A global linear system. More...

#include <GlobalLinSysIterativeFull.h>

Inheritance diagram for Nektar::MultiRegions::GlobalLinSysIterativeFull:

Collaboration diagram for Nektar::MultiRegions::GlobalLinSysIterativeFull:

Public Member Functions
	GlobalLinSysIterativeFull (const GlobalLinSysKey &pLinSysKey, const boost::weak_ptr< ExpList > &pExpList, const boost::shared_ptr< AssemblyMap > &pLocToGloMap)
	Constructor for full direct matrix solve.
virtual	~GlobalLinSysIterativeFull ()
Public Member Functions inherited from Nektar::MultiRegions::GlobalLinSysIterative
	GlobalLinSysIterative (const GlobalLinSysKey &pKey, const boost::weak_ptr< ExpList > &pExpList, const boost::shared_ptr< AssemblyMap > &pLocToGloMap)
	Constructor for full direct matrix solve.
virtual	~GlobalLinSysIterative ()
Public Member Functions inherited from Nektar::MultiRegions::GlobalLinSys
	GlobalLinSys (const GlobalLinSysKey &pKey, const boost::weak_ptr< ExpList > &pExpList, const boost::shared_ptr< AssemblyMap > &pLocToGloMap)
	Constructor for full direct matrix solve.
virtual	~GlobalLinSys ()
const GlobalLinSysKey &	GetKey (void) const
	Returns the key associated with the system.
const boost::weak_ptr< ExpList > &	GetLocMat (void) const
void	InitObject ()
void	Initialise (const boost::shared_ptr< AssemblyMap > &pLocToGloMap)
void	Solve (const Array< OneD, const NekDouble > &in, Array< OneD, NekDouble > &out, const AssemblyMapSharedPtr &locToGloMap, const Array< OneD, const NekDouble > &dirForcing=NullNekDouble1DArray)
	Solve the linear system for given input and output vectors using a specified local to global map.
boost::shared_ptr< GlobalLinSys >	GetSharedThisPtr ()
	Returns a shared pointer to the current object.
int	GetNumBlocks ()
DNekScalMatSharedPtr	GetBlock (unsigned int n)
DNekScalBlkMatSharedPtr	GetStaticCondBlock (unsigned int n)
void	DropStaticCondBlock (unsigned int n)
void	SolveLinearSystem (const int pNumRows, const Array< OneD, const NekDouble > &pInput, Array< OneD, NekDouble > &pOutput, const AssemblyMapSharedPtr &locToGloMap, const int pNumDir=0)
	Solve the linear system for given input and output vectors.

Static Public Member Functions
static GlobalLinSysSharedPtr	create (const GlobalLinSysKey &pLinSysKey, const boost::weak_ptr< ExpList > &pExpList, const boost::shared_ptr< AssemblyMap > &pLocToGloMap)
	Creates an instance of this class.

Static Public Attributes
static std::string	className
	Name of class.

Private Member Functions
virtual void	v_Solve (const Array< OneD, const NekDouble > &in, Array< OneD, NekDouble > &out, const AssemblyMapSharedPtr &locToGloMap, const Array< OneD, const NekDouble > &dirForcing=NullNekDouble1DArray)
	Solve the linear system for given input and output vectors using a specified local to global map.
virtual void	v_DoMatrixMultiply (const Array< OneD, NekDouble > &pInput, Array< OneD, NekDouble > &pOutput)
virtual void	v_UniqueMap ()

Private Attributes
boost::shared_ptr< AssemblyMap >	m_locToGloMap

Additional Inherited Members
Protected Member Functions inherited from Nektar::MultiRegions::GlobalLinSysIterative
void	DoAconjugateProjection (const int pNumRows, const Array< OneD, const NekDouble > &pInput, Array< OneD, NekDouble > &pOutput, const AssemblyMapSharedPtr &locToGloMap, const int pNumDir)
	A-conjugate projection technique.
void	DoConjugateGradient (const int pNumRows, const Array< OneD, const NekDouble > &pInput, Array< OneD, NekDouble > &pOutput, const AssemblyMapSharedPtr &locToGloMap, const int pNumDir)
	Actual iterative solve.
void	Set_Rhs_Magnitude (const NekVector< NekDouble > &pIn)
virtual void	v_UniqueMap ()=0
Protected Attributes inherited from Nektar::MultiRegions::GlobalLinSysIterative
Array< OneD, int >	m_map
	Global to universal unique map.
NekDouble	m_tolerance
	Tolerance of iterative solver.
NekDouble	m_rhs_magnitude
	dot product of rhs to normalise stopping criterion
PreconditionerSharedPtr	m_precon
MultiRegions::PreconditionerType	m_precontype
int	m_totalIterations
bool	m_useProjection
	Whether to apply projection technique.
bool	m_root
	Provide verbose output and root if parallel.
bool	m_verbose
boost::circular_buffer< Array < OneD, NekDouble > >	m_prevLinSol
	Storage for solutions to previous linear problems.
int	m_numPrevSols
	Total counter of previous solutions.

Detailed Description

A global linear system.

Definition at line 48 of file GlobalLinSysIterativeFull.h.

Constructor & Destructor Documentation

Nektar::MultiRegions::GlobalLinSysIterativeFull::GlobalLinSysIterativeFull	(	const GlobalLinSysKey &	pKey,
		const boost::weak_ptr< ExpList > &	pExp,
		const boost::shared_ptr< AssemblyMap > &	pLocToGloMap
	)

Constructor for full direct matrix solve.

Parameters

pKey	Key specifying matrix to solve.
pExp	Shared pointer to expansion list for applying matrix evaluations.
pLocToGloMap	Local to global mapping.

Definition at line 69 of file GlobalLinSysIterativeFull.cpp.

References ASSERTL1, Nektar::MultiRegions::eIterativeFull, Nektar::MultiRegions::GlobalLinSysKey::GetGlobalSysSolnType(), and Nektar::MultiRegions::GlobalLinSys::m_linSysKey.

            : GlobalLinSys         (pKey, pExp, pLocToGloMap),
              GlobalLinSysIterative(pKey, pExp, pLocToGloMap)
        {
            ASSERTL1(m_linSysKey.GetGlobalSysSolnType()==eIterativeFull,
                     "This routine should only be used when using an Iterative "
                     "conjugate gradient matrix solve.");
        }

Nektar::MultiRegions::GlobalLinSysIterativeFull::~GlobalLinSysIterativeFull ( )

virtual

Definition at line 85 of file GlobalLinSysIterativeFull.cpp.

        {
        }

Member Function Documentation

static GlobalLinSysSharedPtr Nektar::MultiRegions::GlobalLinSysIterativeFull::create	(	const GlobalLinSysKey &	pLinSysKey,
		const boost::weak_ptr< ExpList > &	pExpList,
		const boost::shared_ptr< AssemblyMap > &	pLocToGloMap
	)

inlinestatic

Creates an instance of this class.

Definition at line 52 of file GlobalLinSysIterativeFull.h.

            {
                return MemoryManager<GlobalLinSysIterativeFull>
                    ::AllocateSharedPtr(pLinSysKey, pExpList, pLocToGloMap);
            }

void Nektar::MultiRegions::GlobalLinSysIterativeFull::v_DoMatrixMultiply	(	const Array< OneD, NekDouble > &	pInput,
		Array< OneD, NekDouble > &	pOutput
	)

privatevirtual

Definition at line 183 of file GlobalLinSysIterativeFull.cpp.

References ASSERTL0, Nektar::MultiRegions::eGlobal, Nektar::eWrapper, Nektar::MultiRegions::GlobalLinSys::m_expList, Nektar::MultiRegions::GlobalLinSys::m_linSysKey, m_locToGloMap, Vmath::Vadd(), and Vmath::Zero().

        {
            boost::shared_ptr<MultiRegions::ExpList> expList = m_expList.lock();
            // Perform matrix-vector operation A*d_i
            expList->GeneralMatrixOp(m_linSysKey,
                                     pInput, pOutput, eGlobal);
            // retrieve robin boundary condition information and apply robin
            // boundary conditions to the solution.
            const std::map<int, RobinBCInfoSharedPtr> vRobinBCInfo
                                                = expList->GetRobinBCInfo();
            if(vRobinBCInfo.size() > 0)
            {
                ASSERTL0(false,
                        "Robin boundaries not set up in IterativeFull solver.");
                int nGlobal = m_locToGloMap->GetNumGlobalCoeffs();
                int nLocal  = m_locToGloMap->GetNumLocalCoeffs();
                int nDir    = m_locToGloMap->GetNumGlobalDirBndCoeffs();
                int nNonDir = nGlobal - nDir;
                Array<OneD, NekDouble> robin_A(nGlobal, 0.0);
                Array<OneD, NekDouble> robin_l(nLocal,  0.0);
                Array<OneD, NekDouble> tmp;
                NekVector<NekDouble> robin(nNonDir,
                                           tmp = robin_A + nDir, eWrapper);
                // Operation: p_A = A * d_A
                // First map d_A to local solution
                m_locToGloMap->GlobalToLocal(pInput, robin_l);
                // Iterate over all the elements computing Robin BCs where
                // necessary
                for (int n = 0; n < expList->GetNumElmts(); ++n)
                {
                    int nel = expList->GetOffset_Elmt_Id(n);
                    int offset = expList->GetCoeff_Offset(n);
                    int ncoeffs = expList->GetExp(nel)->GetNcoeffs();
                    if(vRobinBCInfo.count(nel) != 0) // add robin mass matrix
                    {
                        RobinBCInfoSharedPtr rBC;
                        Array<OneD, NekDouble> tmp;
                        StdRegions::StdExpansionSharedPtr vExp = expList->GetExp(nel);
                        // add local matrix contribution
                        for(rBC = vRobinBCInfo.find(nel)->second;rBC; rBC = rBC->next)
                        {
                            vExp->AddRobinEdgeContribution(rBC->m_robinID,rBC->m_robinPrimitiveCoeffs, tmp = robin_l + offset);
                        }
                    }
                    else
                    {
                        Vmath::Zero(ncoeffs, &robin_l[offset], 1);
                    }
                }
                // Map local Robin contribution back to global coefficients
                m_locToGloMap->LocalToGlobal(robin_l, robin_A);
                // Add them to the output of the GeneralMatrixOp
                Vmath::Vadd(nGlobal, pOutput, 1, robin_A, 1, pOutput, 1);
            }
        }

void Nektar::MultiRegions::GlobalLinSysIterativeFull::v_Solve	(	const Array< OneD, const NekDouble > &	pInput,
		Array< OneD, NekDouble > &	pOutput,
		const AssemblyMapSharedPtr &	pLocToGloMap,
		const Array< OneD, const NekDouble > &	pDirForcing = `NullNekDouble1DArray`
	)

privatevirtual

Solve the linear system for given input and output vectors using a specified local to global map.

Solve a global linear system with Dirichlet forcing using a conjugate gradient method. This routine performs handling of the Dirichlet forcing terms and wraps the underlying iterative solver used for the remaining degrees of freedom.

Consider solving for $x$ , the matrix system $Ax=b$ , where $b$ is known. To enforce the Dirichlet terms we instead solve

$A(x-x_0) = b - Ax_0$

where $x_0$ is the Dirichlet forcing.

Parameters

pInput	RHS of linear system, .
pOutput	On input, values of dirichlet degrees of freedom with initial guess on other values. On output, the solution .
pLocToGloMap	Local to global mapping.
pDirForcing	Precalculated Dirichlet forcing.

Definition at line 109 of file GlobalLinSysIterativeFull.cpp.

References ASSERTL0, Nektar::MultiRegions::eGlobal, Nektar::MultiRegions::GlobalLinSys::m_expList, Nektar::MultiRegions::GlobalLinSys::m_linSysKey, m_locToGloMap, Nektar::LibUtilities::ReduceSum, Nektar::MultiRegions::GlobalLinSys::SolveLinearSystem(), Vmath::Vadd(), Vmath::Vcopy(), and Vmath::Vsub().

        {
            boost::shared_ptr<MultiRegions::ExpList> expList = m_expList.lock();
            bool vCG;
            if ((m_locToGloMap = boost::dynamic_pointer_cast<AssemblyMapCG>(
                     pLocToGloMap)))
            {
                vCG = true;
            }
            else if ((m_locToGloMap = boost::dynamic_pointer_cast<
                          AssemblyMapDG>(pLocToGloMap)))
            {
                vCG = false;
            }
            bool dirForcCalculated = (bool) pDirForcing.num_elements();
            int nDirDofs  = pLocToGloMap->GetNumGlobalDirBndCoeffs();
            int nGlobDofs = pLocToGloMap->GetNumGlobalCoeffs();
            int nDirTotal = nDirDofs;
            
            expList->GetComm()->AllReduce(nDirTotal, LibUtilities::ReduceSum);
            
            Array<OneD, NekDouble> tmp(nGlobDofs), tmp2;
            if(nDirTotal)
            {
                // calculate the Dirichlet forcing
                if(dirForcCalculated)
                {
                    Vmath::Vsub(nGlobDofs, pInput.get(), 1,
                                pDirForcing.get(), 1,
                                tmp.get(), 1);
                }
                else
                {
                    // Calculate the dirichlet forcing B_b (== X_b) and
                    // substract it from the rhs
                    expList->GeneralMatrixOp(
                        m_linSysKey, pOutput, tmp, eGlobal);
                    Vmath::Vsub(nGlobDofs, pInput.get(), 1,
                                           tmp.get(),    1,
                                           tmp.get(),    1);
                }
                if (vCG)
                {
                    Array<OneD, NekDouble> out(nGlobDofs,0.0);
                    // solve for perturbation from intiial guess in pOutput
                    SolveLinearSystem(
                        nGlobDofs, tmp, out, pLocToGloMap, nDirDofs);
                    Vmath::Vadd(nGlobDofs-nDirDofs,    &out    [nDirDofs], 1,
                                &pOutput[nDirDofs], 1, &pOutput[nDirDofs], 1);
                }
                else
                {
                    ASSERTL0(false, "Need DG solve if using Dir BCs");
                }
            }
            else
            {
                Vmath::Vcopy(nGlobDofs, pInput, 1, tmp, 1);
                SolveLinearSystem(nGlobDofs, tmp, pOutput, pLocToGloMap);
            }
        }

void Nektar::MultiRegions::GlobalLinSysIterativeFull::v_UniqueMap ( )

privatevirtual

Definition at line 251 of file GlobalLinSysIterativeFull.cpp.

References m_locToGloMap, and Nektar::MultiRegions::GlobalLinSysIterative::m_map.

        {
            m_map = m_locToGloMap->GetGlobalToUniversalMapUnique();
        }

Member Data Documentation

string Nektar::MultiRegions::GlobalLinSysIterativeFull::className

static

Initial value:

 GetGlobalLinSysFactory().RegisterCreatorFunction(
                    "IterativeFull",
                    GlobalLinSysIterativeFull::create,
                    "Iterative solver for full matrix system.")

Name of class.

Registers the class with the Factory.

Definition at line 63 of file GlobalLinSysIterativeFull.h.

boost::shared_ptr<AssemblyMap> Nektar::MultiRegions::GlobalLinSysIterativeFull::m_locToGloMap

private

Definition at line 76 of file GlobalLinSysIterativeFull.h.

Referenced by v_DoMatrixMultiply(), v_Solve(), and v_UniqueMap().

Public Member Functions

Static Public Member Functions

Static Public Attributes

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation