULL, edge_smoother,
edge_args, nodal_smoother,nodal_args, hiptmair_type);
}
/*******************************************
* Set up coarsest level smoother
*******************************************/
if (edge_smoother == (void *) ML_Gen_Smoother_Cheby) {
edge_coarsening_rate = (double) Nfine_edge;
ML_Smoother_Arglist_Set(edge_args, 1, &edge_coarsening_rate);
}
if (nodal_smoother == (void *) ML_Gen_Smoother_Cheby) {
node_coarsening_rate = (double) Nfine_node;
ML_Smoother_Arglist_Set(nodal_args,1,&node_coarsening_rate);
}
ML_Gen_CoarseSolverSuperLU( ml_edges, coarsest_level);
/* Must be called before invoking the preconditioner */
ML_Gen_Solver(ml_edges, ML_MGV, MaxMgLevels-1, coarsest_level);
/* Set the initial guess and the right hand side. Invoke solver */
xxx = (double *) ML_allocate(Edge_Partition.Nlocal*sizeof(double));
ML_random_vec(xxx, Edge_Partition.Nlocal, ml_edges->comm);
rhs = (double *) ML_allocate(Edge_Partition.Nlocal*sizeof(double));
ML_random_vec(rhs, Edge_Partition.Nlocal, ml_edges->comm);
#ifdef AZTEC
/* Choose the Aztec solver and criteria. Also tell Aztec that */
/* ML will be supplying the preconditioner. */
AZ_defaults(options, params);
options[AZ_solver] = AZ_fixed_pt;
options[AZ_solver] = AZ_gmres;
options[AZ_kspace] = 80;
params[AZ_tol] = tolerance;
AZ_set_ML_preconditioner(&Pmat, Ke_mat, ml_edges, options);
options[AZ_conv] = AZ_noscaled;
AZ_iterate(xxx, rhs, options, params, status, proc_config, Ke_mat, Pmat, NULL);
#else
ML_Iterate(ml_edges, xxx, rhs);
#endif
/* clean up. */
ML_Smoother_Arglist_Delete(&nodal_args);
ML_Smoother_Arglist_Delete(&edge_args);
ML_Aggregate_Destroy(&ag);
ML_Destroy(&ml_edges);
ML_Destroy(&ml_nodes);
#ifdef AZTEC
AZ_free((void *) Ke_mat->data_org);
AZ_free((void *) Ke_mat->val);
AZ_free((void *) Ke_mat->bindx);
if (Ke_mat != NULL) AZ_matrix_destroy(&Ke_mat);
if (Pmat != NULL) AZ_precond_destroy(&Pmat);
if (Kn_mat != NULL) AZ_matrix_destroy(&Kn_mat);
#endif
free(xxx);
free(rhs);
ML_Operator_Destroy(&Tmat);
ML_Operator_Destroy(&Tmat_trans);
ML_MGHierarchy_ReitzingerDestroy(MaxMgLevels-2, &Tmat_array, &Tmat_trans_array);
#ifdef ML_MPI
MPI_Finalize();
#endif
return 0;
}