BoundaryConditionsContainerImplementation.hpp

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*/
 
#ifndef _BOUNDARYCONDITIONSCONTAINERIMPLEMENTATION_HPP_
#define _BOUNDARYCONDITIONSCONTAINERIMPLEMENTATION_HPP_
 
#include "BoundaryConditionsContainer.hpp"
#include "ConstBoundaryCondition.hpp"
#include "DistributedVector.hpp"
#include "Exception.hpp"
#include "HeartEventHandler.hpp"
#include "PetscMatTools.hpp"
#include "PetscVecTools.hpp"
#include "ReplicatableVector.hpp"
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::BoundaryConditionsContainer(bool deleteConditions)
            : AbstractBoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>(deleteConditions)
{
    mLoadedFromArchive = false;
 
    for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
    {
        mpNeumannMap[index_of_unknown] = new std::map< const BoundaryElement<ELEMENT_DIM-1, SPACE_DIM> *, const AbstractBoundaryCondition<SPACE_DIM>*>;
 
        mAnyNonZeroNeumannConditionsForUnknown[index_of_unknown] = false;
        mLastNeumannCondition[index_of_unknown] = mpNeumannMap[index_of_unknown]->begin();
 
        mpPeriodicBcMap[index_of_unknown] = new std::map< const Node<SPACE_DIM> *, const Node<SPACE_DIM> * >;
    }
 
    // This zero boundary condition is only used in AddNeumannBoundaryCondition
    mpZeroBoundaryCondition = new ConstBoundaryCondition<SPACE_DIM>(0.0);
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::~BoundaryConditionsContainer()
{
    // Keep track of what boundary condition objects we've deleted
    std::set<const AbstractBoundaryCondition<SPACE_DIM>*> deleted_conditions;
    for (unsigned i=0; i<PROBLEM_DIM; i++)
    {
        NeumannMapIterator neumann_iterator = mpNeumannMap[i]->begin();
        while (neumann_iterator != mpNeumannMap[i]->end() )
        {
 
            if (deleted_conditions.count(neumann_iterator->second) == 0)
            {
                deleted_conditions.insert(neumann_iterator->second);
                //Leave the zero boundary condition until last
                if (neumann_iterator->second != mpZeroBoundaryCondition)
                {
                    if (this->mDeleteConditions)
                    {
                        delete neumann_iterator->second;
                    }
                }
            }
            neumann_iterator++;
        }
        delete(mpNeumannMap[i]);
        delete(mpPeriodicBcMap[i]);
    }
 
    delete mpZeroBoundaryCondition;
 
    if (this->mDeleteConditions)
    {
        this->DeleteDirichletBoundaryConditions(deleted_conditions);
    }
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::AddDirichletBoundaryCondition(const Node<SPACE_DIM>* pBoundaryNode,
                                        const AbstractBoundaryCondition<SPACE_DIM>* pBoundaryCondition,
                                        unsigned indexOfUnknown,
                                        bool checkIfBoundaryNode)
{
    assert(indexOfUnknown < PROBLEM_DIM);
    if (checkIfBoundaryNode)
    {
        assert(pBoundaryNode->IsBoundaryNode());
    }
 
    (*(this->mpDirichletMap[indexOfUnknown]))[pBoundaryNode] = pBoundaryCondition;
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::AddPeriodicBoundaryCondition(const Node<SPACE_DIM>* pNode1,
                                                                                                  const Node<SPACE_DIM>* pNode2)
{
    assert(pNode1->IsBoundaryNode());
    assert(pNode2->IsBoundaryNode());
 
    // will assume the periodic BC is to be applied to ALL unknowns, can't really imagine a
    // situation where this isn't going to be true. If necessary can easily change this method
    // to take in the index of the unknown
    for (unsigned i=0; i<PROBLEM_DIM; i++)
    {
        (*(this->mpPeriodicBcMap[i]))[pNode1] = pNode2;
    }
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::AddNeumannBoundaryCondition( const BoundaryElement<ELEMENT_DIM-1, SPACE_DIM> * pBoundaryElement,
                                      const AbstractBoundaryCondition<SPACE_DIM> * pBoundaryCondition,
                                      unsigned indexOfUnknown)
{
    assert(indexOfUnknown < PROBLEM_DIM);
 
    /*
     * If this condition is constant, we can test whether it is zero.
     * Otherwise we assume that this could be a non-zero boundary condition.
     */
    const ConstBoundaryCondition<SPACE_DIM>* p_const_cond = dynamic_cast<const ConstBoundaryCondition<SPACE_DIM>*>(pBoundaryCondition);
    if (p_const_cond)
    {
        if (p_const_cond->GetValue(pBoundaryElement->GetNode(0)->GetPoint()) != 0.0)
        {
            mAnyNonZeroNeumannConditionsForUnknown[indexOfUnknown] = true;
        }
    }
    else
    {
        mAnyNonZeroNeumannConditionsForUnknown[indexOfUnknown] = true;
    }
 
    for (unsigned unknown=0; unknown<PROBLEM_DIM; unknown++)
    {
        if (unknown == indexOfUnknown)
        {
            (*(mpNeumannMap[indexOfUnknown]))[pBoundaryElement] = pBoundaryCondition;
        }
        else
        {
            // If can't find pBoundaryElement in map[unknown]
            if (mpNeumannMap[unknown]->find(pBoundaryElement)==mpNeumannMap[unknown]->end())
            {
                // Add zero bc to other unknowns (so all maps are in sync)
                (*(mpNeumannMap[unknown]))[pBoundaryElement] = mpZeroBoundaryCondition;
            }
        }
    }
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::DefineZeroDirichletOnMeshBoundary(AbstractTetrahedralMesh<ELEMENT_DIM,SPACE_DIM>* pMesh,
                                           unsigned indexOfUnknown)
{
    this->DefineConstantDirichletOnMeshBoundary(pMesh, 0.0, indexOfUnknown);
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::DefineConstantDirichletOnMeshBoundary(AbstractTetrahedralMesh<ELEMENT_DIM,SPACE_DIM>* pMesh,
                                               double value,
                                               unsigned indexOfUnknown)
{
    assert(indexOfUnknown < PROBLEM_DIM);
    // In applying a condition to the boundary, we need to be sure that the boundary exists
    assert(PetscTools::ReplicateBool( pMesh->GetNumBoundaryNodes() > 0 ) );
 
    ConstBoundaryCondition<SPACE_DIM>* p_boundary_condition = new ConstBoundaryCondition<SPACE_DIM>(value);
 
    typename AbstractTetrahedralMesh<ELEMENT_DIM, SPACE_DIM>::BoundaryNodeIterator iter;
    iter = pMesh->GetBoundaryNodeIteratorBegin();
    while (iter != pMesh->GetBoundaryNodeIteratorEnd())
    {
        AddDirichletBoundaryCondition(*iter, p_boundary_condition, indexOfUnknown);
        iter++;
    }
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::DefineZeroNeumannOnMeshBoundary(AbstractTetrahedralMesh<ELEMENT_DIM,SPACE_DIM>* pMesh,
                                         unsigned indexOfUnknown)
{
    assert(indexOfUnknown < PROBLEM_DIM);
 
    // In applying a condition to the boundary, we need to be sure that the boundary exists
    assert(pMesh->GetNumBoundaryElements() > 0);
    ConstBoundaryCondition<SPACE_DIM>* p_zero_boundary_condition = new ConstBoundaryCondition<SPACE_DIM>( 0.0 );
 
    typename AbstractTetrahedralMesh<ELEMENT_DIM, SPACE_DIM>::BoundaryElementIterator iter;
    iter = pMesh->GetBoundaryElementIteratorBegin();
    while (iter != pMesh->GetBoundaryElementIteratorEnd())
    {
        AddNeumannBoundaryCondition(*iter, p_zero_boundary_condition, indexOfUnknown);
        iter++;
    }
 
    mAnyNonZeroNeumannConditionsForUnknown[indexOfUnknown] = false;
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::ApplyDirichletToLinearProblem(
        LinearSystem& rLinearSystem,
        bool applyToMatrix,
        bool applyToRhsVector)
{
    HeartEventHandler::BeginEvent(HeartEventHandler::DIRICHLET_BCS);
 
    if (applyToMatrix)
    {
        if (!this->HasDirichletBoundaryConditions())
        {
            // Short-circuit the replication if there are no conditions
            HeartEventHandler::EndEvent(HeartEventHandler::DIRICHLET_BCS);
            return;
        }
 
        bool matrix_is_symmetric = rLinearSystem.IsMatrixSymmetric();
 
        if (matrix_is_symmetric)
        {
            /*
             * Modifications to the RHS are stored in the Dirichlet boundary
             * conditions vector. This is done so that they can be reapplied
             * at each time step.
             * Make a new vector to store the Dirichlet offsets in.
             */
            Vec& r_bcs_vec = rLinearSystem.rGetDirichletBoundaryConditionsVector();
            if (!r_bcs_vec)
            {
                VecDuplicate(rLinearSystem.rGetRhsVector(), &r_bcs_vec);
            }
            PetscVecTools::Zero(r_bcs_vec);
            /*
             * If the matrix is symmetric, calls to GetMatrixRowDistributed()
             * require the matrix to be in assembled state. Otherwise we can
             * defer it.
             */
            rLinearSystem.AssembleFinalLinearSystem();
        }
 
        // Work out where we're setting Dirichlet boundary conditions *everywhere*, not just those locally known
        ReplicatableVector dirichlet_conditions(rLinearSystem.GetSize());
        unsigned lo, hi;
        {
            PetscInt lo_s, hi_s;
            rLinearSystem.GetOwnershipRange(lo_s, hi_s);
            lo = lo_s; hi = hi_s;
        }
        // Initialise all local entries to DBL_MAX, i.e. don't know if there's a condition
        for (unsigned i=lo; i<hi; i++)
        {
            dirichlet_conditions[i] = DBL_MAX;
        }
        // Now fill in the ones we know
        for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
        {
            this->mDirichIterator = this->mpDirichletMap[index_of_unknown]->begin();
 
            while (this->mDirichIterator != this->mpDirichletMap[index_of_unknown]->end() )
            {
                unsigned node_index = this->mDirichIterator->first->GetIndex();
                double value = this->mDirichIterator->second->GetValue(this->mDirichIterator->first->GetPoint());
                assert(value != DBL_MAX);
 
                unsigned row = PROBLEM_DIM*node_index + index_of_unknown;
                dirichlet_conditions[row] = value;
 
                this->mDirichIterator++;
            }
        }
 
        // And replicate
        dirichlet_conditions.Replicate(lo, hi);
 
        // Which rows have conditions?
        std::vector<unsigned> rows_to_zero;
        for (unsigned i=0; i<dirichlet_conditions.GetSize(); i++)
        {
            if (dirichlet_conditions[i] != DBL_MAX)
            {
                rows_to_zero.push_back(i);
            }
        }
 
        if (matrix_is_symmetric)
        {
            // Modify the matrix columns
            for (unsigned i=0; i<rows_to_zero.size(); i++)
            {
                unsigned col = rows_to_zero[i];
                double minus_value = -dirichlet_conditions[col];
 
                /*
                 * Get a vector which will store the column of the matrix (column d,
                 * where d is the index of the row (and column) to be altered for the
                 * boundary condition. Since the matrix is symmetric when get row
                 * number "col" and treat it as a column. PETSc uses compressed row
                 * format and therefore getting rows is far more efficient than getting
                 * columns.
                 */
                Vec matrix_col = rLinearSystem.GetMatrixRowDistributed(col);
 
                // Zero the correct entry of the column
                PetscVecTools::SetElement(matrix_col, col, 0.0);
 
                /*
                 * Set up the RHS Dirichlet boundary conditions vector.
                 * Assuming one boundary at the zeroth node (x_0 = value), this is equal to
                 *   -value*[0 a_21 a_31 .. a_N1]
                 * and will be added to the RHS.
                 */
                PetscVecTools::Finalise(matrix_col); //PETSc 3.19 doesn't like mixing "set" mode (above) with "add" mode
                PetscVecTools::AddScaledVector(rLinearSystem.rGetDirichletBoundaryConditionsVector(), matrix_col, minus_value);
                PetscTools::Destroy(matrix_col);
            }
        }
 
        /*
         * Now zero the appropriate rows and columns of the matrix. If the matrix
         * is symmetric we apply the boundary conditions in a way the symmetry isn't
         * lost (rows and columns). If not only the row is zeroed.
         */
        if (matrix_is_symmetric)
        {
            rLinearSystem.ZeroMatrixRowsAndColumnsWithValueOnDiagonal(rows_to_zero, 1.0);
        }
        else
        {
            rLinearSystem.ZeroMatrixRowsWithValueOnDiagonal(rows_to_zero, 1.0);
        }
    }
 
    if (applyToRhsVector)
    {
        // Apply the RHS boundary conditions modification if required.
        if (rLinearSystem.rGetDirichletBoundaryConditionsVector())
        {
            PetscVecTools::AddScaledVector(rLinearSystem.rGetRhsVector(), rLinearSystem.rGetDirichletBoundaryConditionsVector(), 1.0);
        }
 
        /*
         * Apply the actual boundary condition to the RHS, note this must be
         * done after the modification to the RHS vector.
         */
        for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
        {
            this->mDirichIterator = this->mpDirichletMap[index_of_unknown]->begin();
 
            while (this->mDirichIterator != this->mpDirichletMap[index_of_unknown]->end() )
            {
                unsigned node_index = this->mDirichIterator->first->GetIndex();
                double value = this->mDirichIterator->second->GetValue(this->mDirichIterator->first->GetPoint());
 
                unsigned row = PROBLEM_DIM*node_index + index_of_unknown;
 
                rLinearSystem.SetRhsVectorElement(row, value);
 
                this->mDirichIterator++;
            }
        }
    }
 
    HeartEventHandler::EndEvent(HeartEventHandler::DIRICHLET_BCS);
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::ApplyPeriodicBcsToLinearProblem(LinearSystem& rLinearSystem,
                                                                                                     bool applyToMatrix,
                                                                                                     bool applyToRhsVector)
{
    bool has_periodic_bcs = false;
    for (unsigned i=0; i<PROBLEM_DIM; i++)
    {
        if (!mpPeriodicBcMap[i]->empty())
        {
            has_periodic_bcs = true;
            break;
        }
    }
 
    EXCEPT_IF_NOT(has_periodic_bcs);
 
    if (applyToMatrix)
    {
        std::vector<unsigned> rows_to_zero;
        for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
        {
            for (typename std::map< const Node<SPACE_DIM> *, const Node<SPACE_DIM> * >::const_iterator iter = mpPeriodicBcMap[index_of_unknown]->begin();
                iter != mpPeriodicBcMap[index_of_unknown]->end();
                ++iter)
            {
                unsigned node_index_1 = iter->first->GetIndex();
                unsigned row_index_1 = PROBLEM_DIM*node_index_1 + index_of_unknown;
                rows_to_zero.push_back(row_index_1);
            }
        }
 
        rLinearSystem.ZeroMatrixRowsWithValueOnDiagonal(rows_to_zero, 1.0);
 
        for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
        {
            for (typename std::map< const Node<SPACE_DIM> *, const Node<SPACE_DIM> * >::const_iterator iter = mpPeriodicBcMap[index_of_unknown]->begin();
                iter != mpPeriodicBcMap[index_of_unknown]->end();
                ++iter)
            {
                unsigned node_index_1 = iter->first->GetIndex();
                unsigned node_index_2 = iter->second->GetIndex();
 
                unsigned mat_index1 = PROBLEM_DIM*node_index_1 + index_of_unknown;
                unsigned mat_index2 = PROBLEM_DIM*node_index_2 + index_of_unknown;
                PetscMatTools::SetElement(rLinearSystem.rGetLhsMatrix(), mat_index1, mat_index2, -1.0);
            }
        }
    }
 
    if (applyToRhsVector)
    {
        for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
        {
            for (typename std::map< const Node<SPACE_DIM> *, const Node<SPACE_DIM> * >::const_iterator iter = mpPeriodicBcMap[index_of_unknown]->begin();
                 iter != mpPeriodicBcMap[index_of_unknown]->end();
                 ++iter)
            {
                unsigned node_index = iter->first->GetIndex();
                unsigned row_index = PROBLEM_DIM*node_index + index_of_unknown;
                rLinearSystem.SetRhsVectorElement(row_index, 0.0);
            }
        }
    }
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::ApplyDirichletToNonlinearResidual(
        const Vec currentSolution,
        Vec residual,
        DistributedVectorFactory& rFactory)
{
    for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
    {
        this->mDirichIterator = this->mpDirichletMap[index_of_unknown]->begin();
 
        DistributedVector solution_distributed = rFactory.CreateDistributedVector(currentSolution, true /*Read-only*/);
        DistributedVector residual_distributed = rFactory.CreateDistributedVector(residual);
 
 
        while (this->mDirichIterator != this->mpDirichletMap[index_of_unknown]->end() )
        {
            DistributedVector::Stripe solution_stripe(solution_distributed, index_of_unknown);
            DistributedVector::Stripe residual_stripe(residual_distributed, index_of_unknown);
 
            unsigned node_index = this->mDirichIterator->first->GetIndex();
 
            double value = this->mDirichIterator->second->GetValue(this->mDirichIterator->first->GetPoint());
 
            if (solution_distributed.IsGlobalIndexLocal(node_index))
            {
                residual_stripe[node_index]=solution_stripe[node_index] - value;
            }
            this->mDirichIterator++;
        }
        // Don't restore the read-only one: solution_distributed.Restore();
        residual_distributed.Restore();
    }
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
void BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::ApplyDirichletToNonlinearJacobian(Mat jacobian)
{
    unsigned num_boundary_conditions = 0;
    for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
    {
        num_boundary_conditions += this->mpDirichletMap[index_of_unknown]->size();
    }
 
    std::vector<unsigned> rows_to_zero(num_boundary_conditions);
 
    unsigned counter=0;
    for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
    {
        this->mDirichIterator = this->mpDirichletMap[index_of_unknown]->begin();
 
        while (this->mDirichIterator != this->mpDirichletMap[index_of_unknown]->end() )
        {
            unsigned node_index = this->mDirichIterator->first->GetIndex();
            rows_to_zero[counter++] = PROBLEM_DIM*node_index + index_of_unknown;
            this->mDirichIterator++;
        }
    }
    PetscMatTools::Finalise(jacobian);
    PetscMatTools::ZeroRowsWithValueOnDiagonal(jacobian, rows_to_zero, 1.0);
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
bool BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::Validate(AbstractTetrahedralMesh<ELEMENT_DIM,SPACE_DIM>* pMesh)
{
    bool valid = true;
 
    for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
    {
        // Iterate over surface elements
        typename AbstractTetrahedralMesh<ELEMENT_DIM,SPACE_DIM>::BoundaryElementIterator elt_iter
        = pMesh->GetBoundaryElementIteratorBegin();
        while (valid && elt_iter != pMesh->GetBoundaryElementIteratorEnd())
        {
            if (!HasNeumannBoundaryCondition(*elt_iter, index_of_unknown))
            {
                // Check for Dirichlet conditions on this element's nodes
                for (unsigned i=0; i<(*elt_iter)->GetNumNodes(); i++)
                {
                    if (!this->HasDirichletBoundaryCondition((*elt_iter)->GetNode(i)))
                    {
                        valid = false;
                    }
                }
            }
            elt_iter++;
        }
    }
    return valid;
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
double BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::GetNeumannBCValue(const BoundaryElement<ELEMENT_DIM-1,SPACE_DIM>* pSurfaceElement,
                             const ChastePoint<SPACE_DIM>& rX,
                             unsigned indexOfUnknown)
{
    assert(indexOfUnknown < PROBLEM_DIM);
 
    // Did we see this condition on the last search we did?
    if (mLastNeumannCondition[indexOfUnknown] == mpNeumannMap[indexOfUnknown]->end() ||
        mLastNeumannCondition[indexOfUnknown]->first != pSurfaceElement)
    {
        mLastNeumannCondition[indexOfUnknown] = mpNeumannMap[indexOfUnknown]->find(pSurfaceElement);
    }
    if (mLastNeumannCondition[indexOfUnknown] == mpNeumannMap[indexOfUnknown]->end())
    {
        // No Neumann condition is equivalent to a zero Neumann condition
        return 0.0;
    }
    else
    {
        return mLastNeumannCondition[indexOfUnknown]->second->GetValue(rX);
    }
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
bool BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::HasNeumannBoundaryCondition(const BoundaryElement<ELEMENT_DIM-1,SPACE_DIM>* pSurfaceElement,
                                     unsigned indexOfUnknown)
{
    assert(indexOfUnknown < PROBLEM_DIM);
 
    mLastNeumannCondition[indexOfUnknown] = mpNeumannMap[indexOfUnknown]->find(pSurfaceElement);
 
    return (mLastNeumannCondition[indexOfUnknown] != mpNeumannMap[indexOfUnknown]->end());
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
bool BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::AnyNonZeroNeumannConditions()
{
    bool ret = false;
    for (unsigned index_of_unknown=0; index_of_unknown<PROBLEM_DIM; index_of_unknown++)
    {
        if (mAnyNonZeroNeumannConditionsForUnknown[index_of_unknown] == true)
        {
            ret = true;
        }
    }
    return ret;
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
typename BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::NeumannMapIterator BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::BeginNeumann()
{
    // [0] is ok as all maps will be in sync due to the way ApplyNeumannBoundaryCondition works
    return mpNeumannMap[0]->begin();
}
 
template<unsigned ELEMENT_DIM, unsigned SPACE_DIM, unsigned PROBLEM_DIM>
typename BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::NeumannMapIterator BoundaryConditionsContainer<ELEMENT_DIM,SPACE_DIM,PROBLEM_DIM>::EndNeumann()
{
    // [0] is ok as all maps will be in sync due to the way ApplyNeumannBoundaryCondition works
    return mpNeumannMap[0]->end();
}
 
#endif // _BOUNDARYCONDITIONSCONTAINERIMPLEMENTATION_HPP_