test_bdf_2d.cpp

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/*
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    Copyright (C) 2004, 2005, 2007 EPFL, Politecnico di Milano, INRIA
    Copyright (C) 2010 EPFL, Politecnico di Milano, Emory University

    This file is part of LifeV.

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/*!
    @file
    @brief

    @author Umberto Villa <uvilla@emory.edu>
    @date 14-04-2010
 */


// ===================================================
//! Includes
// ===================================================

#include <Epetra_ConfigDefs.h>
#ifdef EPETRA_MPI
#include <mpi.h>
#include <Epetra_MpiComm.h>
#else
#include <Epetra_SerialComm.h>
#endif


#include <lifev/core/array/MapEpetra.hpp>
#include <lifev/core/mesh/MeshData.hpp>
#include <lifev/core/mesh/MeshPartitioner.hpp>
#include <lifev/core/algorithm/SolverAztecOO.hpp>
#include <lifev/core/algorithm/LinearSolver.hpp>
#include <lifev/core/fem/Assembly.hpp>
#include <lifev/core/fem/AssemblyElemental.hpp>
#include <lifev/core/fem/BCManage.hpp>
#include <lifev/core/fem/FESpace.hpp>
#include <lifev/core/fem/TimeAdvanceBDFVariableStep.hpp>

#include <lifev/core/algorithm/PreconditionerIfpack.hpp>
#include <lifev/core/algorithm/PreconditionerML.hpp>

#include <lifev/core/filter/Exporter.hpp>
#include <lifev/core/filter/ExporterEmpty.hpp>
#include <lifev/core/filter/ExporterEnsight.hpp>
#include <lifev/core/filter/ExporterHDF5.hpp>
#include <lifev/core/mesh/RegionMesh.hpp>

#include <Teuchos_ParameterList.hpp>
#include <Teuchos_XMLParameterListHelpers.hpp>
#include <Teuchos_RCP.hpp>

#include "ud_functions.hpp"
#include "test_bdf.hpp"

// ===================================================
//! Namespaces & Define
// ===================================================
using namespace LifeV;

const int TOP = 3;
const int BOTTOM = 1;
const int LEFT = 1;
const int RIGHT = 2;

typedef RegionMesh<LinearTriangle> regionMesh;

const std::string discretization_section = "space_discretization";

// ===================================================
//! Private Members
// ===================================================
struct test_bdf::Private
{
    Private()
    {
    }

    typedef std::function < Real (Real const&, Real const&, Real const&,
                                    Real const&, ID const&) > fct_type;

    std::string data_file_name;
    std::shared_ptr<Epetra_Comm> comm;
    Real errorNorm;

};

// ===================================================
//! Constructors
// ===================================================
test_bdf::test_bdf (int argc, char** argv) :
    Members (new Private)
{
    GetPot command_line (argc, argv);
    const std::string data_file_name =
        command_line.follow ("data_2d", 2, "-f", "--file");
    GetPot dataFile (data_file_name);

    Members->data_file_name = data_file_name;

#ifdef EPETRA_MPI
    std::cout << "Epetra Initialization" << std::endl;
    Members->comm.reset (new Epetra_MpiComm (MPI_COMM_WORLD) );
#else
    Members->comm.reset (new Epetra_SerialComm() );
#endif
}

// ===================================================
//! Methods
// ===================================================
void test_bdf::run()
{
    //Useful typedef
    typedef VectorEpetra vector_Type;
    typedef std::shared_ptr<vector_Type> vectorPtr_Type;

    typedef LifeV::Preconditioner basePrec_Type;
    typedef std::shared_ptr<basePrec_Type> basePrecPtr_Type;
    typedef LifeV::PreconditionerIfpack prec_Type;
    typedef std::shared_ptr<prec_Type> precPtr_Type;

    // Reading from data file
    GetPot dataFile (Members->data_file_name.c_str() );
    // Select Pid(0) to write on std output
    bool verbose = (Members->comm->MyPID() == 0);

    if (verbose)
    {
        std::cout << "The BDF Solver" << std::flush;
    }

    //the forcing term
    SourceFct_2d sf;
    // the boundary conditions
    BCFunctionBase g_Ess (AnalyticalSol_2d::u);

    BCHandler bc;

    bc.addBC ("Top", TOP, Essential, Full, g_Ess, 1);
    bc.addBC ("Bottom", BOTTOM, Essential, Full, g_Ess, 1);
    bc.addBC ("Left", LEFT, Essential, Full, g_Ess, 1);
    bc.addBC ("Right", RIGHT, Essential, Full, g_Ess, 1);
    //=============================================================================
    //Mesh stuff
    Members->comm->Barrier();
    MeshData meshData (dataFile, ("bdf/" + discretization_section).c_str() );
    std::shared_ptr<regionMesh> fullMeshPtr ( new regionMesh ( Members->comm ) );
    readMesh (*fullMeshPtr, meshData);
    std::shared_ptr<regionMesh> meshPtr;
    {
        MeshPartitioner<regionMesh> meshPart ( fullMeshPtr, Members->comm );
        meshPtr = meshPart.meshPartition();
    }

    //=============================================================================
    //finite element space of the solution
    std::shared_ptr<FESpace<regionMesh, MapEpetra> > feSpacePtr (
        new FESpace<regionMesh, MapEpetra> (
            meshPtr, dataFile ( ("bdf/" + discretization_section + "/order").c_str(), "P2"), 1, Members->comm) );

    if (verbose)
        std::cout << "  Number of unknowns : "
                  << feSpacePtr->map().map (Unique)->NumGlobalElements()
                  << std::endl;

    bc.bcUpdate (* (feSpacePtr->mesh() ), feSpacePtr->feBd(), feSpacePtr->dof() );

    //=============================================================================
    //Fe Matrices and vectors
    MatrixElemental elmat (feSpacePtr->fe().nbFEDof(), 1, 1); //local matrix
    MatrixEpetra<double> matM (feSpacePtr->map() ); //mass matrix
    std::shared_ptr<MatrixEpetra<double> > matA_ptr (
        new MatrixEpetra<double> (feSpacePtr->map() ) ); //stiff matrix
    std::shared_ptr<VectorEpetra> u ( new VectorEpetra (feSpacePtr->map(), Unique) ); // solution vector
    std::shared_ptr<VectorEpetra> f ( new VectorEpetra (feSpacePtr->map(), Unique) ); // forcing term vector

    LifeChrono chrono;
    //Assembling Matrix M
    Members->comm->Barrier();
    chrono.start();
    for (UInt iVol = 0; iVol < feSpacePtr->mesh()->numElements(); iVol++)
    {
        feSpacePtr->fe().updateJac (feSpacePtr->mesh()->element (iVol) );
        elmat.zero();
        AssemblyElemental::mass (1., elmat, feSpacePtr->fe(), 0, 0);
        assembleMatrix (matM, elmat, feSpacePtr->fe(), feSpacePtr->fe(), feSpacePtr->dof(),
                        feSpacePtr->dof(), 0, 0, 0, 0);
    }
    matM.globalAssemble();
    Members->comm->Barrier();
    chrono.stop();
    if (verbose)
        std::cout << "\n \n -- Mass matrix assembling time = " << chrono.diff() << std::endl
                  << std::endl;

    // ==========================================
    // Definition of the time integration stuff
    // ==========================================
    Real Tfin = dataFile ("bdf/endtime", 10.0);
    Real delta_t = dataFile ("bdf/timestep", 0.5);
    Real t0 = 1.;
    UInt ord_bdf = dataFile ("bdf/order", 3);
    TimeAdvanceBDFVariableStep<VectorEpetra> bdf;
    bdf.setup (ord_bdf);

    //Initialization
    bdf.setInitialCondition<Real (*) (Real, Real, Real, Real, UInt), FESpace<regionMesh, MapEpetra> > (AnalyticalSol_2d::u, *u, *feSpacePtr, t0, delta_t);

    if (verbose)
    {
        bdf.showMe();
    }
    Members->comm->Barrier();

    //===================================================
    // post processing setup
    std::shared_ptr<Exporter<regionMesh> > exporter;
    std::string const exporterType =  dataFile ( "exporter/type", "hdf5");

#ifdef HAVE_HDF5
    if (exporterType.compare ("hdf5") == 0)
    {
        exporter.reset ( new ExporterHDF5<regionMesh > ( dataFile, "bdf_test" ) );
    }
    else
#endif
    {
        if (exporterType.compare ("none") == 0)
        {
            exporter.reset ( new ExporterEmpty<regionMesh > ( dataFile, meshPtr, "bdf_test", Members->comm->MyPID() ) );
        }
        else
        {
            exporter.reset ( new ExporterEnsight<regionMesh > ( dataFile, meshPtr, "bdf_test", Members->comm->MyPID() ) );
        }
    }

    exporter->setPostDir ( "./" );
    exporter->setMeshProcId ( meshPtr, Members->comm->MyPID() );

    std::shared_ptr<VectorEpetra> u_display_ptr (new VectorEpetra (
                                                       feSpacePtr->map(), exporter->mapType() ) );
    exporter->addVariable (ExporterData<regionMesh >::ScalarField, "u", feSpacePtr,
                           u_display_ptr, UInt (0) );
    *u_display_ptr = *u;
    exporter->postProcess (0);


    //===================================================
    //Definition of the linear solver
    LinearSolver linearSolver;

    Teuchos::RCP< Teuchos::ParameterList > belosList = Teuchos::rcp ( new Teuchos::ParameterList );
    belosList = Teuchos::getParametersFromXmlFile ( "SolverParamList.xml" );

    linearSolver.setCommunicator ( Members->comm );
    linearSolver.setParameters ( *belosList );

    prec_Type* precRawPtr;
    basePrecPtr_Type precPtr;
    precRawPtr = new prec_Type;
    precRawPtr->setDataFromGetPot ( dataFile, "bdf/prec" );
    precPtr.reset ( precRawPtr );
    linearSolver.setPreconditioner ( precPtr );

    //===================================================
    // TIME LOOP
    //===================================================

    matA_ptr.reset (new MatrixEpetra<double> (feSpacePtr->map() ) );

    for (Real t = t0 + delta_t; t <= Tfin; t += delta_t)
    {
        Members->comm->Barrier();
        if (verbose)
        {
            std::cout << "Now we are at time " << t << std::endl;
        }

        chrono.start();
        //Assemble A
        Real coeff = bdf.coefficientDerivative (0) / delta_t;
        Real visc = nu (t);
        Real s = sigma (t);
        for (UInt i = 0; i < feSpacePtr->mesh()->numElements(); i++)
        {
            feSpacePtr->fe().updateFirstDerivQuadPt (feSpacePtr->mesh()->element (i) );
            elmat.zero();
            AssemblyElemental::mass (coeff + s, elmat, feSpacePtr->fe() );
            AssemblyElemental::stiff (visc, elmat, feSpacePtr->fe() );
            assembleMatrix (*matA_ptr, elmat, feSpacePtr->fe(), feSpacePtr->fe(),
                            feSpacePtr->dof(), feSpacePtr->dof(), 0, 0, 0, 0);
        }

        chrono.stop();
        if (verbose)
        {
            std::cout << "A has been constructed in " << chrono.diff() << "s." << std::endl;
        }

        // Handling of the right hand side
        *f = (matM * bdf.rhsContribution() );    //f = M*\sum_{i=1}^{orderBdf} \alpha_i u_{n-i}
        feSpacePtr->l2ScalarProduct (sf, *f, t); //f +=\int_\Omega{ volumeForces *v dV}
        Members->comm->Barrier();

        // Treatment of the Boundary conditions
        if (verbose)
        {
            std::cout << "*** BC Management: " << std::endl;
        }
        Real tgv = 1.;
        chrono.start();
        bcManage (*matA_ptr, *f, *feSpacePtr->mesh(), feSpacePtr->dof(), bc, feSpacePtr->feBd(), tgv, t);
        matA_ptr->globalAssemble();
        chrono.stop();
        if (verbose)
        {
            std::cout << chrono.diff() << "s." << std::endl;
        }

        //Set Up the linear system
        Members->comm->Barrier();
        chrono.start();

        linearSolver.setOperator ( matA_ptr );
        linearSolver.setReusePreconditioner (false);
        linearSolver.setRightHandSide ( f );
        linearSolver.solve ( u );

        bdf.shiftRight (*u);

        if (verbose)
            std::cout << "*** Solution computed in " << chrono.diff() << "s."
                 << std::endl;

        Members->comm->Barrier();

        // Error in the L2
        vector_Type uComputed (*u, Repeated);

        Real L2_Error, L2_RelError;

        L2_Error = feSpacePtr->l2Error (AnalyticalSol_2d::u, uComputed, t, &L2_RelError);

        if (verbose)
            std::cout << "Error Norm L2: " << L2_Error
                      << "\nRelative Error Norm L2: " << L2_RelError << std::endl;

        Members->errorNorm = L2_Error;

        //transfer the solution at time t.
        *u_display_ptr = *u;

        matA_ptr->zero();

        exporter->postProcess (t);
    }



}

bool test_bdf::check()
{
    // Reading from data file
    GetPot dataFile (Members->data_file_name.c_str() );
    return Members->errorNorm < dataFile ("errorNorms/l2Error", -10e10);
}