//! BuildAggregates routine.
virtual void PrintAggregationInformation(const std::string phase, GraphBase const & graph, Aggregates & aggregates, Teuchos::ArrayRCP<unsigned int> & aggStat) const {
const RCP<const Teuchos::Comm<int> > & comm = graph.GetComm();
const LocalOrdinal nRows = graph.GetNodeNumVertices();
const LocalOrdinal nLocalAggregates = aggregates.GetNumAggregates();
if(IsPrint(Statistics1)) {
LO localAggregated = 0;
GO globalAggregated = 0;
GO globalNRows = 0;
for(LO i=0; i<nRows; ++i)
if(aggStat[i] == NodeStats::AGGREGATED) localAggregated++;
sumAll(comm, (GO)localAggregated, globalAggregated);
sumAll(comm, (GO)nRows, globalNRows);
GetOStream(Statistics1, 0) << "Aggregation (UC): " << phase << " Nodes aggregated = " << globalAggregated << " out of " << globalNRows << " nodes" << std::endl;
GO nAggregatesGlobal = 0;
sumAll(comm, (GO)nLocalAggregates, nAggregatesGlobal);
GetOStream(Statistics1, 0) << "Aggregation (UC): " << phase << " Total aggregates = " << nAggregatesGlobal << std::endl;
}
if(IsPrint(Warnings0)) {
GO localNotAggregated = 0;
GO globalNotAggregated = 0;
for(LO i=0; i<nRows; ++i)
if(aggStat[i] != NodeStats::AGGREGATED ) localNotAggregated++;
sumAll(comm, (GO)localNotAggregated, globalNotAggregated);
if(globalNotAggregated > 0)
GetOStream(Warnings0,0) << "Aggregation (UC): " << phase << " (WARNING) " << globalNotAggregated << " unaggregated nodes left" << std::endl;
}
}
int LeftoverAggregationAlgorithm<LocalOrdinal, GlobalOrdinal, Node, LocalMatOps>::RemoveSmallAggs(Aggregates& aggregates, int min_size,
RCP<Xpetra::Vector<double,LO,GO,NO> > & distWeights, const MueLu::CoupledAggregationCommHelper<LO,GO,NO,LMO> & myWidget) const {
int myPid = aggregates.GetMap()->getComm()->getRank();
LO nAggregates = aggregates.GetNumAggregates();
ArrayRCP<LO> procWinner = aggregates.GetProcWinner()->getDataNonConst(0);
ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
LO size = procWinner.size();
//ArrayRCP<int> AggInfo = Teuchos::arcp<int>(nAggregates+1);
//aggregates.ComputeAggSizes(AggInfo);
ArrayRCP<LO> AggInfo = aggregates.ComputeAggregateSizes();
ArrayRCP<double> weights = distWeights->getDataNonConst(0);
// Make a list of all aggregates indicating New AggId
// Use AggInfo array for this.
LO NewNAggs = 0;
for (LO i = 0; i < nAggregates; i++) {
if ( AggInfo[i] < min_size) {
AggInfo[i] = MUELU_UNAGGREGATED;
}
else AggInfo[i] = NewNAggs++;
}
for (LO k = 0; k < size; k++ ) {
if (procWinner[k] == myPid) {
if (vertex2AggId[k] != MUELU_UNAGGREGATED) {
vertex2AggId[k] = AggInfo[vertex2AggId[k]];
weights[k] = 1.;
}
if (vertex2AggId[k] == MUELU_UNAGGREGATED)
aggregates.SetIsRoot(k,false);
}
}
nAggregates = NewNAggs;
//TODO JJH We want to skip this call
myWidget.ArbitrateAndCommunicate(*distWeights, aggregates, true);
// All tentatively assigned vertices are now definitive
// procWinner is not set correctly for aggregates which have
// been eliminated
for (LO i = 0; i < size; i++) {
if (vertex2AggId[i] == MUELU_UNAGGREGATED)
procWinner[i] = MUELU_UNASSIGNED;
}
aggregates.SetNumAggregates(nAggregates);
return 0; //TODO
} //RemoveSmallAggs
void EmergencyAggregationAlgorithm<LocalOrdinal, GlobalOrdinal, Node, LocalMatOps>::BuildAggregates(const ParameterList& params, const GraphBase& graph, Aggregates& aggregates, std::vector<unsigned>& aggStat, LO& numNonAggregatedNodes) const {
Monitor m(*this, "BuildAggregates");
// vertex ids for output
ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
ArrayRCP<LO> procWinner = aggregates.GetProcWinner() ->getDataNonConst(0);
const LO nRows = graph.GetNodeNumVertices();
const int myRank = graph.GetComm()->getRank();
int aggIndex = -1;
size_t aggSize = 0;
std::vector<int> aggList(graph.getNodeMaxNumRowEntries());
LO nLocalAggregates = aggregates.GetNumAggregates();
for (LO iNode = 0; iNode < nRows; iNode++) {
if (aggStat[iNode] != NodeStats::AGGREGATED) {
aggSize = 0;
aggregates.SetIsRoot(iNode);
aggList[aggSize++] = iNode;
aggIndex = nLocalAggregates++;
ArrayView<const LO> neighOfINode = graph.getNeighborVertices(iNode);
for (LO j = 0; j < neighOfINode.size(); j++) {
LO neigh = neighOfINode[j];
if (neigh != iNode && graph.isLocalNeighborVertex(neigh) && aggStat[neigh] != NodeStats::AGGREGATED)
aggList[aggSize++] = neigh;
}
// finalize aggregate
for (size_t k = 0; k < aggSize; k++) {
aggStat [aggList[k]] = NodeStats::AGGREGATED;
vertex2AggId[aggList[k]] = aggIndex;
procWinner [aggList[k]] = myRank;
}
numNonAggregatedNodes -= aggSize;
}
}
aggregates.SetNumAggregates(nLocalAggregates);
}
void OnePtAggregationAlgorithm<LocalOrdinal, GlobalOrdinal, Node>::BuildAggregates(Teuchos::ParameterList const & params, GraphBase const & graph, Aggregates & aggregates, std::vector<unsigned>& aggStat, LO& numNonAggregatedNodes) const {
Monitor m(*this, "BuildAggregates");
const LocalOrdinal nRows = graph.GetNodeNumVertices();
const int myRank = graph.GetComm()->getRank();
// vertex ids for output
Teuchos::ArrayRCP<LocalOrdinal> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
Teuchos::ArrayRCP<LocalOrdinal> procWinner = aggregates.GetProcWinner()->getDataNonConst(0);
// some internal variables
LocalOrdinal nLocalAggregates = aggregates.GetNumAggregates(); // number of local aggregates on current proc
LocalOrdinal iNode1 = 0; // current node
// main loop over all local rows of grpah(A)
while (iNode1 < nRows) {
if (aggStat[iNode1] == ONEPT) {
aggregates.SetIsRoot(iNode1); // mark iNode1 as root node for new aggregate 'ag'
Aggregate ag;
ag.list.push_back(iNode1);
ag.index = nLocalAggregates++;
// finalize aggregate
for(size_t k=0; k<ag.list.size(); k++) {
aggStat[ag.list[k]] = IGNORED;
vertex2AggId[ag.list[k]] = ag.index;
procWinner[ag.list[k]] = myRank;
}
numNonAggregatedNodes -= ag.list.size();
}
iNode1++;
} // end while
// update aggregate object
aggregates.SetNumAggregates(nLocalAggregates);
}
void UncoupledAggregationAlgorithm<LocalOrdinal, GlobalOrdinal, Node, LocalMatOps>::
BuildAggregates(const ParameterList& params, const GraphBase& graph, Aggregates& aggregates, std::vector<unsigned>& aggStat,
LO& numNonAggregatedNodes) const {
Monitor m(*this, "BuildAggregates");
AggOptions::Ordering ordering = params.get<AggOptions::Ordering>("Ordering");
LO MaxNeighAlreadySelected = params.get<LO> ("MaxNeighAlreadySelected");
LO MinNodesPerAggregate = params.get<LO> ("MinNodesPerAggregate");
LO MaxNodesPerAggregate = params.get<LO> ("MaxNodesPerAggregate");
TEUCHOS_TEST_FOR_EXCEPTION(MaxNodesPerAggregate < MinNodesPerAggregate, Exceptions::RuntimeError, "MueLu::UncoupledAggregationAlgorithm::BuildAggregates: MinNodesPerAggregate must be smaller or equal to MaxNodePerAggregate!");
if (ordering != NATURAL && ordering != RANDOM && ordering != GRAPH)
throw Exceptions::RuntimeError("UncoupledAggregation::BuildAggregates : bad aggregation ordering option");
const LO nRows = graph.GetNodeNumVertices();
const int myRank = graph.GetComm()->getRank();
// vertex ids for output
Teuchos::ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
Teuchos::ArrayRCP<LO> procWinner = aggregates.GetProcWinner() ->getDataNonConst(0);
// some internal variables
LO nLocalAggregates = aggregates.GetNumAggregates(); // number of local aggregates on current proc
std::queue<LO> graph_ordering_inodes; // inodes for graph ordering
ArrayRCP<LO> randomVector;
if (ordering == RANDOM) {
randomVector = arcp<LO>(nRows);
for (LO i = 0; i < nRows; i++)
randomVector[i] = i;
RandomReorder(randomVector);
}
int aggIndex = -1;
size_t aggSize = 0;
std::vector<int> aggList(graph.getNodeMaxNumRowEntries());
// Main loop over all local rows of graph(A)
for (LO iNode2 = 0; iNode2 < nRows; iNode2++) {
// Step 1: pick the next node to aggregate
LO iNode1 = 0;
if (ordering == NATURAL) iNode1 = iNode2;
else if (ordering == RANDOM) iNode1 = randomVector[iNode2];
else if (ordering == GRAPH) {
if (graph_ordering_inodes.size() == 0) {
// There are no nodes for graph ordering scheme,
// add exactly one ready node for graph ordering aggregates
for (LO jnode = 0; jnode < nRows; jnode++)
if (aggStat[jnode] == NodeStats::READY) {
graph_ordering_inodes.push(jnode);
break;
}
}
if (graph_ordering_inodes.size() == 0) {
// There are no more ready nodes, end the phase
break;
}
iNode1 = graph_ordering_inodes.front(); // take next node from graph ordering queue
graph_ordering_inodes.pop(); // delete this node in list
}
if (aggStat[iNode1] == NodeStats::READY) {
// Step 2: build tentative aggregate
aggSize = 0;
aggList[aggSize++] = iNode1;
ArrayView<const LO> neighOfINode = graph.getNeighborVertices(iNode1);
LO numAggregatedNeighbours = 0;
// NOTE: if neighOfINode.size() < MinNodesPerAggregate, we could skip this loop,
// but only for NATURAL and RANDOM (for GRAPH we still need the list of local neighbors)
for (LO j = 0; j < neighOfINode.size(); j++) {
LO neigh = neighOfINode[j];
if (neigh != iNode1 && graph.isLocalNeighborVertex(neigh)) {
if (aggStat[neigh] == NodeStats::READY || aggStat[neigh] == NodeStats::NOTSEL) {
// Add neighbor node to tentative aggregate
// but only if aggregate size is not exceeding maximum size
// NOTE: We do not exit the loop over all neighbours since we have still
// to count all aggregated neighbour nodes for the aggregation criteria
// NOTE: We check here for the maximum aggregation size. If we would do it below
// with all the other check too big aggregates would not be accepted at all.
if (aggSize < as<size_t>(MaxNodesPerAggregate))
aggList[aggSize++] = neigh;
} else {
numAggregatedNeighbours++;
}
}
}
// Step 3: check if tentative aggregate is acceptable
if ((numAggregatedNeighbours <= MaxNeighAlreadySelected) && // too many connections to other aggregates
(as<LO>(aggSize) >= MinNodesPerAggregate)) { // too few nodes in the tentative aggregate
// Accept new aggregate
// iNode1 becomes the root of the newly formed aggregate
aggregates.SetIsRoot(iNode1);
aggIndex = nLocalAggregates++;
for (size_t k = 0; k < aggSize; k++) {
aggStat [aggList[k]] = NodeStats::AGGREGATED;
vertex2AggId[aggList[k]] = aggIndex;
procWinner [aggList[k]] = myRank;
if (ordering == GRAPH) {
Teuchos::ArrayView<const LO> neighOfJNode = graph.getNeighborVertices(aggList[k]);
for (int j = 0; j < neighOfJNode.size(); j++) {
LO neigh = neighOfJNode[j];
if (graph.isLocalNeighborVertex(neigh) && aggStat[neigh] == NodeStats::READY)
graph_ordering_inodes.push(neigh);
}
}
}
numNonAggregatedNodes -= aggSize;
} else {
// Aggregate is not accepted
aggStat[iNode1] = NodeStats::NOTSEL;
if (ordering == GRAPH) {
// Even though the aggregate around iNode1 is not perfect, we want to try
// the neighbor nodes of iNode1
for (int j = 0; j < neighOfINode.size(); j++) {
LO neigh = neighOfINode[j];
if (graph.isLocalNeighborVertex(neigh) && aggStat[neigh] == NodeStats::READY)
graph_ordering_inodes.push(neigh);
}
}
}
}
}
// update aggregate object
aggregates.SetNumAggregates(nLocalAggregates);
}
void AmalgamationInfo<LocalOrdinal, GlobalOrdinal, Node, LocalMatOps>::UnamalgamateAggregates(const Aggregates& aggregates,
Teuchos::ArrayRCP<LocalOrdinal>& aggStart, Teuchos::ArrayRCP<GlobalOrdinal>& aggToRowMap) const {
int myPid = aggregates.GetMap()->getComm()->getRank();
Teuchos::ArrayView<const GO> nodeGlobalElts = aggregates.GetMap()->getNodeElementList();
Teuchos::ArrayRCP<LO> procWinner = aggregates.GetProcWinner()->getDataNonConst(0);
Teuchos::ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
LO size = procWinner.size();
GO numAggregates = aggregates.GetNumAggregates();
std::vector<LO> sizes(numAggregates);
if (stridedblocksize_ == 1) {
for (LO lnode = 0; lnode < size; ++lnode) {
LO myAgg = vertex2AggId[lnode];
if (procWinner[lnode] == myPid)
sizes[myAgg] += 1;
}
} else {
for (LO lnode = 0; lnode < size; ++lnode) {
LO myAgg = vertex2AggId[lnode];
if (procWinner[lnode] == myPid) {
GO gnodeid = nodeGlobalElts[lnode];
for (LocalOrdinal k = 0; k < stridedblocksize_; k++) {
GlobalOrdinal gDofIndex = ComputeGlobalDOF(gnodeid,k);
if (columnMap_->isNodeGlobalElement(gDofIndex))
sizes[myAgg] += 1;
}
}
}
}
aggStart = ArrayRCP<LO>(numAggregates+1,0);
aggStart[0]=0;
for (GO i=0; i<numAggregates; ++i) {
aggStart[i+1] = aggStart[i] + sizes[i];
}
aggToRowMap = ArrayRCP<GO>(aggStart[numAggregates],0);
// count, how many dofs have been recorded for each aggregate so far
Array<LO> numDofs(numAggregates, 0); // empty array with number of Dofs for each aggregate
if (stridedblocksize_ == 1) {
for (LO lnode = 0; lnode < size; ++lnode) {
LO myAgg = vertex2AggId[lnode];
if (procWinner[lnode] == myPid) {
aggToRowMap[ aggStart[myAgg] + numDofs[myAgg] ] = ComputeGlobalDOF(nodeGlobalElts[lnode]);
++(numDofs[myAgg]);
}
}
} else {
for (LO lnode = 0; lnode < size; ++lnode) {
LO myAgg = vertex2AggId[lnode];
if (procWinner[lnode] == myPid) {
GO gnodeid = nodeGlobalElts[lnode];
for (LocalOrdinal k = 0; k < stridedblocksize_; k++) {
GlobalOrdinal gDofIndex = ComputeGlobalDOF(gnodeid,k);
if (columnMap_->isNodeGlobalElement(gDofIndex)) {
aggToRowMap[ aggStart[myAgg] + numDofs[myAgg] ] = gDofIndex;
++(numDofs[myAgg]);
}
}
}
}
}
// todo plausibility check: entry numDofs[k] == aggToRowMap[k].size()
} //UnamalgamateAggregates
void AmalgamationInfo<LocalOrdinal, GlobalOrdinal, Node, LocalMatOps>::UnamalgamateAggregatesLO(const Aggregates& aggregates,
Teuchos::ArrayRCP<LO>& aggStart, Teuchos::ArrayRCP<LO>& aggToRowMap) const {
int myPid = aggregates.GetMap()->getComm()->getRank();
Teuchos::ArrayView<const GO> nodeGlobalElts = aggregates.GetMap()->getNodeElementList();
Teuchos::ArrayRCP<LO> procWinner = aggregates.GetProcWinner() ->getDataNonConst(0);
Teuchos::ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
const GO numAggregates = aggregates.GetNumAggregates();
// FIXME: Do we need to compute size here? Or can we use existing?
LO size = procWinner.size();
std::vector<LO> sizes(numAggregates);
if (stridedblocksize_ == 1) {
for (LO lnode = 0; lnode < size; lnode++)
if (procWinner[lnode] == myPid)
sizes[vertex2AggId[lnode]]++;
} else {
for (LO lnode = 0; lnode < size; lnode++)
if (procWinner[lnode] == myPid) {
GO nodeGID = nodeGlobalElts[lnode];
for (LO k = 0; k < stridedblocksize_; k++) {
GO GID = ComputeGlobalDOF(nodeGID, k);
if (columnMap_->isNodeGlobalElement(GID))
sizes[vertex2AggId[lnode]]++;
}
}
}
aggStart = ArrayRCP<LO>(numAggregates+1); // FIXME: useless initialization with zeros
aggStart[0] = 0;
for (GO i = 0; i < numAggregates; i++)
aggStart[i+1] = aggStart[i] + sizes[i];
aggToRowMap = ArrayRCP<LO>(aggStart[numAggregates], 0);
// count, how many dofs have been recorded for each aggregate so far
Array<LO> numDofs(numAggregates, 0); // empty array with number of DOFs for each aggregate
if (stridedblocksize_ == 1) {
for (LO lnode = 0; lnode < size; ++lnode)
if (procWinner[lnode] == myPid) {
LO myAgg = vertex2AggId[lnode];
aggToRowMap[aggStart[myAgg] + numDofs[myAgg]] = lnode;
numDofs[myAgg]++;
}
} else {
for (LO lnode = 0; lnode < size; ++lnode)
if (procWinner[lnode] == myPid) {
LO myAgg = vertex2AggId[lnode];
GO nodeGID = nodeGlobalElts[lnode];
for (LO k = 0; k < stridedblocksize_; k++) {
GO GID = ComputeGlobalDOF(nodeGID, k);
if (columnMap_->isNodeGlobalElement(GID)) {
aggToRowMap[aggStart[myAgg] + numDofs[myAgg]] = lnode*stridedblocksize_ + k;
numDofs[myAgg]++;
}
}
}
}
// todo plausibility check: entry numDofs[k] == aggToRowMap[k].size()
} //UnamalgamateAggregates
void AggregationPhase2aAlgorithm<LocalOrdinal, GlobalOrdinal, Node, LocalMatOps>::BuildAggregates(const ParameterList& params, const GraphBase& graph, Aggregates& aggregates, std::vector<unsigned>& aggStat, LO& numNonAggregatedNodes) const {
Monitor m(*this, "BuildAggregates");
LO minNodesPerAggregate = params.get<LO>("aggregation: min agg size");
LO maxNodesPerAggregate = params.get<LO>("aggregation: max agg size");
const LO numRows = graph.GetNodeNumVertices();
const int myRank = graph.GetComm()->getRank();
ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
ArrayRCP<LO> procWinner = aggregates.GetProcWinner() ->getDataNonConst(0);
LO numLocalAggregates = aggregates.GetNumAggregates();
LO numLocalNodes = procWinner.size();
LO numLocalAggregated = numLocalNodes - numNonAggregatedNodes;
const double aggFactor = 0.5;
double factor = as<double>(numLocalAggregated)/(numLocalNodes+1);
factor = pow(factor, aggFactor);
int aggIndex = -1;
size_t aggSize = 0;
std::vector<int> aggList(graph.getNodeMaxNumRowEntries());
for (LO rootCandidate = 0; rootCandidate < numRows; rootCandidate++) {
if (aggStat[rootCandidate] != READY)
continue;
aggSize = 0;
ArrayView<const LocalOrdinal> neighOfINode = graph.getNeighborVertices(rootCandidate);
LO numNeighbors = 0;
for (int j = 0; j < neighOfINode.size(); j++) {
LO neigh = neighOfINode[j];
if (neigh != rootCandidate) {
if (graph.isLocalNeighborVertex(neigh) && aggStat[neigh] == READY) {
// If aggregate size does not exceed max size, add node to the tentative aggregate
// NOTE: We do not exit the loop over all neighbours since we have still
// to count all aggregated neighbour nodes for the aggregation criteria
// NOTE: We check here for the maximum aggregation size. If we would do it below
// with all the other check too big aggregates would not be accepted at all.
if (aggSize < as<size_t>(maxNodesPerAggregate))
aggList[aggSize++] = neigh;
}
numNeighbors++;
}
}
// NOTE: ML uses a hardcoded value 3 instead of MinNodesPerAggregate
if (aggSize > as<size_t>(minNodesPerAggregate) &&
aggSize > factor*numNeighbors) {
// Accept new aggregate
// rootCandidate becomes the root of the newly formed aggregate
aggregates.SetIsRoot(rootCandidate);
aggIndex = numLocalAggregates++;
for (size_t k = 0; k < aggSize; k++) {
aggStat [aggList[k]] = AGGREGATED;
vertex2AggId[aggList[k]] = aggIndex;
procWinner [aggList[k]] = myRank;
}
numNonAggregatedNodes -= aggSize;
}
}
// update aggregate object
aggregates.SetNumAggregates(numLocalAggregates);
}
void LeftoverAggregationAlgorithm<LocalOrdinal, GlobalOrdinal, Node, LocalMatOps>::AggregateLeftovers(GraphBase const &graph, Aggregates &aggregates) const {
Monitor m(*this, "AggregateLeftovers");
my_size_t nVertices = graph.GetNodeNumVertices();
int exp_nRows = aggregates.GetMap()->getNodeNumElements(); // Tentative fix... was previously exp_nRows = nVertices + graph.GetNodeNumGhost();
int myPid = graph.GetComm()->getRank();
my_size_t nAggregates = aggregates.GetNumAggregates();
int minNodesPerAggregate = GetMinNodesPerAggregate();
const RCP<const Map> nonUniqueMap = aggregates.GetMap(); //column map of underlying graph
const RCP<const Map> uniqueMap = graph.GetDomainMap();
MueLu::CoupledAggregationCommHelper<LO,GO,NO,LMO> myWidget(uniqueMap, nonUniqueMap);
//TODO JJH We want to skip this call
RCP<Xpetra::Vector<double,LO,GO,NO> > distWeights = Xpetra::VectorFactory<double,LO,GO,NO>::Build(nonUniqueMap);
// Aggregated vertices not "definitively" assigned to processors are
// arbitrated by ArbitrateAndCommunicate(). There is some
// additional logic to prevent losing root nodes in arbitration.
{
ArrayRCP<const LO> vertex2AggId = aggregates.GetVertex2AggId()->getData(0);
ArrayRCP<const LO> procWinner = aggregates.GetProcWinner()->getData(0);
ArrayRCP<double> weights = distWeights->getDataNonConst(0);
for (size_t i=0;i<nonUniqueMap->getNodeNumElements();i++) {
if (procWinner[i] == MUELU_UNASSIGNED) {
if (vertex2AggId[i] != MUELU_UNAGGREGATED) {
weights[i] = 1.;
if (aggregates.IsRoot(i)) weights[i] = 2.;
}
}
}
// views on distributed vectors are freed here.
}
//TODO JJH We want to skip this call
myWidget.ArbitrateAndCommunicate(*distWeights, aggregates, true);
// All tentatively assigned vertices are now definitive
// Tentatively assign any vertex (ghost or local) which neighbors a root
// to the aggregate associated with the root.
{
ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
ArrayRCP<const LO> procWinner = aggregates.GetProcWinner()->getData(0);
ArrayRCP<double> weights = distWeights->getDataNonConst(0);
for (my_size_t i = 0; i < nVertices; i++) {
if ( aggregates.IsRoot(i) && (procWinner[i] == myPid) ) {
// neighOfINode is the neighbor node list of node 'i'.
ArrayView<const LO> neighOfINode = graph.getNeighborVertices(i);
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int colj = *it;
if (vertex2AggId[colj] == MUELU_UNAGGREGATED) {
weights[colj]= 1.;
vertex2AggId[colj] = vertex2AggId[i];
}
}
}
}
// views on distributed vectors are freed here.
}
//TODO JJH We want to skip this call
myWidget.ArbitrateAndCommunicate(*distWeights, aggregates, true);
// All tentatively assigned vertices are now definitive
// Record the number of aggregated vertices
GO total_phase_one_aggregated = 0;
{
ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
GO phase_one_aggregated = 0;
for (my_size_t i = 0; i < nVertices; i++) {
if (vertex2AggId[i] != MUELU_UNAGGREGATED)
phase_one_aggregated++;
}
sumAll(graph.GetComm(), phase_one_aggregated, total_phase_one_aggregated);
GO local_nVertices = nVertices, total_nVertices = 0;
sumAll(graph.GetComm(), local_nVertices, total_nVertices);
/* Among unaggregated points, see if we can make a reasonable size */
/* aggregate out of it. We do this by looking at neighbors and seeing */
/* how many are unaggregated and on my processor. Loosely, */
/* base the number of new aggregates created on the percentage of */
/* unaggregated nodes. */
ArrayRCP<double> weights = distWeights->getDataNonConst(0);
double factor = 1.;
factor = ((double) total_phase_one_aggregated)/((double)(total_nVertices + 1));
factor = pow(factor, GetPhase3AggCreation());
for (my_size_t i = 0; i < nVertices; i++) {
if (vertex2AggId[i] == MUELU_UNAGGREGATED)
{
// neighOfINode is the neighbor node list of node 'iNode'.
ArrayView<const LO> neighOfINode = graph.getNeighborVertices(i);
int rowi_N = neighOfINode.size();
int nonaggd_neighbors = 0;
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int colj = *it;
if (vertex2AggId[colj] == MUELU_UNAGGREGATED && colj < nVertices)
nonaggd_neighbors++;
}
if ( (nonaggd_neighbors > minNodesPerAggregate) &&
(((double) nonaggd_neighbors)/((double) rowi_N) > factor))
{
vertex2AggId[i] = (nAggregates)++;
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int colj = *it;
if (vertex2AggId[colj]==MUELU_UNAGGREGATED) {
vertex2AggId[colj] = vertex2AggId[i];
if (colj < nVertices) weights[colj] = 2.;
else weights[colj] = 1.;
}
}
aggregates.SetIsRoot(i);
weights[i] = 2.;
}
}
} // for (i = 0; i < nVertices; i++)
// views on distributed vectors are freed here.
}
//TODO JJH We want to skip this call
myWidget.ArbitrateAndCommunicate(*distWeights, aggregates, true);
//All tentatively assigned vertices are now definitive
if (IsPrint(Statistics1)) {
GO Nphase1_agg = nAggregates;
GO total_aggs;
sumAll(graph.GetComm(), Nphase1_agg, total_aggs);
GetOStream(Statistics1, 0) << "Phase 1 - nodes aggregated = " << total_phase_one_aggregated << std::endl;
GetOStream(Statistics1, 0) << "Phase 1 - total aggregates = " << total_aggs << std::endl;
GO i = nAggregates - Nphase1_agg;
{ GO ii; sumAll(graph.GetComm(),i,ii); i = ii; }
GetOStream(Statistics1, 0) << "Phase 3 - additional aggregates = " << i << std::endl;
}
// Determine vertices that are not shared by setting Temp to all ones
// and doing NonUnique2NonUnique(..., ADD). This sums values of all
// local copies associated with each Gid. Thus, sums > 1 are shared.
// std::cout << "exp_nrows=" << exp_nRows << " (nVertices= " << nVertices << ", numGhost=" << graph.GetNodeNumGhost() << ")" << std::endl;
// std::cout << "nonUniqueMap=" << nonUniqueMap->getNodeNumElements() << std::endl;
RCP<Xpetra::Vector<double,LO,GO,NO> > temp_ = Xpetra::VectorFactory<double,LO,GO,NO> ::Build(nonUniqueMap,false); //no need to zero out vector in ctor
temp_->putScalar(1.);
RCP<Xpetra::Vector<double,LO,GO,NO> > tempOutput_ = Xpetra::VectorFactory<double,LO,GO,NO> ::Build(nonUniqueMap);
myWidget.NonUnique2NonUnique(*temp_, *tempOutput_, Xpetra::ADD);
std::vector<bool> gidNotShared(exp_nRows);
{
ArrayRCP<const double> tempOutput = tempOutput_->getData(0);
for (int i = 0; i < exp_nRows; i++) {
if (tempOutput[i] > 1.)
gidNotShared[i] = false;
else
gidNotShared[i] = true;
}
}
// Phase 4.
double nAggregatesTarget;
nAggregatesTarget = ((double) uniqueMap->getGlobalNumElements())* (((double) uniqueMap->getGlobalNumElements())/ ((double) graph.GetGlobalNumEdges()));
GO nAggregatesLocal=nAggregates, nAggregatesGlobal; sumAll(graph.GetComm(), nAggregatesLocal, nAggregatesGlobal);
LO minNAggs; minAll(graph.GetComm(), nAggregates, minNAggs);
LO maxNAggs; maxAll(graph.GetComm(), nAggregates, maxNAggs);
//
// Only do this phase if things look really bad. THIS
// CODE IS PRETTY EXPERIMENTAL
//
#define MUELU_PHASE4BUCKETS 6
if ((nAggregatesGlobal < graph.GetComm()->getSize()) &&
(2.5*nAggregatesGlobal < nAggregatesTarget) &&
(minNAggs ==0) && (maxNAggs <= 1)) {
// Modify seed of the random algorithm used by temp_->randomize()
{
typedef Teuchos::ScalarTraits<double> scalarTrait; // temp_ is of type double.
scalarTrait::seedrandom(static_cast<unsigned int>(myPid*2 + (int) (11*scalarTrait::random())));
int k = (int)ceil( (10.*myPid)/graph.GetComm()->getSize());
for (int i = 0; i < k+7; i++) scalarTrait::random();
temp_->setSeed(static_cast<unsigned int>(scalarTrait::random()));
}
temp_->randomize();
ArrayRCP<double> temp = temp_->getDataNonConst(0);
// build a list of candidate root nodes (vertices not adjacent
// to aggregated vertices)
my_size_t nCandidates = 0;
global_size_t nCandidatesGlobal;
ArrayRCP<LO> candidates = Teuchos::arcp<LO>(nVertices+1);
double priorThreshold = 0.;
for (int kkk = 0; kkk < MUELU_PHASE4BUCKETS; kkk++) {
{
ArrayRCP<const LO> vertex2AggId = aggregates.GetVertex2AggId()->getData(0);
ArrayView<const LO> vertex2AggIdView = vertex2AggId();
RootCandidates(nVertices, vertex2AggIdView, graph, candidates, nCandidates, nCandidatesGlobal);
// views on distributed vectors are freed here.
}
double nTargetNewGuys = nAggregatesTarget - nAggregatesGlobal;
double threshold = priorThreshold + (1. - priorThreshold)*nTargetNewGuys/(nCandidatesGlobal + .001);
threshold = (threshold*(kkk+1.))/((double) MUELU_PHASE4BUCKETS);
priorThreshold = threshold;
{
ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
ArrayRCP<double> weights = distWeights->getDataNonConst(0);
for (int k = 0; k < nCandidates; k++ ) {
int i = candidates[k];
if ((vertex2AggId[i] == MUELU_UNAGGREGATED) && (fabs(temp[i]) < threshold)) {
// Note: priorThreshold <= fabs(temp[i]) <= 1
// neighOfINode is the neighbor node list of node 'iNode'.
ArrayView<const LO> neighOfINode = graph.getNeighborVertices(i);
if (neighOfINode.size() > minNodesPerAggregate) { //TODO: check if this test is exactly was we want to do
int count = 0;
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int Adjacent = *it;
// This might not be true if someone close to i
// is chosen as a root via fabs(temp[]) < Threshold
if (vertex2AggId[Adjacent] == MUELU_UNAGGREGATED){
count++;
vertex2AggId[Adjacent] = nAggregates;
weights[Adjacent] = 1.;
}
}
if (count >= minNodesPerAggregate) {
vertex2AggId[i] = nAggregates++;
weights[i] = 2.;
aggregates.SetIsRoot(i);
}
else { // undo things
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int Adjacent = *it;
if (vertex2AggId[Adjacent] == nAggregates){
vertex2AggId[Adjacent] = MUELU_UNAGGREGATED;
weights[Adjacent] = 0.;
}
}
}
}
}
}
// views on distributed vectors are freed here.
}
//TODO JJH We want to skip this call
myWidget.ArbitrateAndCommunicate(*distWeights, aggregates, true);
// All tentatively assigned vertices are now definitive
nAggregatesLocal=nAggregates;
sumAll(graph.GetComm(), nAggregatesLocal, nAggregatesGlobal);
// check that there are no aggregates sizes below minNodesPerAggregate
aggregates.SetNumAggregates(nAggregates);
RemoveSmallAggs(aggregates, minNodesPerAggregate, distWeights, myWidget);
nAggregates = aggregates.GetNumAggregates();
} // one possibility
}
// Initialize things for Phase 5. This includes building the transpose
// of the matrix ONLY for transposed rows that correspond to unaggregted
// ghost vertices. Further, the transpose is only a local transpose.
// Nonzero edges which exist on other processors are not represented.
int observedNAgg=-1; //number of aggregates that contain vertices on this process
{
ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
ArrayRCP<const LO> procWinner = aggregates.GetProcWinner()->getData(0);
for(LO k = 0; k < vertex2AggId.size(); ++k )
if(vertex2AggId[k]>observedNAgg)
observedNAgg=vertex2AggId[k];
observedNAgg++;
}
ArrayRCP<int> Mark = Teuchos::arcp<int>(exp_nRows+1);
ArrayRCP<int> agg_incremented = Teuchos::arcp<int>(observedNAgg);
ArrayRCP<int> SumOfMarks = Teuchos::arcp<int>(observedNAgg);
for (int i = 0; i < exp_nRows; i++) Mark[i] = MUELU_DISTONE_VERTEX_WEIGHT;
for (int i = 0; i < agg_incremented.size(); i++) agg_incremented[i] = 0;
for (int i = 0; i < SumOfMarks.size(); i++) SumOfMarks[i] = 0;
// Grab the transpose matrix graph for unaggregated ghost vertices.
// a) count the number of nonzeros per row in the transpose
std::vector<int> RowPtr(exp_nRows+1-nVertices);
//{
ArrayRCP<const LO> vertex2AggIdCst = aggregates.GetVertex2AggId()->getData(0);
for (int i = nVertices; i < exp_nRows; i++) RowPtr[i-nVertices] = 0;
for (int i = 0; i < nVertices; i++) {
// neighOfINode is the neighbor node list of node 'iNode'.
ArrayView<const LO> neighOfINode = graph.getNeighborVertices(i);
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int j = *it;
if ( (j >= nVertices) && (vertex2AggIdCst[j] == MUELU_UNAGGREGATED)){
RowPtr[j-nVertices]++;
}
}
}
// b) Convert RowPtr[i] to point to 1st first nnz spot in row i.
int iSum = 0, iTemp;
for (int i = nVertices; i < exp_nRows; i++) {
iTemp = RowPtr[i-nVertices];
RowPtr[i-nVertices] = iSum;
iSum += iTemp;
}
RowPtr[exp_nRows-nVertices] = iSum;
std::vector<LO> cols(iSum+1);
// c) Traverse matrix and insert entries in proper location.
for (int i = 0; i < nVertices; i++) {
// neighOfINode is the neighbor node list of node 'iNode'.
ArrayView<const LO> neighOfINode = graph.getNeighborVertices(i);
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int j = *it;
if ( (j >= nVertices) && (vertex2AggIdCst[j] == MUELU_UNAGGREGATED)){
cols[RowPtr[j-nVertices]++] = i;
}
}
}
// d) RowPtr[i] points to beginning of row i+1 so shift by one location.
for (int i = exp_nRows; i > nVertices; i--)
RowPtr[i-nVertices] = RowPtr[i-1-nVertices];
RowPtr[0] = 0;
// views on distributed vectors are freed here.
vertex2AggIdCst = Teuchos::null;
//}
int bestScoreCutoff;
int thresholds[10] = {300,200,100,50,25,13,7,4,2,0};
// Stick unaggregated vertices into existing aggregates as described above.
{
int ncalls=0;
for (int kk = 0; kk < 10; kk += 2) {
bestScoreCutoff = thresholds[kk];
ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
ArrayRCP<const LO> procWinner = aggregates.GetProcWinner()->getData(0);
ArrayRCP<double> weights = distWeights->getDataNonConst(0);
for (int i = 0; i < exp_nRows; i++) {
if (vertex2AggId[i] == MUELU_UNAGGREGATED) {
// neighOfINode is the neighbor node list of node 'iNode'.
ArrayView<const LO> neighOfINode;
// Grab neighboring vertices which is either in graph for local ids
// or sits in transposed fragment just constructed above for ghosts.
if (i < nVertices) {
neighOfINode = graph.getNeighborVertices(i);
}
else {
LO *rowi_col = NULL, rowi_N;
rowi_col = &(cols[RowPtr[i-nVertices]]);
rowi_N = RowPtr[i+1-nVertices] - RowPtr[i-nVertices];
neighOfINode = ArrayView<const LO>(rowi_col, rowi_N);
}
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int Adjacent = *it;
int AdjacentAgg = vertex2AggId[Adjacent];
//Adjacent is aggregated and either I own the aggregate
// or I could own the aggregate after arbitration.
if ((AdjacentAgg != MUELU_UNAGGREGATED) &&
((procWinner[Adjacent] == myPid) ||
(procWinner[Adjacent] == MUELU_UNASSIGNED))){
SumOfMarks[AdjacentAgg] += Mark[Adjacent];
}
}
int best_score = MUELU_NOSCORE;
int best_agg = -1;
int BestMark = -1;
bool cannotLoseAllFriends=false; // Used to address possible loss of vertices in arbitration of shared nodes discussed above. (Initialized to false only to avoid a compiler warning).
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int Adjacent = *it;
int AdjacentAgg = vertex2AggId[Adjacent];
//Adjacent is unaggregated, has some value and no
//other processor has definitively claimed him
if ((AdjacentAgg != MUELU_UNAGGREGATED) &&
(SumOfMarks[AdjacentAgg] != 0) &&
((procWinner[Adjacent] == myPid) ||
(procWinner[Adjacent] == MUELU_UNASSIGNED ))) {
// first figure out the penalty associated with
// AdjacentAgg having already been incremented
// during this phase, then compute score.
double penalty = (double) (INCR_SCALING*agg_incremented[AdjacentAgg]);
if (penalty > MUELU_PENALTYFACTOR*((double)SumOfMarks[AdjacentAgg]))
penalty = MUELU_PENALTYFACTOR*((double)SumOfMarks[AdjacentAgg]);
int score = SumOfMarks[AdjacentAgg]- ((int) floor(penalty));
if (score > best_score) {
best_agg = AdjacentAgg;
best_score = score;
BestMark = Mark[Adjacent];
cannotLoseAllFriends = false;
// This address issue mentioned above by checking whether
// Adjacent could be lost in arbitration. weight==0 means that
// Adjacent was not set during this loop of Phase 5 (and so it
// has already undergone arbitration). GidNotShared == true
// obviously implies that Adjacent cannot be lost to arbitration
if ((weights[Adjacent]== 0.) || (gidNotShared[Adjacent] == true))
cannotLoseAllFriends = true;
}
// Another vertex within current best aggregate found.
// We should have (best_score == score). We need to see
// if we can improve BestMark and cannotLoseAllFriends.
else if (best_agg == AdjacentAgg) {
if ((weights[Adjacent]== 0.) || (gidNotShared[Adjacent] == true))
cannotLoseAllFriends = true;
if (Mark[Adjacent] > BestMark) BestMark = Mark[Adjacent];
}
}
}
// Clean up
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int Adjacent = *it;
int AdjacentAgg = vertex2AggId[Adjacent];
if (AdjacentAgg >= 0) SumOfMarks[AdjacentAgg] = 0;
}
// Tentatively assign vertex to best_agg.
if ( (best_score >= bestScoreCutoff) && (cannotLoseAllFriends)) {
TEUCHOS_TEST_FOR_EXCEPTION(best_agg == -1 || BestMark == -1, MueLu::Exceptions::RuntimeError, "MueLu::CoupledAggregationFactory internal error"); // should never happen
vertex2AggId[i] = best_agg;
weights[i] = best_score;
agg_incremented[best_agg]++;
Mark[i] = (int) ceil( ((double) BestMark)/2.);
}
}
// views on distributed vectors are freed here.
}
vertex2AggId = Teuchos::null;
procWinner = Teuchos::null;
weights = Teuchos::null;
++ncalls;
//TODO JJH We want to skip this call
myWidget.ArbitrateAndCommunicate(*distWeights, aggregates, true);
// All tentatively assigned vertices are now definitive
}
// if (graph.GetComm()->getRank()==0)
// std::cout << "#calls to Arb&Comm=" << ncalls << std::endl;
}
// Phase 6: Aggregate remain unaggregated vertices and try at all costs
// to avoid small aggregates.
// One case where we can find ourselves in this situation
// is if all vertices vk adjacent to v have already been
// put in other processor's aggregates and v does not have
// a direct connection to a local vertex in any of these
// aggregates.
int Nleftover = 0, Nsingle = 0;
{
ArrayRCP<LO> vertex2AggId = aggregates.GetVertex2AggId()->getDataNonConst(0);
ArrayRCP<double> weights = distWeights->getDataNonConst(0);
ArrayRCP<const LO> procWinner = aggregates.GetProcWinner()->getData(0);
int count = 0;
for (my_size_t i = 0; i < nVertices; i++) {
if (vertex2AggId[i] == MUELU_UNAGGREGATED) {
Nleftover++;
// neighOfINode is the neighbor node list of node 'iNode'.
ArrayView<const LO> neighOfINode = graph.getNeighborVertices(i);
// We don't want too small of an aggregate. So lets see if there is an
// unaggregated neighbor that we can also put with this vertex
vertex2AggId[i] = nAggregates;
weights[i] = 1.;
if (count == 0) aggregates.SetIsRoot(i);
count++;
for (typename ArrayView<const LO>::const_iterator it = neighOfINode.begin(); it != neighOfINode.end(); ++it) {
int j = *it;
if ((j != i)&&(vertex2AggId[j] == MUELU_UNAGGREGATED)&&
(j < nVertices)) {
vertex2AggId[j] = nAggregates;
weights[j] = 1.;
count++;
}
}
if ( count >= minNodesPerAggregate) {
nAggregates++;
count = 0;
}
}
}
// We have something which is under minNodesPerAggregate when
if (count != 0) {
#ifdef FIXME
// Can stick small aggregate with 0th aggregate?
if (nAggregates > 0) {
for (my_size_t i = 0; i < nVertices; i++) {
if ((vertex2AggId[i] == nAggregates) && (procWinner[i] == myPid)) {
vertex2AggId[i] = 0;
aggregates.SetIsRoot(i,false);
}
}
}
else {
Nsingle++;
nAggregates++;
}
#else
// Can stick small aggregate with 0th aggregate?
if (nAggregates > 0) {
for (my_size_t i = 0; i < nVertices; i++) {
// TW: This is not a real fix. This may produce ugly bad aggregates!
// I removed the procWinner[i] == myPid check. it makes no sense to me since
// it leaves vertex2AggId[i] == nAggregates -> crash in ComputeAggregateSizes().
// Maybe it's better to add the leftovers to the last generated agg on the current proc.
// The best solution would be to add them to the "next"/nearest aggregate, that may be
// on an other processor
if (vertex2AggId[i] == nAggregates) {
vertex2AggId[i] = nAggregates-1; //0;
aggregates.SetIsRoot(i,false);
}
}
}
else {
Nsingle++;
nAggregates++;
}
#endif
}
// views on distributed vectors are freed here.
}
//TODO JJH We want to skip this call
myWidget.ArbitrateAndCommunicate(*distWeights, aggregates, false);
if (IsPrint(Statistics1)) {
GO total_Nsingle=0; sumAll(graph.GetComm(), (GO)Nsingle, total_Nsingle);
GO total_Nleftover=0; sumAll(graph.GetComm(), (GO)Nleftover, total_Nleftover);
// GO total_aggs; sumAll(graph.GetComm(), (GO)nAggregates, total_aggs);
// GetOStream(Statistics1, 0) << "Phase 6 - total aggregates = " << total_aggs << std::endl;
GetOStream(Statistics1, 0) << "Phase 6 - leftovers = " << total_Nleftover << " and singletons = " << total_Nsingle << std::endl;
}
aggregates.SetNumAggregates(nAggregates);
} //AggregateLeftovers