//==============================================================================
int Ifpack_CrsRiluk::BlockGraph2PointGraph(const Epetra_CrsGraph & BG, Epetra_CrsGraph & PG, bool Upper) {
if (!BG.IndicesAreLocal()) {EPETRA_CHK_ERR(-1);} // Must have done FillComplete on BG
int * ColFirstPointInElementList = BG.RowMap().FirstPointInElementList();
int * ColElementSizeList = BG.RowMap().ElementSizeList();
if (BG.Importer()!=0) {
ColFirstPointInElementList = BG.ImportMap().FirstPointInElementList();
ColElementSizeList = BG.ImportMap().ElementSizeList();
}
int Length = (BG.MaxNumIndices()+1) * BG.ImportMap().MaxMyElementSize();
vector<int> tmpIndices(Length);
int BlockRow, BlockOffset, NumEntries;
int NumBlockEntries;
int * BlockIndices;
int NumMyRows_tmp = PG.NumMyRows();
for (int i=0; i<NumMyRows_tmp; i++) {
EPETRA_CHK_ERR(BG.RowMap().FindLocalElementID(i, BlockRow, BlockOffset));
EPETRA_CHK_ERR(BG.ExtractMyRowView(BlockRow, NumBlockEntries, BlockIndices));
int * ptr = &tmpIndices[0]; // Set pointer to beginning of buffer
int RowDim = BG.RowMap().ElementSize(BlockRow);
NumEntries = 0;
// This next line make sure that the off-diagonal entries in the block diagonal of the
// original block entry matrix are included in the nonzero pattern of the point graph
if (Upper) {
int jstart = i+1;
int jstop = EPETRA_MIN(NumMyRows_tmp,i+RowDim-BlockOffset);
for (int j= jstart; j< jstop; j++) {*ptr++ = j; NumEntries++;}
}
for (int j=0; j<NumBlockEntries; j++) {
int ColDim = ColElementSizeList[BlockIndices[j]];
NumEntries += ColDim;
assert(NumEntries<=Length); // Sanity test
int Index = ColFirstPointInElementList[BlockIndices[j]];
for (int k=0; k < ColDim; k++) *ptr++ = Index++;
}
// This next line make sure that the off-diagonal entries in the block diagonal of the
// original block entry matrix are included in the nonzero pattern of the point graph
if (!Upper) {
int jstart = EPETRA_MAX(0,i-RowDim+1);
int jstop = i;
for (int j = jstart; j < jstop; j++) {*ptr++ = j; NumEntries++;}
}
EPETRA_CHK_ERR(PG.InsertMyIndices(i, NumEntries, &tmpIndices[0]));
}
SetAllocated(true);
return(0);
}
//============================================================================
Epetra_CrsGraph* Ifpack_CreateOverlappingCrsMatrix(const Epetra_CrsGraph* Graph,
const int OverlappingLevel)
{
if (OverlappingLevel == 0)
return(0); // All done
if (Graph->Comm().NumProc() == 1)
return(0); // All done
Epetra_CrsGraph* OverlappingGraph;
Epetra_BlockMap* OverlappingMap;
OverlappingGraph = const_cast<Epetra_CrsGraph*>(Graph);
OverlappingMap = const_cast<Epetra_BlockMap*>(&(Graph->RowMap()));
Epetra_CrsGraph* OldGraph;
Epetra_BlockMap* OldMap;
const Epetra_BlockMap* DomainMap = &(Graph->DomainMap());
const Epetra_BlockMap* RangeMap = &(Graph->RangeMap());
for (int level = 1; level <= OverlappingLevel ; ++level) {
OldGraph = OverlappingGraph;
OldMap = OverlappingMap;
Epetra_Import* OverlappingImporter;
OverlappingImporter = const_cast<Epetra_Import*>(OldGraph->Importer());
OverlappingMap = new Epetra_BlockMap(OverlappingImporter->TargetMap());
if (level < OverlappingLevel)
OverlappingGraph = new Epetra_CrsGraph(Copy, *OverlappingMap, 0);
else
// On last iteration, we want to filter out all columns except
// those that correspond
// to rows in the graph. This assures that our matrix is square
OverlappingGraph = new Epetra_CrsGraph(Copy, *OverlappingMap,
*OverlappingMap, 0);
OverlappingGraph->Import(*OldGraph, *OverlappingImporter, Insert);
if (level < OverlappingLevel)
OverlappingGraph->FillComplete(*DomainMap, *RangeMap);
else {
// Copy last OverlapImporter because we will use it later
OverlappingImporter = new Epetra_Import(*OverlappingMap, *DomainMap);
OverlappingGraph->FillComplete(*DomainMap, *RangeMap);
}
if (level > 1) {
delete OldGraph;
delete OldMap;
}
delete OverlappingMap;
OverlappingGraph->FillComplete();
}
return(OverlappingGraph);
}
