// ======================================================================
Operator GetScaledOperator(const Operator& A, const double alpha)
{
ML_Operator* ScaledA = 0;
ScaledA = ML_Operator_ExplicitlyScale(A.GetML_Operator(),
(double)alpha);
if (ScaledA == 0)
ML_THROW("ML_Operator_ExplicitlyScale returned 0", -1);
Operator res;
res.Reshape(A.GetDomainSpace(), A.GetRangeSpace(), ScaledA,
true, A.GetRCPOperatorBox());
return(res);
}
// ======================================================================
void GetPtent(const Operator& A, Teuchos::ParameterList& List,
const MultiVector& ThisNS,
Operator& Ptent, MultiVector& NextNS)
{
std::string CoarsenType = List.get("aggregation: type", "Uncoupled");
/* old version
int NodesPerAggr = List.get("aggregation: per aggregate", 64);
*/
double Threshold = List.get("aggregation: threshold", 0.0);
int NumPDEEquations = List.get("PDE equations", 1);
ML_Aggregate* agg_object;
ML_Aggregate_Create(&agg_object);
ML_Aggregate_Set_MaxLevels(agg_object,2);
ML_Aggregate_Set_StartLevel(agg_object,0);
ML_Aggregate_Set_Threshold(agg_object,Threshold);
//agg_object->curr_threshold = 0.0;
ML_Operator* ML_Ptent = 0;
ML_Ptent = ML_Operator_Create(GetML_Comm());
if (ThisNS.GetNumVectors() == 0)
ML_THROW("zero-dimension null space", -1);
int size = ThisNS.GetMyLength();
double* null_vect = 0;
ML_memory_alloc((void **)(&null_vect), sizeof(double) * size * ThisNS.GetNumVectors(), "ns");
int incr = 1;
for (int v = 0 ; v < ThisNS.GetNumVectors() ; ++v)
DCOPY_F77(&size, (double*)ThisNS.GetValues(v), &incr,
null_vect + v * ThisNS.GetMyLength(), &incr);
ML_Aggregate_Set_NullSpace(agg_object, NumPDEEquations,
ThisNS.GetNumVectors(), null_vect,
ThisNS.GetMyLength());
if (CoarsenType == "Uncoupled")
agg_object->coarsen_scheme = ML_AGGR_UNCOUPLED;
else if (CoarsenType == "Uncoupled-MIS")
agg_object->coarsen_scheme = ML_AGGR_HYBRIDUM;
else if (CoarsenType == "MIS") {
/* needed for MIS, otherwise it sets the number of equations to
* the null space dimension */
agg_object->max_levels = -7;
agg_object->coarsen_scheme = ML_AGGR_MIS;
}
else if (CoarsenType == "METIS")
agg_object->coarsen_scheme = ML_AGGR_METIS;
else {
ML_THROW("Requested aggregation scheme (" + CoarsenType +
") not recognized", -1);
}
int NextSize = ML_Aggregate_Coarsen(agg_object, A.GetML_Operator(),
&ML_Ptent, GetML_Comm());
/* This is the old version
int NextSize;
if (CoarsenType == "Uncoupled") {
NextSize = ML_Aggregate_CoarsenUncoupled(agg_object, A.GetML_Operator(),
}
else if (CoarsenType == "MIS") {
NextSize = ML_Aggregate_CoarsenMIS(agg_object, A.GetML_Operator(),
&ML_Ptent, GetML_Comm());
}
else if (CoarsenType == "METIS") {
ML ml_object;
ml_object.ML_num_levels = 1; // crap for line below
ML_Aggregate_Set_NodesPerAggr(&ml_object,agg_object,0,NodesPerAggr);
NextSize = ML_Aggregate_CoarsenMETIS(agg_object, A.GetML_Operator(),
&ML_Ptent, GetML_Comm());
}
else {
ML_THROW("Requested aggregation scheme (" + CoarsenType +
") not recognized", -1);
}
*/
ML_Operator_ChangeToSinglePrecision(ML_Ptent);
int NumMyElements = NextSize;
Space CoarseSpace(-1,NumMyElements);
Ptent.Reshape(CoarseSpace,A.GetRangeSpace(),ML_Ptent,true);
assert (NextSize * ThisNS.GetNumVectors() != 0);
NextNS.Reshape(CoarseSpace, ThisNS.GetNumVectors());
size = NextNS.GetMyLength();
for (int v = 0 ; v < NextNS.GetNumVectors() ; ++v)
DCOPY_F77(&size, agg_object->nullspace_vect + v * size, &incr,
NextNS.GetValues(v), &incr);
ML_Aggregate_Destroy(&agg_object);
ML_memory_free((void**)(&null_vect));
}
