shared_ptr<const DiscreteBoundaryOperator<ResultType>>
assembleDenseBlock(
int rowStart, int rowEnd, int colStart, int colEnd,
const Space<BasisFunctionType> &testSpace,
const Space<BasisFunctionType> &trialSpace,
Fiber::LocalAssemblerForIntegralOperators<ResultType>& assembler,
const ParameterList ¶meterList) {
int numberOfRows = rowEnd - rowStart;
int numberOfColumns = colEnd - colStart;
if (colEnd > trialSpace.globalDofCount() ||
rowEnd > testSpace.globalDofCount() || colStart < 0 || rowStart < 0)
throw std::runtime_error("DenseGlobalBlockAssember::assembleWeakForm(): "
"Indices out of bounds");
Context<BasisFunctionType, ResultType> context(parameterList);
const AssemblyOptions &options = context.assemblyOptions();
// Create the operator's matrix
Matrix<ResultType> result(numberOfRows, numberOfColumns);
result.setZero();
std::unordered_map<int, std::vector<GlobalDofIndex>> trialIndexMap,
testIndexMap;
std::unordered_map<int, std::vector<BasisFunctionType>> trialDofWeights,
testDofWeights;
gatherElementInformation(colStart, colEnd, trialSpace, trialIndexMap,
trialDofWeights);
gatherElementInformation(rowStart, rowEnd, testSpace, testIndexMap,
testDofWeights);
std::vector<int> testIndices;
testIndices.reserve(testIndexMap.size());
for (const auto &p : testIndexMap)
testIndices.push_back(p.first);
typedef DenseWeakFormAssemblerLoopBody<BasisFunctionType, ResultType> Body;
typename Body::MutexType mutex;
{
Fiber::SerialBlasRegion region;
tbb::parallel_for_each(trialIndexMap.begin(), trialIndexMap.end(),
Body(rowStart, colStart, testIndices, testIndexMap,
trialIndexMap, testDofWeights, trialDofWeights,
assembler, result, mutex));
}
// Create and return a discrete operator represented by the matrix that
// has just been calculated
return shared_ptr<DiscreteBoundaryOperator<ResultType>>(
new DiscreteDenseBoundaryOperator<ResultType>(result));
}
Vector<ResultType> reallyCalculateProjections(
const Space<BasisFunctionType> &dualSpace,
Fiber::LocalAssemblerForGridFunctions<ResultType> &assembler,
const AssemblyOptions &options) {
// TODO: parallelise using TBB (the parameter options will then start be used)
// Get the grid's leaf view so that we can iterate over elements
const GridView &view = dualSpace.gridView();
const size_t elementCount = view.entityCount(0);
// Global DOF indices corresponding to local DOFs on elements
std::vector<std::vector<GlobalDofIndex>> testGlobalDofs(elementCount);
std::vector<std::vector<BasisFunctionType>> testLocalDofWeights(elementCount);
// Gather global DOF lists
const Mapper &mapper = view.elementMapper();
std::unique_ptr<EntityIterator<0>> it = view.entityIterator<0>();
while (!it->finished()) {
const Entity<0> &element = it->entity();
const int elementIndex = mapper.entityIndex(element);
dualSpace.getGlobalDofs(element, testGlobalDofs[elementIndex],
testLocalDofWeights[elementIndex]);
it->next();
}
// Make a vector of all element indices
std::vector<int> testIndices(elementCount);
for (size_t i = 0; i < elementCount; ++i)
testIndices[i] = i;
// Create the weak form's column vector
Vector<ResultType> result(dualSpace.globalDofCount());
result.setZero();
std::vector<Vector<ResultType>> localResult;
// Evaluate local weak forms
assembler.evaluateLocalWeakForms(testIndices, localResult);
// Loop over test indices
for (size_t testIndex = 0; testIndex < elementCount; ++testIndex)
// Add the integrals to appropriate entries in the global weak form
for (size_t testDof = 0; testDof < testGlobalDofs[testIndex].size();
++testDof) {
int testGlobalDof = testGlobalDofs[testIndex][testDof];
if (testGlobalDof >= 0) // if it's negative, it means that this
// local dof is constrained (not used)
result(testGlobalDof) +=
conj(testLocalDofWeights[testIndex][testDof]) *
localResult[testIndex](testDof);
}
// Return the vector of projections <phi_i, f>
return result;
}
std::auto_ptr<DiscreteBoundaryOperator<ResultType> >
DenseGlobalAssembler<BasisFunctionType, ResultType>::
assembleDetachedWeakForm(
const Space<BasisFunctionType>& testSpace,
const Space<BasisFunctionType>& trialSpace,
LocalAssemblerForIntegralOperators& assembler,
const Context<BasisFunctionType, ResultType>& context)
{
const AssemblyOptions& options = context.assemblyOptions();
// Global DOF indices corresponding to local DOFs on elements
std::vector<std::vector<GlobalDofIndex> > testGlobalDofs, trialGlobalDofs;
std::vector<std::vector<BasisFunctionType> > testLocalDofWeights,
trialLocalDofWeights;
gatherGlobalDofs(testSpace, testGlobalDofs, testLocalDofWeights);
if (&testSpace == &trialSpace) {
trialGlobalDofs = testGlobalDofs;
trialLocalDofWeights = testLocalDofWeights;
} else
gatherGlobalDofs(trialSpace, trialGlobalDofs, trialLocalDofWeights);
const size_t testElementCount = testGlobalDofs.size();
const size_t trialElementCount = trialGlobalDofs.size();
// Make a vector of all element indices
std::vector<int> testIndices(testElementCount);
for (int i = 0; i < testElementCount; ++i)
testIndices[i] = i;
// Create the operator's matrix
arma::Mat<ResultType> result(testSpace.globalDofCount(),
trialSpace.globalDofCount());
result.fill(0.);
typedef DenseWeakFormAssemblerLoopBody<BasisFunctionType, ResultType> Body;
typename Body::MutexType mutex;
const ParallelizationOptions& parallelOptions =
options.parallelizationOptions();
int maxThreadCount = 1;
if (!parallelOptions.isOpenClEnabled()) {
if (parallelOptions.maxThreadCount() == ParallelizationOptions::AUTO)
maxThreadCount = tbb::task_scheduler_init::automatic;
else
maxThreadCount = parallelOptions.maxThreadCount();
}
tbb::task_scheduler_init scheduler(maxThreadCount);
{
Fiber::SerialBlasRegion region;
tbb::parallel_for(tbb::blocked_range<size_t>(0, trialElementCount),
Body(testIndices, testGlobalDofs, trialGlobalDofs,
testLocalDofWeights, trialLocalDofWeights,
assembler, result, mutex));
}
//// Old serial code (TODO: decide whether to keep it behind e.g. #ifndef PARALLEL)
// std::vector<arma::Mat<ValueType> > localResult;
// // Loop over trial elements
// for (int trialIndex = 0; trialIndex < trialElementCount; ++trialIndex)
// {
// // Evaluate integrals over pairs of the current trial element and
// // all the test elements
// assembler.evaluateLocalWeakForms(TEST_TRIAL, testIndices, trialIndex,
// ALL_DOFS, localResult);
// // Loop over test indices
// for (int testIndex = 0; testIndex < testElementCount; ++testIndex)
// // Add the integrals to appropriate entries in the operator's matrix
// for (int trialDof = 0; trialDof < trialGlobalDofs[trialIndex].size(); ++trialDof)
// for (int testDof = 0; testDof < testGlobalDofs[testIndex].size(); ++testDof)
// result(testGlobalDofs[testIndex][testDof],
// trialGlobalDofs[trialIndex][trialDof]) +=
// localResult[testIndex](testDof, trialDof);
// }
// Create and return a discrete operator represented by the matrix that
// has just been calculated
return std::auto_ptr<DiscreteBoundaryOperator<ResultType> >(
new DiscreteDenseBoundaryOperator<ResultType>(result));
}
std::auto_ptr<DiscreteBoundaryOperator<ResultType> >
AcaGlobalAssembler<BasisFunctionType, ResultType>::assembleDetachedWeakForm(
const Space<BasisFunctionType>& testSpace,
const Space<BasisFunctionType>& trialSpace,
const std::vector<LocalAssembler*>& localAssemblers,
const std::vector<const DiscreteBndOp*>& sparseTermsToAdd,
const std::vector<ResultType>& denseTermsMultipliers,
const std::vector<ResultType>& sparseTermsMultipliers,
const AssemblyOptions& options,
int symmetry)
{
#ifdef WITH_AHMED
typedef AhmedDofWrapper<CoordinateType> AhmedDofType;
typedef ExtendedBemCluster<AhmedDofType> AhmedBemCluster;
typedef bemblcluster<AhmedDofType, AhmedDofType> AhmedBemBlcluster;
typedef DiscreteAcaBoundaryOperator<ResultType> DiscreteAcaLinOp;
const AcaOptions& acaOptions = options.acaOptions();
const bool indexWithGlobalDofs = acaOptions.globalAssemblyBeforeCompression;
const bool verbosityAtLeastDefault =
(options.verbosityLevel() >= VerbosityLevel::DEFAULT);
const bool verbosityAtLeastHigh =
(options.verbosityLevel() >= VerbosityLevel::HIGH);
// Currently we don't support Hermitian ACA operators. This is because we
// don't have the means to really test them -- we would need complex-valued
// basis functions for that. (Assembly of such a matrix would be very easy
// -- just change complex_sym from true to false in the call to apprx_sym()
// in AcaWeakFormAssemblerLoopBody::operator() -- but operations on
// symmetric/Hermitian matrices are not always trivial and we do need to be
// able to test them properly.)
bool symmetric = symmetry & SYMMETRIC;
if (symmetry & HERMITIAN && !(symmetry & SYMMETRIC) &&
verbosityAtLeastDefault)
std::cout << "Warning: assembly of non-symmetric Hermitian H-matrices "
"is not supported yet. A general H-matrix will be assembled"
<< std::endl;
#ifndef WITH_TRILINOS
if (!indexWithGlobalDofs)
throw std::runtime_error("AcaGlobalAssembler::assembleDetachedWeakForm(): "
"ACA assembly with globalAssemblyBeforeCompression "
"set to false requires BEM++ to be linked with "
"Trilinos");
#endif // WITH_TRILINOS
const size_t testDofCount = indexWithGlobalDofs ?
testSpace.globalDofCount() : testSpace.flatLocalDofCount();
const size_t trialDofCount = indexWithGlobalDofs ?
trialSpace.globalDofCount() : trialSpace.flatLocalDofCount();
if (symmetric && testDofCount != trialDofCount)
throw std::invalid_argument("AcaGlobalAssembler::assembleDetachedWeakForm(): "
"you cannot generate a symmetric weak form "
"using test and trial spaces with different "
"numbers of DOFs");
// o2p: map of original indices to permuted indices
// p2o: map of permuted indices to original indices
typedef ClusterConstructionHelper<BasisFunctionType> CCH;
shared_ptr<AhmedBemCluster> testClusterTree;
shared_ptr<IndexPermutation> test_o2pPermutation, test_p2oPermutation;
CCH::constructBemCluster(testSpace, indexWithGlobalDofs, acaOptions,
testClusterTree,
test_o2pPermutation, test_p2oPermutation);
shared_ptr<AhmedBemCluster> trialClusterTree;
shared_ptr<IndexPermutation> trial_o2pPermutation, trial_p2oPermutation;
if (symmetric || &testSpace == &trialSpace) {
trialClusterTree = testClusterTree;
trial_o2pPermutation = test_o2pPermutation;
trial_p2oPermutation = test_p2oPermutation;
} else
CCH::constructBemCluster(trialSpace, indexWithGlobalDofs, acaOptions,
trialClusterTree,
trial_o2pPermutation, trial_p2oPermutation);
// // Export VTK plots showing the disctribution of leaf cluster ids
// std::vector<unsigned int> testClusterIds;
// getClusterIds(*testClusterTree, test_p2oPermutation->permutedIndices(), testClusterIds);
// testSpace.dumpClusterIds("testClusterIds", testClusterIds,
// indexWithGlobalDofs ? GLOBAL_DOFS : FLAT_LOCAL_DOFS);
// std::vector<unsigned int> trialClusterIds;
// getClusterIds(*trialClusterTree, trial_p2oPermutation->permutedIndices(), trialClusterIds);
// trialSpace.dumpClusterIds("trialClusterIds", trialClusterIds,
// indexWithGlobalDofs ? GLOBAL_DOFS : FLAT_LOCAL_DOFS);
if (verbosityAtLeastHigh)
std::cout << "Test cluster count: " << testClusterTree->getncl()
<< "\nTrial cluster count: " << trialClusterTree->getncl()
<< std::endl;
unsigned int blockCount = 0;
shared_ptr<AhmedBemBlcluster> bemBlclusterTree(
CCH::constructBemBlockCluster(acaOptions, symmetric,
*testClusterTree, *trialClusterTree,
blockCount).release());
if (verbosityAtLeastHigh)
std::cout << "Mblock count: " << blockCount << std::endl;
std::vector<unsigned int> p2oTestDofs =
test_p2oPermutation->permutedIndices();
std::vector<unsigned int> p2oTrialDofs =
trial_p2oPermutation->permutedIndices();
WeakFormAcaAssemblyHelper<BasisFunctionType, ResultType>
helper(testSpace, trialSpace, p2oTestDofs, p2oTrialDofs,
localAssemblers, sparseTermsToAdd,
denseTermsMultipliers, sparseTermsMultipliers, options);
typedef mblock<typename AhmedTypeTraits<ResultType>::Type> AhmedMblock;
boost::shared_array<AhmedMblock*> blocks =
allocateAhmedMblockArray<ResultType>(bemBlclusterTree.get());
// matgen_sqntl(helper, AhmedBemBlclusterTree.get(), AhmedBemBlclusterTree.get(),
// acaOptions.recompress, acaOptions.eps,
// acaOptions.maximumRank, blocks.get());
// matgen_omp(helper, blockCount, AhmedBemBlclusterTree.get(),
// acaOptions.eps, acaOptions.maximumRank, blocks.get());
// // Dump mblocks
// const int mblockCount = AhmedBemBlclusterTree->nleaves();
// for (int i = 0; i < mblockCount; ++i)
// if (blocks[i]->isdns())
// {
// char buffer[1024];
// sprintf(buffer, "mblock-dns-%d-%d.txt",
// blocks[i]->getn1(), blocks[i]->getn2());
// arma::Col<ResultType> block((ResultType*)blocks[i]->getdata(),
// blocks[i]->nvals());
// arma::diskio::save_raw_ascii(block, buffer);
// }
// else
// {
// char buffer[1024];
// sprintf(buffer, "mblock-lwr-%d-%d.txt",
// blocks[i]->getn1(), blocks[i]->getn2());
// arma::Col<ResultType> block((ResultType*)blocks[i]->getdata(),
// blocks[i]->nvals());
// arma::diskio::save_raw_ascii(block, buffer);
// }
AhmedLeafClusterArray leafClusters(bemBlclusterTree.get());
leafClusters.sortAccordingToClusterSize();
const size_t leafClusterCount = leafClusters.size();
const ParallelizationOptions& parallelOptions =
options.parallelizationOptions();
int maxThreadCount = 1;
if (!parallelOptions.isOpenClEnabled())
{
if (parallelOptions.maxThreadCount() == ParallelizationOptions::AUTO)
maxThreadCount = tbb::task_scheduler_init::automatic;
else
maxThreadCount = parallelOptions.maxThreadCount();
}
tbb::task_scheduler_init scheduler(maxThreadCount);
tbb::atomic<size_t> done;
done = 0;
std::vector<ChunkStatistics> chunkStats(leafClusterCount);
// typedef AcaWeakFormAssemblerLoopBody<BasisFunctionType, ResultType> Body;
// // std::cout << "Loop start" << std::endl;
// tbb::tick_count loopStart = tbb::tick_count::now();
// // tbb::parallel_for(tbb::blocked_range<size_t>(0, leafClusterCount),
// // Body(helper, leafClusters, blocks, acaOptions, done
// // , chunkStats));
// tbb::parallel_for(ScatteredRange(0, leafClusterCount),
// Body(helper, leafClusters, blocks, acaOptions, done
// , chunkStats));
// tbb::tick_count loopEnd = tbb::tick_count::now();
// // std::cout << "Loop end" << std::endl;
typedef AcaWeakFormAssemblerLoopBody<BasisFunctionType, ResultType> Body;
typename Body::LeafClusterIndexQueue leafClusterIndexQueue;
for (size_t i = 0; i < leafClusterCount; ++i)
leafClusterIndexQueue.push(i);
if (verbosityAtLeastDefault)
std::cout << "About to start the ACA assembly loop" << std::endl;
tbb::tick_count loopStart = tbb::tick_count::now();
{
Fiber::SerialBlasRegion region; // if possible, ensure that BLAS is single-threaded
tbb::parallel_for(tbb::blocked_range<size_t>(0, leafClusterCount),
Body(helper, leafClusters, blocks, acaOptions, done,
verbosityAtLeastDefault,
leafClusterIndexQueue, symmetric, chunkStats));
}
tbb::tick_count loopEnd = tbb::tick_count::now();
if (verbosityAtLeastDefault) {
std::cout << "\n"; // the progress bar doesn't print the final \n
std::cout << "ACA loop took " << (loopEnd - loopStart).seconds() << " s"
<< std::endl;
}
// TODO: parallelise!
if (acaOptions.recompress) {
if (verbosityAtLeastDefault)
std::cout << "About to start ACA agglomeration" << std::endl;
agglH(bemBlclusterTree.get(), blocks.get(),
acaOptions.eps, acaOptions.maximumRank);
if (verbosityAtLeastDefault)
std::cout << "Agglomeration finished" << std::endl;
}
// // Dump timing data of individual chunks
// std::cout << "\nChunks:\n";
// for (int i = 0; i < leafClusterCount; ++i)
// if (chunkStats[i].valid) {
// int blockIndex = leafClusters[i]->getidx();
// std::cout << chunkStats[i].chunkStart << "\t"
// << chunkStats[i].chunkSize << "\t"
// << (chunkStats[i].startTime - loopStart).seconds() << "\t"
// << (chunkStats[i].endTime - loopStart).seconds() << "\t"
// << (chunkStats[i].endTime - chunkStats[i].startTime).seconds() << "\t"
// << blocks[blockIndex]->getn1() << "\t"
// << blocks[blockIndex]->getn2() << "\t"
// << blocks[blockIndex]->islwr() << "\t"
// << (blocks[blockIndex]->islwr() ? blocks[blockIndex]->rank() : 0) << "\n";
// }
{
size_t origMemory = sizeof(ResultType) * testDofCount * trialDofCount;
size_t ahmedMemory = sizeH(bemBlclusterTree.get(), blocks.get());
int maximumRank = Hmax_rank(bemBlclusterTree.get(), blocks.get());
if (verbosityAtLeastDefault)
std::cout << "\nNeeded storage: "
<< ahmedMemory / 1024. / 1024. << " MB.\n"
<< "Without approximation: "
<< origMemory / 1024. / 1024. << " MB.\n"
<< "Compressed to "
<< (100. * ahmedMemory) / origMemory << "%.\n"
<< "Maximum rank: " << maximumRank << ".\n"
<< std::endl;
if (acaOptions.outputPostscript) {
if (verbosityAtLeastDefault)
std::cout << "Writing matrix partition ..." << std::flush;
std::ofstream os(acaOptions.outputFname.c_str());
if (symmetric) // seems valid also for Hermitian matrices
psoutputHeH(os, bemBlclusterTree.get(), testDofCount, blocks.get());
else
psoutputGeH(os, bemBlclusterTree.get(), testDofCount, blocks.get());
os.close();
if (verbosityAtLeastDefault)
std::cout << " done." << std::endl;
}
}
int outSymmetry = NO_SYMMETRY;
if (symmetric) {
outSymmetry = SYMMETRIC;
if (!boost::is_complex<ResultType>())
outSymmetry |= HERMITIAN;
}
std::auto_ptr<DiscreteAcaLinOp> acaOp(
new DiscreteAcaLinOp(testDofCount, trialDofCount,
acaOptions.eps,
acaOptions.maximumRank,
outSymmetry,
bemBlclusterTree, blocks,
*trial_o2pPermutation,
*test_o2pPermutation,
parallelOptions));
std::auto_ptr<DiscreteBndOp> result;
if (indexWithGlobalDofs)
result = acaOp;
else {
#ifdef WITH_TRILINOS
// without Trilinos, this code will never be reached -- an exception
// will be thrown earlier in this function
typedef DiscreteBoundaryOperatorComposition<ResultType> DiscreteBndOpComp;
shared_ptr<DiscreteBndOp> acaOpShared(acaOp.release());
shared_ptr<DiscreteBndOp> trialGlobalToLocal =
constructOperatorMappingGlobalToFlatLocalDofs<
BasisFunctionType, ResultType>(trialSpace);
shared_ptr<DiscreteBndOp> testLocalToGlobal =
constructOperatorMappingFlatLocalToGlobalDofs<
BasisFunctionType, ResultType>(testSpace);
shared_ptr<DiscreteBndOp> tmp(
new DiscreteBndOpComp(acaOpShared, trialGlobalToLocal));
result.reset(new DiscreteBndOpComp(testLocalToGlobal, tmp));
#endif // WITH_TRILINOS
}
return result;
#else // without Ahmed
throw std::runtime_error("AcaGlobalAssembler::assembleDetachedWeakForm(): "
"To enable assembly in ACA mode, recompile BEM++ "
"with the symbol WITH_AHMED defined.");
#endif // WITH_AHMED
}