Esempio n. 1
0
bool
NodeErrorCheckingRule :: check(Domain *domain, TimeStep *tStep)
{
    // Rule doesn't apply yet.
    if ( tStep->giveNumber() != tstep ) {
        return true;
    }

    DofManager *dman = domain->giveGlobalDofManager(number);
    if ( !dman ) {
        if ( domain->giveEngngModel()->isParallel() ) {
            return true;
        } else {
            OOFEM_WARNING("Dof manager %d not found.", number);
            return false;
        }
    }

    if ( dman->giveParallelMode() == DofManager_remote || dman->giveParallelMode() == DofManager_null ) {
        return true;
    }

    Dof *dof = dman->giveDofWithID(dofid);

    double dmanValue = dof->giveUnknown(mode, tStep);
    bool check = checkValue(dmanValue);
    if ( !check ) {
        OOFEM_WARNING("Check failed in: tstep %d, node %d, dof %d, mode %d:\n"
                      "value is %.8e, but should be %.8e ( error is %e but tolerance is %e )",
                      tstep, number, dofid, mode,
                      dmanValue, value, fabs(dmanValue-value), tolerance );
    }
    return check;
}
Esempio n. 2
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void Tr21Stokes :: giveIntegratedVelocity(FloatMatrix &answer, TimeStep *tStep )
{
    /*
    * Integrate velocity over element
    */

    IntegrationRule *iRule = integrationRulesArray [ 0 ];
    FloatMatrix v, v_gamma, ThisAnswer, boundaryV, Nmatrix;
    double detJ;
    FloatArray *lcoords, N;
    int i, j, k=0;
    Dof *d;
    GaussPoint *gp;

    v.resize(12,1);
    v.zero();
    boundaryV.resize(2,1);


    for (i=1; i<=this->giveNumberOfDofManagers(); i++) {
        for (j=1; j<=this->giveDofManager(i)->giveNumberOfDofs(); j++) {
            d = this->giveDofManager(i)->giveDof(j);
            if ((d->giveDofID()==V_u) || (d->giveDofID()==V_v)) {
                k=k+1;
                v.at(k,1)=d->giveUnknown(EID_ConservationEquation, VM_Total, tStep);
            /*} else if (d->giveDofID()==A_x) {
                boundaryV.at(1,1)=d->giveUnknown(EID_ConservationEquation, VM_Total, tStep);
            } else if (d->giveDofID()==A_y) {
                boundaryV.at(2,1)=d->giveUnknown(EID_ConservationEquation, VM_Total, tStep);*/
            }
        }
    }

    answer.resize(2,1);
    answer.zero();

    Nmatrix.resize(2,12);

    for (i=0; i<iRule->getNumberOfIntegrationPoints(); i++) {

        gp = iRule->getIntegrationPoint(i);

        lcoords = gp->giveCoordinates();

        this->interpolation_quad.evalN(N, *lcoords, FEIElementGeometryWrapper(this));
        detJ = this->interpolation_quad.giveTransformationJacobian(*lcoords, FEIElementGeometryWrapper(this));

        N.times(detJ*gp->giveWeight());

        for (j=1; j<=6;j++) {
            Nmatrix.at(1,j*2-1)=N.at(j);
            Nmatrix.at(2,j*2)=N.at(j);
        }

        ThisAnswer.beProductOf(Nmatrix,v);
        answer.add(ThisAnswer);

    }

}
double PrescribedGradientBCPeriodic :: giveUnknown(double val, ValueModeType mode, TimeStep *tStep, ActiveDof *dof)
{
    DofManager *master = this->domain->giveDofManager(this->slavemap[dof->giveDofManager()->giveNumber()]);
    DofIDItem id = dof->giveDofID();
    FloatArray *coords = dof->giveDofManager()->giveCoordinates();
    FloatArray *masterCoords = master->giveCoordinates();
    FloatArray dx, uM;
    dx.beDifferenceOf(* coords, * masterCoords );

    int ind;
    if ( id == D_u || id == V_u || id == P_f || id == T_f ) {
        ind = 1;
    } else if ( id == D_v || id == V_v ) {
        ind = 2;
    } else { /*if ( id == D_w || id == V_w )*/   // 3D only:
        ind = 3;
    }

    FloatMatrix grad(3, 3);
    for ( int i = 0; i < this->strain_id.giveSize(); ++i ) {
        Dof *dof = this->strain->giveDofWithID(strain_id[i]);
        grad(i % 3, i / 3) = dof->giveUnknown(mode, tStep);
    }
    uM.beProductOf(grad, dx); // The "jump" part of the unknown ( u^+ = [[u^M]] + u^- )

    return val + uM.at(ind);
}
void IncrementalLinearStatic :: updateDofUnknownsDictionary(DofManager *inode, TimeStep *tStep)
{
    // update DOF unknowns dictionary, where
    // unknowns are hold instead of keeping them in global unknowns
    // vectors in engng instances
    // this is necessary, because during solution equation numbers for
    // particular DOFs may changed, and it is necessary to keep them
    // in DOF level.

    int ndofs = inode->giveNumberOfDofs();
    Dof *iDof;
    double val;
    for ( int i = 1; i <= ndofs; i++ ) {
        iDof = inode->giveDof(i);
        // skip slave DOFs (only master (primary) DOFs have to be updated).
        if (!iDof->isPrimaryDof()) continue;
        val = iDof->giveUnknown(VM_Total, tStep);
        if ( !iDof->hasBc(tStep) ) {
            val += this->incrementOfDisplacementVector.at( iDof->__giveEquationNumber() );
        }

        iDof->updateUnknownsDictionary(tStep, VM_Total_Old, val);
        iDof->updateUnknownsDictionary(tStep, VM_Total, val);
    }
}
Esempio n. 5
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void
Node2NodeContactL :: computeContactTractionAt(GaussPoint *gp, FloatArray &t, FloatArray &gap, TimeStep *tStep)
{
    // should be replaced with a call to constitutive model
    // gap should be in a local system
    if ( gap.at(1) < 0.0 ) {
        
        Dof *dof = masterNode->giveDofWithID( this->giveDofIdArray().at(1) );
        double lambda = dof->giveUnknown(VM_Total, tStep);
        t = {lambda, 0.0, 0.0};
        //printf("lambda %e \n\n", lambda);
    } else {
        t = {0.0, 0.0, 0.0};
    }
  
} 
Esempio n. 6
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void
MatlabExportModule :: doOutputData(TimeStep *tStep, FILE *FID)
{
    Domain *domain  = emodel->giveDomain(1);
    std :: vector< int >DofIDList;
    std :: vector< int > :: iterator it;
    std :: vector< std :: vector< double > * >valuesList;
    std :: vector< double > *values;

    for ( int i = 1; i <= domain->giveNumberOfDofManagers(); i++ ) {
        for ( int j = 1; j <= domain->giveDofManager(i)->giveNumberOfDofs(); j++ ) {
            Dof *thisDof;
            thisDof = domain->giveDofManager(i)->giveDof(j);
            it = std :: find( DofIDList.begin(), DofIDList.end(), thisDof->giveDofID() );

            if ( it == DofIDList.end() ) {
                DofIDList.push_back( thisDof->giveDofID() );
                values = new( std :: vector< double > );
                valuesList.push_back(values);
            } else {
                int pos = it - DofIDList.begin();
                values = valuesList.at(pos);
            }

            double value = thisDof->giveUnknown(EID_MomentumBalance, VM_Total, tStep);
            values->push_back(value);
        }
    }

    fprintf(FID, "\tdata.DofIDs=[");
    for ( size_t i = 0; i < DofIDList.size(); i++ ) {
        fprintf( FID, "%u, ", DofIDList.at(i) );
    }

    fprintf(FID, "];\n");

    for ( size_t i = 0; i < valuesList.size(); i++ ) {
        fprintf(FID, "\tdata.a{%lu}=[", static_cast<long unsigned int>(i) + 1);
        for ( size_t j = 0; j < valuesList.at(i)->size(); j++ ) {
            fprintf( FID, "%f,", valuesList.at(i)->at(j) );
        }

        fprintf(FID, "];\n");
    }
}
Esempio n. 7
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void
CoupledFieldsElement :: computeVectorOfDofIDs(const IntArray &dofIdArray, ValueModeType valueMode, TimeStep *stepN, FloatArray &answer)
{
    // Routine to extract the solution vector for an element given an dofid array.
    // Size will be numberOfDofs and if a certain dofId does not exist a zero is used as value. 
    
    answer.resize( numberOfDofMans * dofIdArray.giveSize() ); // equal number of nodes for all fields
    answer.zero();
    int k = 1;
    for ( int i = 1; i <= numberOfDofMans; i++ ) {
        DofManager *dMan = this->giveDofManager(i);        
        for (int j = 1; j <= dofIdArray.giveSize(); j++ ) {   
            
            if ( dMan->hasDofID( (DofIDItem) dofIdArray.at(j) ) ) {
                Dof *d = dMan->giveDofWithID( dofIdArray.at(j) );
                answer.at(k) = d->giveUnknown(valueMode, stepN);
            }
            k++;
        }
    }
}
void LinearConstraintBC :: assembleVector(FloatArray &answer, TimeStep *tStep, EquationID eid,
                                          CharType type, ValueModeType mode,
                                          const UnknownNumberingScheme &s, FloatArray *eNorms)
{
  IntArray loc, lambdaeq(1);
  FloatArray vec(1);
  double factor=1.;

  if (!this->rhsType.contains((int) type)) return ;
  if (!this->isImposed(tStep)) return;

  if (type == InternalForcesVector) {
    // compute true residual
    int size = this->weights.giveSize();
    Dof *idof;

    // assemble location array
    for ( int _i = 1; _i <= size; _i++ ) {
        factor=1.;
        if(weightsLtf.giveSize()){
            factor = domain->giveLoadTimeFunction(weightsLtf.at(_i))->__at(tStep->giveIntrinsicTime());
        }
        idof = this->domain->giveDofManager( this->dofmans.at(_i) )->giveDof( this->dofs.at(_i) );
        answer.at(s.giveDofEquationNumber(idof)) += md->giveDof(1)->giveUnknown(mode, tStep) * this->weights.at(_i)*factor;
        answer.at(s.giveDofEquationNumber( md->giveDof(1) )) += idof->giveUnknown(mode, tStep) * this->weights.at(_i)*factor;
    }

  } else {
    // use rhs value

    if(rhsLtf){
      factor = domain->giveLoadTimeFunction(rhsLtf)->__at(tStep->giveIntrinsicTime());
    }
    this->giveLocArray(s, loc, lambdaeq.at(1));
    vec.at(1) = rhs*factor;
    answer.assemble(vec, lambdaeq);
  }
}
void
NonStationaryTransportProblem :: applyIC(TimeStep *stepWhenIcApply)
{
    Domain *domain = this->giveDomain(1);
    int neq =  this->giveNumberOfEquations(EID_ConservationEquation);
    FloatArray *solutionVector;
    double val;

#ifdef VERBOSE
    OOFEM_LOG_INFO("Applying initial conditions\n");
#endif
    int nDofs, j, k, jj;
    int nman  = domain->giveNumberOfDofManagers();
    DofManager *node;
    Dof *iDof;

    UnknownsField->advanceSolution(stepWhenIcApply);
    solutionVector = UnknownsField->giveSolutionVector(stepWhenIcApply);
    solutionVector->resize(neq);
    solutionVector->zero();

    for ( j = 1; j <= nman; j++ ) {
        node = domain->giveDofManager(j);
        nDofs = node->giveNumberOfDofs();

        for ( k = 1; k <= nDofs; k++ ) {
            // ask for initial values obtained from
            // bc (boundary conditions) and ic (initial conditions)
            iDof  =  node->giveDof(k);
            if ( !iDof->isPrimaryDof() ) {
                continue;
            }

            jj = iDof->__giveEquationNumber();
            if ( jj ) {
                val = iDof->giveUnknown(EID_ConservationEquation, VM_Total, stepWhenIcApply);
                solutionVector->at(jj) = val;
                //update in dictionary, if the problem is growing/decreasing
                if ( this->changingProblemSize ) {
                    iDof->updateUnknownsDictionary(stepWhenIcApply, EID_MomentumBalance, VM_Total, val);
                }
            }
        }
    }

    int nelem = domain->giveNumberOfElements();
    
    //project initial temperature to integration points

//     for ( j = 1; j <= nelem; j++ ) {
//         domain->giveElement(j)->updateInternalState(stepWhenIcApply);
//     }

#ifdef __CEMHYD_MODULE
    // Not relevant in linear case, but needed for CemhydMat for temperature averaging before solving balance equations
    // Update element state according to given ic
    TransportElement *element;
    CemhydMat *cem;
    for ( j = 1; j <= nelem; j++ ) {
        element = ( TransportElement * ) domain->giveElement(j);
        //assign status to each integration point on each element
        if ( element->giveMaterial()->giveClassID() == CemhydMatClass ) {
            element->giveMaterial()->initMaterial(element); //create microstructures and statuses on specific GPs
            element->updateInternalState(stepWhenIcApply);   //store temporary unequilibrated temperature
            element->updateYourself(stepWhenIcApply);   //store equilibrated temperature
            cem = ( CemhydMat * ) element->giveMaterial();
            cem->clearWeightTemperatureProductVolume(element);
            cem->storeWeightTemperatureProductVolume(element, stepWhenIcApply);
        }
    }

    //perform averaging on each material instance of CemhydMatClass
    int nmat = domain->giveNumberOfMaterialModels();
    for ( j = 1; j <= nmat; j++ ) {
        if ( domain->giveMaterial(j)->giveClassID() == CemhydMatClass ) {
            cem = ( CemhydMat * ) domain->giveMaterial(j);
            cem->averageTemperature();
        }
    }
#endif //__CEMHYD_MODULE
}
Esempio n. 10
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void DEIDynamic :: solveYourselfAt(TimeStep *tStep)
{
    //
    // creates system of governing eq's and solves them at given time step
    //
    // this is an explicit problem: we assemble governing equating at time t
    // and solution is obtained for time t+dt
    //
    // first assemble problem at current time step to obtain results in following
    // time step.
    // and then print results for this step also.
    // for first time step we need special start code
    Domain *domain = this->giveDomain(1);
    int nelem = domain->giveNumberOfElements();
    int nman = domain->giveNumberOfDofManagers();
    IntArray loc;
    Element *element;
    DofManager *node;
    Dof *iDof;
    int nDofs, neq;
    int i, k, n, j, jj, kk, init = 0;
    double coeff, maxDt, maxOmi, maxOm = 0., maxOmEl, c1, c2, c3;
    FloatMatrix charMtrx, charMtrx2;
    FloatArray previousDisplacementVector;


    neq = this->giveNumberOfEquations(EID_MomentumBalance);
    if ( tStep->giveNumber() == giveNumberOfFirstStep() ) {
        init = 1;
#ifdef VERBOSE
        OOFEM_LOG_INFO("Assembling mass matrix\n");
#endif

        //
        // first step  assemble mass Matrix
        //

        massMatrix.resize(neq);
        massMatrix.zero();
        EModelDefaultEquationNumbering dn;
        for ( i = 1; i <= nelem; i++ ) {
            element = domain->giveElement(i);
            element->giveLocationArray(loc, EID_MomentumBalance, dn);
            element->giveCharacteristicMatrix(charMtrx,  LumpedMassMatrix, tStep);
            // charMtrx.beLumpedOf(fullCharMtrx);
            element->giveCharacteristicMatrix(charMtrx2, StiffnessMatrix, tStep);

            //
            // assemble it manually
            //
#ifdef DEBUG
            if ( ( n = loc.giveSize() ) != charMtrx.giveNumberOfRows() ) {
                _error("solveYourselfAt : dimension mismatch");
            }

#endif

            n = loc.giveSize();

            maxOmEl = 0.;
            for ( j = 1; j <= n; j++ ) {
                if ( charMtrx.at(j, j) > ZERO_MASS ) {
                    maxOmi =  charMtrx2.at(j, j) / charMtrx.at(j, j);
                    if ( init ) {
                        maxOmEl = ( maxOmEl > maxOmi ) ? ( maxOmEl ) : ( maxOmi );
                    }
                }
            }

            maxOm = ( maxOm > maxOmEl ) ? ( maxOm ) : ( maxOmEl );

            for ( j = 1; j <= n; j++ ) {
                jj = loc.at(j);
                if ( ( jj ) && ( charMtrx.at(j, j) <= ZERO_MASS ) ) {
                    charMtrx.at(j, j) = charMtrx2.at(j, j) / maxOmEl;
                }
            }

            for ( j = 1; j <= n; j++ ) {
                jj = loc.at(j);
                if ( jj ) {
                    massMatrix.at(jj) += charMtrx.at(j, j);
                }
            }
        }

        // if init - try to determine the best deltaT
        if ( init ) {
            maxDt = 2 / sqrt(maxOm);
            if ( deltaT > maxDt ) {
                OOFEM_LOG_RELEVANT("DEIDynamic: deltaT reduced to %e\n", maxDt);
                deltaT = maxDt;
                tStep->setTimeIncrement(deltaT);
            }
        }


        //
        // special init step - compute displacements at tstep 0
        //
        displacementVector.resize(neq);
        displacementVector.zero();
        nextDisplacementVector.resize(neq);
        nextDisplacementVector.zero();
        velocityVector.resize(neq);
        velocityVector.zero();
        accelerationVector.resize(neq);
        accelerationVector.zero();


        for ( j = 1; j <= nman; j++ ) {
            node = domain->giveDofManager(j);
            nDofs = node->giveNumberOfDofs();

            for ( k = 1; k <= nDofs; k++ ) {
                // ask for initial values obtained from
                // bc (boundary conditions) and ic (initial conditions)
                // now we are setting initial cond. for step -1.
                iDof  =  node->giveDof(k);
                if ( !iDof->isPrimaryDof() ) {
                    continue;
                }

                jj = iDof->__giveEquationNumber();
                if ( jj ) {
                    nextDisplacementVector.at(jj) = iDof->giveUnknown(EID_MomentumBalance, VM_Total, tStep);
                    // become displacementVector after init
                    velocityVector.at(jj)     = iDof->giveUnknown(EID_MomentumBalance, VM_Velocity, tStep);
                    // accelerationVector = iDof->giveUnknown(AccelerartionVector,tStep) ;
                }
            }
        }

        for ( j = 1; j <= neq; j++ ) {
            nextDisplacementVector.at(j) -= velocityVector.at(j) * ( deltaT );
        }

        return;
    } // end of init step

#ifdef VERBOSE
    OOFEM_LOG_INFO("Assembling right hand side\n");
#endif


    c1 = ( 1. / ( deltaT * deltaT ) );
    c2 = ( 1. / ( 2. * deltaT ) );
    c3 = ( 2. / ( deltaT * deltaT ) );

    previousDisplacementVector = displacementVector;
    displacementVector         = nextDisplacementVector;

    //
    // assembling the element part of load vector
    //
    loadVector.resize( this->giveNumberOfEquations(EID_MomentumBalance) );
    loadVector.zero();
    this->assembleVector(loadVector, tStep, EID_MomentumBalance, ExternalForcesVector,
                         VM_Total, EModelDefaultEquationNumbering(), domain);

    //
    // assembling additional parts of right hand side
    //
    EModelDefaultEquationNumbering dn;
    for ( i = 1; i <= nelem; i++ ) {
        element = domain->giveElement(i);
        element->giveLocationArray(loc, EID_MomentumBalance, dn);
        element->giveCharacteristicMatrix(charMtrx, StiffnessMatrix, tStep);
        n = loc.giveSize();
        for ( j = 1; j <= n; j++ ) {
            jj = loc.at(j);
            if ( jj ) {
                for ( k = 1; k <= n; k++ ) {
                    kk = loc.at(k);
                    if ( kk ) {
                        loadVector.at(jj) -= charMtrx.at(j, k) * displacementVector.at(kk);
                    }
                }

                //
                // if init step - find minimum period of vibration in order to
                // determine maximal admissible time step
                //
                //maxOmi =  charMtrx.at(j,j)/massMatrix.at(jj) ;
                //if (init) maxOm = (maxOm > maxOmi) ? (maxOm) : (maxOmi) ;
            }
        }
    }



    for ( j = 1; j <= neq; j++ ) {
        coeff =  massMatrix.at(j);
        loadVector.at(j) += coeff * c3 * displacementVector.at(j) -
                            coeff * ( c1 - dumpingCoef * c2 ) *
                            previousDisplacementVector.at(j);
    }

    //
    // set-up numerical model
    //
    /* it is not necessary to call numerical method
     * approach used here is not good, but effective enough
     * inverse of diagonal mass matrix is done here
     */
    //
    // call numerical model to solve arose problem - done locally here
    //
#ifdef VERBOSE
    OOFEM_LOG_RELEVANT( "Solving [step number %8d, time %15e]\n", tStep->giveNumber(), tStep->giveTargetTime() );
#endif
    double prevD;

    for ( i = 1; i <= neq; i++ ) {
        prevD = previousDisplacementVector.at(i);
        nextDisplacementVector.at(i) = loadVector.at(i) /
                                       ( massMatrix.at(i) * ( c1 + dumpingCoef * c2 ) );
        velocityVector.at(i) = nextDisplacementVector.at(i) - prevD;
        accelerationVector.at(i) =
            nextDisplacementVector.at(i) -
            2. * displacementVector.at(i) + prevD;
    }

    accelerationVector.times(c1);
    velocityVector.times(c2);
}
Esempio n. 11
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void
NonLinearDynamic :: proceedStep(int di, TimeStep *tStep)
{
    // creates system of governing eq's and solves them at given time step
    // first assemble problem at current time step

    int neq = this->giveNumberOfDomainEquations(1, EModelDefaultEquationNumbering());

    // Time-stepping constants
    this->determineConstants(tStep);

    if ( ( tStep->giveNumber() == giveNumberOfFirstStep() ) && initFlag ) {
        // Initialization
        incrementOfDisplacement.resize(neq);
        incrementOfDisplacement.zero();
        totalDisplacement.resize(neq);
        totalDisplacement.zero();
        velocityVector.resize(neq);
        velocityVector.zero();
        accelerationVector.resize(neq);
        accelerationVector.zero();
        internalForces.resize(neq);
        internalForces.zero();
        previousIncrementOfDisplacement.resize(neq);
        previousIncrementOfDisplacement.zero();
        previousTotalDisplacement.resize(neq);
        previousTotalDisplacement.zero();
        previousVelocityVector.resize(neq);
        previousVelocityVector.zero();
        previousAccelerationVector.resize(neq);
        previousAccelerationVector.zero();
        previousInternalForces.resize(neq);
        previousInternalForces.zero();

        TimeStep *stepWhenIcApply = new TimeStep(giveNumberOfTimeStepWhenIcApply(), this, 0,
                                                 -deltaT, deltaT, 0);

        int nDofs, j, k, jj;
        int nman = this->giveDomain(di)->giveNumberOfDofManagers();
        DofManager *node;
        Dof *iDof;

        // Considering initial conditions.
        for ( j = 1; j <= nman; j++ ) {
            node = this->giveDomain(di)->giveDofManager(j);
            nDofs = node->giveNumberOfDofs();

            for ( k = 1; k <= nDofs; k++ ) {
                // Ask for initial values obtained from
                // bc (boundary conditions) and ic (initial conditions).
                iDof  =  node->giveDof(k);
                if ( !iDof->isPrimaryDof() ) {
                    continue;
                }

                jj = iDof->__giveEquationNumber();
                if ( jj ) {
                    totalDisplacement.at(jj)  = iDof->giveUnknown(VM_Total, stepWhenIcApply);
                    velocityVector.at(jj)     = iDof->giveUnknown(VM_Velocity, stepWhenIcApply);
                    accelerationVector.at(jj) = iDof->giveUnknown(VM_Acceleration, stepWhenIcApply);
                }
            }
        }

        this->giveInternalForces(internalForces, true, di, tStep);
    }

    if ( initFlag ) {
        // First assemble problem at current time step.
        // Option to take into account initial conditions.
        if ( !effectiveStiffnessMatrix ) {
            effectiveStiffnessMatrix = classFactory.createSparseMtrx(sparseMtrxType);
            massMatrix = classFactory.createSparseMtrx(sparseMtrxType);
        }

        if ( effectiveStiffnessMatrix == NULL || massMatrix == NULL ) {
            _error("proceedStep: sparse matrix creation failed");
        }

        if ( nonlocalStiffnessFlag ) {
            if ( !effectiveStiffnessMatrix->isAsymmetric() ) {
                _error("proceedStep: effectiveStiffnessMatrix does not support asymmetric storage");
            }
        }

        effectiveStiffnessMatrix->buildInternalStructure( this, di, EID_MomentumBalance, EModelDefaultEquationNumbering() );
        massMatrix->buildInternalStructure( this, di, EID_MomentumBalance, EModelDefaultEquationNumbering() );

        // Assemble mass matrix
        this->assemble(massMatrix, tStep, EID_MomentumBalance, MassMatrix,
                       EModelDefaultEquationNumbering(), this->giveDomain(di));

        // Initialize vectors
        help.resize(neq);
        help.zero();
        rhs.resize(neq);
        rhs.zero();
        rhs2.resize(neq);
        rhs2.zero();

        previousIncrementOfDisplacement.resize(neq);
        previousTotalDisplacement.resize(neq);
        previousVelocityVector.resize(neq);
        previousAccelerationVector.resize(neq);
        previousInternalForces.resize(neq);
        for ( int i = 1; i <= neq; i++ ) {
            previousIncrementOfDisplacement.at(i) = incrementOfDisplacement.at(i);
            previousTotalDisplacement.at(i)       = totalDisplacement.at(i);
            previousVelocityVector.at(i)          = velocityVector.at(i);
            previousAccelerationVector.at(i)      = accelerationVector.at(i);
            previousInternalForces.at(i)          = internalForces.at(i);
        }

        forcesVector.resize(neq);
        forcesVector.zero();

        totIterations = 0;
        initFlag = 0;
    }

#ifdef VERBOSE
    OOFEM_LOG_DEBUG("Assembling load\n");
#endif

    // Assemble the incremental reference load vector.
    this->assembleIncrementalReferenceLoadVectors(incrementalLoadVector, incrementalLoadVectorOfPrescribed,
                                                  refLoadInputMode, this->giveDomain(di), EID_MomentumBalance, tStep);

    // Assembling the effective load vector
    for ( int i = 1; i <= neq; i++ ) {
        help.at(i) = a2 * previousVelocityVector.at(i) + a3 * previousAccelerationVector.at(i)
            + eta * ( a4 * previousVelocityVector.at(i)
                      + a5 * previousAccelerationVector.at(i)
                      + a6 * previousIncrementOfDisplacement.at(i) );
    }

    massMatrix->times(help, rhs);

    if ( delta != 0 ) {
        for ( int i = 1; i <= neq; i++ ) {
            help.at(i) = delta * ( a4 * previousVelocityVector.at(i)
                                   + a5 * previousAccelerationVector.at(i)
                                   + a6 * previousIncrementOfDisplacement.at(i) );
        }
        this->timesMtrx(help, rhs2, TangentStiffnessMatrix, this->giveDomain(di), tStep);

        help.zero();
        for ( int i = 1; i <= neq; i++ ) {
            rhs.at(i) += rhs2.at(i);
        }
    }

    for ( int i = 1; i <= neq; i++ ) {
        rhs.at(i) += incrementalLoadVector.at(i) - previousInternalForces.at(i);
    }

    //
    // Set-up numerical model.
    //
    this->giveNumericalMethod( this->giveCurrentMetaStep() );

    //
    // Call numerical model to solve problem.
    //
    double loadLevel = 1.0;

    if ( totIterations == 0 ) { incrementOfDisplacement.zero(); }

    if ( initialLoadVector.isNotEmpty() ) {
        numMetStatus = nMethod->solve(effectiveStiffnessMatrix, & rhs, & initialLoadVector,
                                      & totalDisplacement, & incrementOfDisplacement, & forcesVector,
                                      internalForcesEBENorm, loadLevel, refLoadInputMode, currentIterations, tStep);
    } else {
        numMetStatus = nMethod->solve(effectiveStiffnessMatrix, & rhs, NULL,
                                      & totalDisplacement, & incrementOfDisplacement, & forcesVector,
                                      internalForcesEBENorm, loadLevel, refLoadInputMode, currentIterations, tStep);
    }

    for ( int i = 1; i <= neq; i++ ) {
        rhs.at(i)                = previousVelocityVector.at(i);
        rhs2.at(i)               = previousAccelerationVector.at(i);
        accelerationVector.at(i) = a0 * incrementOfDisplacement.at(i) - a2 * rhs.at(i) - a3 * rhs2.at(i);
        velocityVector.at(i)     = a1 * incrementOfDisplacement.at(i) - a4 * rhs.at(i) - a5 * rhs2.at(i)
            - a6 * previousIncrementOfDisplacement.at(i);
    }
    totIterations += currentIterations;
}
void GnuplotExportModule::outputBoundaryCondition(PrescribedGradientBCWeak &iBC, TimeStep *tStep)
{
    FloatArray stress;
    iBC.computeField(stress, tStep);

    printf("Mean stress computed in Gnuplot export module: "); stress.printYourself();

    double time = 0.0;

    TimeStep *ts = emodel->giveCurrentStep();
    if ( ts != NULL ) {
        time = ts->giveTargetTime();
    }

    int bcIndex = iBC.giveNumber();

    std :: stringstream strMeanStress;
    strMeanStress << "PrescribedGradientGnuplotMeanStress" << bcIndex << "Time" << time << ".dat";
    std :: string nameMeanStress = strMeanStress.str();
    std::vector<double> componentArray, stressArray;

    for(int i = 1; i <= stress.giveSize(); i++) {
        componentArray.push_back(i);
        stressArray.push_back(stress.at(i));
    }

    XFEMDebugTools::WriteArrayToGnuplot(nameMeanStress, componentArray, stressArray);


    // Homogenized strain
    FloatArray grad;
    iBC.giveGradientVoigt(grad);
    outputGradient(iBC.giveNumber(), *iBC.giveDomain(), grad, tStep);

#if 0
    FloatArray grad;
    iBC.giveGradientVoigt(grad);
    double timeFactor = iBC.giveTimeFunction()->evaluate(ts, VM_Total);
    printf("timeFactor: %e\n", timeFactor );
    grad.times(timeFactor);
    printf("Mean grad computed in Gnuplot export module: "); grad.printYourself();

    std :: stringstream strMeanGrad;
    strMeanGrad << "PrescribedGradientGnuplotMeanGrad" << bcIndex << "Time" << time << ".dat";
    std :: string nameMeanGrad = strMeanGrad.str();
    std::vector<double> componentArrayGrad, gradArray;

    for(int i = 1; i <= grad.giveSize(); i++) {
        componentArrayGrad.push_back(i);
        gradArray.push_back(grad.at(i));
    }

    XFEMDebugTools::WriteArrayToGnuplot(nameMeanGrad, componentArrayGrad, gradArray);
#endif

    if(mExportBoundaryConditionsExtra) {

        // Traction node coordinates
        std::vector< std::vector<FloatArray> > nodePointArray;
        size_t numTracEl = iBC.giveNumberOfTractionElements();
        for(size_t i = 0; i < numTracEl; i++) {

            std::vector<FloatArray> points;
            FloatArray xS, xE;
            iBC.giveTractionElCoord(i, xS, xE);
            points.push_back(xS);
            points.push_back(xE);

            nodePointArray.push_back(points);
        }

        std :: stringstream strTractionNodes;
        strTractionNodes << "TractionNodesGnuplotTime" << time << ".dat";
        std :: string nameTractionNodes = strTractionNodes.str();

        WritePointsToGnuplot(nameTractionNodes, nodePointArray);



        // Traction element normal direction
        std::vector< std::vector<FloatArray> > nodeNormalArray;
        for(size_t i = 0; i < numTracEl; i++) {

            std::vector<FloatArray> points;
            FloatArray n,t;
            iBC.giveTractionElNormal(i, n,t);
            points.push_back(n);
            points.push_back(n);

            nodeNormalArray.push_back(points);
        }

        std :: stringstream strTractionNodeNormals;
        strTractionNodeNormals << "TractionNodeNormalsGnuplotTime" << time << ".dat";
        std :: string nameTractionNodeNormals = strTractionNodeNormals.str();

        WritePointsToGnuplot(nameTractionNodeNormals, nodeNormalArray);



        // Traction (x,y)
        std::vector< std::vector<FloatArray> > nodeTractionArray;
        for(size_t i = 0; i < numTracEl; i++) {

            std::vector<FloatArray> tractions;
            FloatArray tS, tE;

            iBC.giveTraction(i, tS, tE, VM_Total, tStep);

            tractions.push_back(tS);
            tractions.push_back(tE);
            nodeTractionArray.push_back(tractions);
        }

        std :: stringstream strTractions;
        strTractions << "TractionsGnuplotTime" << time << ".dat";
        std :: string nameTractions = strTractions.str();

        WritePointsToGnuplot(nameTractions, nodeTractionArray);



        // Arc position along the boundary
        std::vector< std::vector<FloatArray> > arcPosArray;
        for(size_t i = 0; i < numTracEl; i++) {
            std::vector<FloatArray> arcPos;
            double xiS = 0.0, xiE = 0.0;
            iBC.giveTractionElArcPos(i, xiS, xiE);
            arcPos.push_back( FloatArray{xiS} );
            arcPos.push_back( FloatArray{xiE} );

            arcPosArray.push_back(arcPos);
        }

        std :: stringstream strArcPos;
        strArcPos << "ArcPosGnuplotTime" << time << ".dat";
        std :: string nameArcPos = strArcPos.str();

        WritePointsToGnuplot(nameArcPos, arcPosArray);


        // Traction (normal, tangent)
        std::vector< std::vector<FloatArray> > nodeTractionNTArray;
        for(size_t i = 0; i < numTracEl; i++) {

            std::vector<FloatArray> tractions;
            FloatArray tS, tE;

            iBC.giveTraction(i, tS, tE, VM_Total, tStep);
            FloatArray n,t;
            iBC.giveTractionElNormal(i, n, t);


            double tSn = tS.dotProduct(n,2);
            double tSt = tS.dotProduct(t,2);
            tractions.push_back( {tSn ,tSt} );

            double tEn = tE.dotProduct(n,2);
            double tEt = tE.dotProduct(t,2);
            tractions.push_back( {tEn, tEt} );
            nodeTractionNTArray.push_back(tractions);
        }

        std :: stringstream strTractionsNT;
        strTractionsNT << "TractionsNormalTangentGnuplotTime" << time << ".dat";
        std :: string nameTractionsNT = strTractionsNT.str();

        WritePointsToGnuplot(nameTractionsNT, nodeTractionNTArray);



        // Boundary points and displacements
        IntArray boundaries, bNodes;
        iBC.giveBoundaries(boundaries);

        std::vector< std::vector<FloatArray> > bndNodes;

        for ( int pos = 1; pos <= boundaries.giveSize() / 2; ++pos ) {

            Element *e = iBC.giveDomain()->giveElement( boundaries.at(pos * 2 - 1) );
            int boundary = boundaries.at(pos * 2);

            e->giveInterpolation()->boundaryGiveNodes(bNodes, boundary);

            std::vector<FloatArray> bndSegNodes;

            // Add the start and end nodes of the segment
            DofManager *startNode   = e->giveDofManager( bNodes[0] );
            FloatArray xS    = *(startNode->giveCoordinates());

            Dof *dSu = startNode->giveDofWithID(D_u);
            double dU = dSu->giveUnknown(VM_Total, tStep);
            xS.push_back(dU);

            Dof *dSv = startNode->giveDofWithID(D_v);
            double dV = dSv->giveUnknown(VM_Total, tStep);
            xS.push_back(dV);

            bndSegNodes.push_back(xS);

            DofManager *endNode     = e->giveDofManager( bNodes[1] );
            FloatArray xE    = *(endNode->giveCoordinates());

            Dof *dEu = endNode->giveDofWithID(D_u);
            dU = dEu->giveUnknown(VM_Total, tStep);
            xE.push_back(dU);

            Dof *dEv = endNode->giveDofWithID(D_v);
            dV = dEv->giveUnknown(VM_Total, tStep);
            xE.push_back(dV);

            bndSegNodes.push_back(xE);

            bndNodes.push_back(bndSegNodes);
        }

        std :: stringstream strBndNodes;
        strBndNodes << "BndNodesGnuplotTime" << time << ".dat";
        std :: string nameBndNodes = strBndNodes.str();

        WritePointsToGnuplot(nameBndNodes, bndNodes);

    }
}
Esempio n. 13
0
void NlDEIDynamic :: solveYourselfAt(TimeStep *tStep)
{
    //
    // Creates system of governing eq's and solves them at given time step.
    //

    Domain *domain = this->giveDomain(1);
    int neq = this->giveNumberOfEquations(EID_MomentumBalance);
    int nman  = domain->giveNumberOfDofManagers();

    DofManager *node;
    Dof *iDof;

    int nDofs;
    int i, k, j, jj;
    double coeff, maxDt, maxOm = 0.;
    double prevIncrOfDisplacement, incrOfDisplacement;

    if ( initFlag ) {
#ifdef VERBOSE
        OOFEM_LOG_DEBUG("Assembling mass matrix\n");
#endif

        //
        // Assemble mass matrix.
        //
        this->computeMassMtrx(massMatrix, maxOm, tStep);

        if ( drFlag ) {
            // If dynamic relaxation: Assemble amplitude load vector.
            loadRefVector.resize(neq);
            loadRefVector.zero();

            this->computeLoadVector(loadRefVector, VM_Total, tStep);

#ifdef __PARALLEL_MODE
            // Compute the processor part of load vector norm pMp
            this->pMp = 0.0;
            double my_pMp = 0.0, coeff = 1.0;
            int eqNum, ndofs, ndofman = domain->giveNumberOfDofManagers();
            dofManagerParallelMode dofmanmode;
            DofManager *dman;
            Dof *jdof;
            for ( int dm = 1; dm <= ndofman; dm++ ) {
                dman = domain->giveDofManager(dm);
                ndofs = dman->giveNumberOfDofs();
                dofmanmode = dman->giveParallelMode();

                // Skip all remote and null dofmanagers
                coeff = 1.0;
                if ( ( dofmanmode == DofManager_remote ) || ( ( dofmanmode == DofManager_null ) ) ) {
                    continue;
                } else if ( dofmanmode == DofManager_shared ) {
                    coeff = 1. / dman->givePartitionsConnectivitySize();
                }

                // For shared nodes we add locally an average = 1/givePartitionsConnectivitySize()*contribution,
                for ( j = 1; j <= ndofs; j++ ) {
                    jdof = dman->giveDof(j);
                    if ( jdof->isPrimaryDof() && ( eqNum = jdof->__giveEquationNumber() ) ) {
                        my_pMp += coeff * loadRefVector.at(eqNum) * loadRefVector.at(eqNum) / massMatrix.at(eqNum);
                    }
                }
            }

            // Sum up the contributions from processors.
            MPI_Allreduce(& my_pMp, & pMp, 1, MPI_DOUBLE, MPI_SUM, MPI_COMM_WORLD);
#else
            this->pMp = 0.0;
            for ( i = 1; i <= neq; i++ ) {
                pMp += loadRefVector.at(i) * loadRefVector.at(i) / massMatrix.at(i);
            }
#endif
            // Solve for rate of loading process (parameter "c") (undamped system assumed),
            if ( dumpingCoef < 1.e-3 ) {
                c = 3.0 * this->pyEstimate / pMp / Tau / Tau;
            } else {
                c = this->pyEstimate * Tau * dumpingCoef * dumpingCoef * dumpingCoef / pMp /
                    ( -3.0 / 2.0 + dumpingCoef * Tau + 2.0 * exp(-dumpingCoef * Tau) - 0.5 * exp(-2.0 * dumpingCoef * Tau) );
            }
        }

        initFlag = 0;
    }


    if ( tStep->giveNumber() == giveNumberOfFirstStep() ) {
        //
        // Special init step - Compute displacements at tstep 0.
        //
        displacementVector.resize(neq);
        displacementVector.zero();
        previousIncrementOfDisplacementVector.resize(neq);
        previousIncrementOfDisplacementVector.zero();
        velocityVector.resize(neq);
        velocityVector.zero();
        accelerationVector.resize(neq);
        accelerationVector.zero();

        for ( j = 1; j <= nman; j++ ) {
            node = domain->giveDofManager(j);
            nDofs = node->giveNumberOfDofs();

            for ( k = 1; k <= nDofs; k++ ) {
                // Ask for initial values obtained from
                // bc (boundary conditions) and ic (initial conditions)
                // all dofs are expected to be  DisplacementVector type.
                iDof  =  node->giveDof(k);
                if ( !iDof->isPrimaryDof() ) {
                    continue;
                }

                jj = iDof->__giveEquationNumber();
                if ( jj ) {
                    displacementVector.at(jj) = iDof->giveUnknown(EID_MomentumBalance, VM_Total, tStep);
                    velocityVector.at(jj)     = iDof->giveUnknown(EID_MomentumBalance, VM_Velocity, tStep);
                    accelerationVector.at(jj)    = iDof->giveUnknown(EID_MomentumBalance, VM_Acceleration, tStep) ;
                }
            }
        }

        //
        // Set-up numerical model.
        //

        // Try to determine the best deltaT,
        maxDt = 2.0 / sqrt(maxOm);
        if ( deltaT > maxDt ) {
            // Print reduced time step increment and minimum period Tmin
            OOFEM_LOG_RELEVANT("deltaT reduced to %e, Tmin is %e\n", maxDt, maxDt * M_PI);
            deltaT = maxDt;
            tStep->setTimeIncrement(deltaT);
        }

        for ( j = 1; j <= neq; j++ ) {
            previousIncrementOfDisplacementVector.at(j) =  velocityVector.at(j) * ( deltaT );
            displacementVector.at(j) -= previousIncrementOfDisplacementVector.at(j);
        }
#ifdef VERBOSE
        OOFEM_LOG_RELEVANT( "\n\nSolving [Step number %8d, Time %15e]\n", tStep->giveNumber(), tStep->giveTargetTime() );
#endif
        return;
    } // end of init step

#ifdef VERBOSE
    OOFEM_LOG_DEBUG("Assembling right hand side\n");
#endif

    for ( i = 1; i <= neq; i++ ) {
        displacementVector.at(i) += previousIncrementOfDisplacementVector.at(i);
    }

    // Update solution state counter
    tStep->incrementStateCounter();

    // Compute internal forces.
    this->giveInternalForces( internalForces, false, 1, tStep );

    if ( !drFlag ) {
        //
        // Assembling the element part of load vector.
        //
        this->computeLoadVector(loadVector, VM_Total, tStep);
        //
        // Assembling additional parts of right hand side.
        //
        for ( k = 1; k <= neq; k++ ) {
            loadVector.at(k) -= internalForces.at(k);
        }
    } else {
        // Dynamic relaxation
        // compute load factor
        pt = 0.0;

#ifdef __PARALLEL_MODE
        double my_pt = 0.0, coeff = 1.0;
        int eqNum, ndofs, ndofman = domain->giveNumberOfDofManagers();
        dofManagerParallelMode dofmanmode;
        DofManager *dman;
        Dof *jdof;
        for ( int dm = 1; dm <= ndofman; dm++ ) {
            dman = domain->giveDofManager(dm);
            ndofs = dman->giveNumberOfDofs();
            dofmanmode = dman->giveParallelMode();
            // skip all remote and null dofmanagers
            coeff = 1.0;
            if ( ( dofmanmode == DofManager_remote ) || ( dofmanmode == DofManager_null ) ) {
                continue;
            } else if ( dofmanmode == DofManager_shared ) {
                coeff = 1. / dman->givePartitionsConnectivitySize();
            }

            // For shared nodes we add locally an average= 1/givePartitionsConnectivitySize()*contribution.
            for ( j = 1; j <= ndofs; j++ ) {
                jdof = dman->giveDof(j);
                if ( jdof->isPrimaryDof() && ( eqNum = jdof->__giveEquationNumber() ) ) {
                    my_pt += coeff * internalForces.at(eqNum) * loadRefVector.at(eqNum) / massMatrix.at(eqNum);
                }
            }
        }

        // Sum up the contributions from processors.
        MPI_Allreduce(& my_pt, & pt, 1, MPI_DOUBLE, MPI_SUM, MPI_COMM_WORLD);
#else
        for ( k = 1; k <= neq; k++ ) {
            pt += internalForces.at(k) * loadRefVector.at(k) / massMatrix.at(k);
        }

#endif
        pt = pt / pMp;
        if ( dumpingCoef < 1.e-3 ) {
            pt += c * ( Tau - tStep->giveTargetTime() ) / Tau;
        } else {
            pt += c * ( 1.0 - exp( dumpingCoef * ( tStep->giveTargetTime() - Tau ) ) ) / dumpingCoef / Tau;
        }

        loadVector.resize( this->giveNumberOfEquations(EID_MomentumBalance) );
        for ( k = 1; k <= neq; k++ ) {
            loadVector.at(k) = pt * loadRefVector.at(k) - internalForces.at(k);
        }


        // Compute relative error.
        double err = 0.0;
#ifdef __PARALLEL_MODE
        double my_err = 0.0;

        for ( int dm = 1; dm <= ndofman; dm++ ) {
            dman = domain->giveDofManager(dm);
            ndofs = dman->giveNumberOfDofs();
            dofmanmode = dman->giveParallelMode();
            // Skip all remote and null dofmanagers.
            coeff = 1.0;
            if ( ( dofmanmode == DofManager_remote ) || ( dofmanmode == DofManager_null ) ) {
                continue;
            } else if ( dofmanmode == DofManager_shared ) {
                coeff = 1. / dman->givePartitionsConnectivitySize();
            }

            // For shared nodes we add locally an average= 1/givePartitionsConnectivitySize()*contribution.
            for ( j = 1; j <= ndofs; j++ ) {
                jdof = dman->giveDof(j);
                if ( jdof->isPrimaryDof() && ( eqNum = jdof->__giveEquationNumber() ) ) {
                    my_err += coeff * loadVector.at(eqNum) * loadVector.at(eqNum) / massMatrix.at(eqNum);
                }
            }
        }

        // Sum up the contributions from processors.
        MPI_Allreduce(& my_err, & err, 1, MPI_DOUBLE, MPI_SUM, MPI_COMM_WORLD);

#else
        for ( k = 1; k <= neq; k++ ) {
            err = loadVector.at(k) * loadVector.at(k) / massMatrix.at(k);
        }

#endif
        err = err / ( pMp * pt * pt );
        OOFEM_LOG_RELEVANT("Relative error is %e, loadlevel is %e\n", err, pt);
    }

    for ( j = 1; j <= neq; j++ ) {
        coeff =  massMatrix.at(j);
        loadVector.at(j) +=
            coeff * ( ( 1. / ( deltaT * deltaT ) ) - dumpingCoef * 1. / ( 2. * deltaT ) ) *
            previousIncrementOfDisplacementVector.at(j);
    }

    //
    // Set-up numerical model
    //
    /* it is not necesary to call numerical method
     * approach used here is not good, but effective enough
     * inverse of diagonal mass matrix is done here
     */
    //
    // call numerical model to solve arised problem - done localy here
    //
#ifdef VERBOSE
    OOFEM_LOG_RELEVANT( "\n\nSolving [Step number %8d, Time %15e]\n", tStep->giveNumber(), tStep->giveTargetTime() );
#endif

    for ( i = 1; i <= neq; i++ ) {
        prevIncrOfDisplacement = previousIncrementOfDisplacementVector.at(i);
        incrOfDisplacement = loadVector.at(i) /
                             ( massMatrix.at(i) * ( 1. / ( deltaT * deltaT ) + dumpingCoef / ( 2. * deltaT ) ) );
        accelerationVector.at(i) = ( incrOfDisplacement - prevIncrOfDisplacement ) / ( deltaT * deltaT );
        velocityVector.at(i)     = ( incrOfDisplacement + prevIncrOfDisplacement ) / ( 2. * deltaT );
        previousIncrementOfDisplacementVector.at(i) = incrOfDisplacement;
    }
}
Esempio n. 14
0
void
NonLinearDynamic :: proceedStep(int di, TimeStep *tStep)
{
    // creates system of governing eq's and solves them at given time step
    // first assemble problem at current time step

    int neq = this->giveNumberOfEquations(EID_MomentumBalance);

    // Time-stepping constants
    double dt2 = deltaT * deltaT;

    if ( tStep->giveTimeDiscretization() == TD_Newmark ) {
        OOFEM_LOG_DEBUG("Solving using Newmark-beta method\n");
        a0 = 1 / ( beta * dt2 );
        a1 = gamma / ( beta * deltaT );
        a2 = 1 / ( beta * deltaT );
        a3 = 1 / ( 2 *  beta ) - 1;
        a4 = ( gamma / beta ) - 1;
        a5 = deltaT / 2 * ( gamma / beta - 2 );
        a6 = 0;
    } else if ( ( tStep->giveTimeDiscretization() == TD_TwoPointBackward ) || ( tStep->giveNumber() == giveNumberOfFirstStep() ) ) {
        if ( tStep->giveTimeDiscretization() != TD_ThreePointBackward ) {
            OOFEM_LOG_DEBUG("Solving using Backward Euler method\n");
        } else {
            OOFEM_LOG_DEBUG("Solving initial step using Three-point Backward Euler method\n");
        }
        a0 = 1 / dt2;
        a1 = 1 / deltaT;
        a2 = 1 / deltaT;
        a3 = 0;
        a4 = 0;
        a5 = 0;
        a6 = 0;
    } else if ( tStep->giveTimeDiscretization() == TD_ThreePointBackward ) {
        OOFEM_LOG_DEBUG("Solving using Three-point Backward Euler method\n");
        a0 = 2 / dt2;
        a1 = 3 / ( 2 * deltaT );
        a2 = 2 / deltaT;
        a3 = 0;
        a4 = 0;
        a5 = 0;
        a6 = 1 / ( 2 * deltaT );
    } else {
        _error("NonLinearDynamic: Time-stepping scheme not found!\n")
    }

    if ( tStep->giveNumber() == giveNumberOfFirstStep() ) {
        // Initialization
        previousIncrementOfDisplacement.resize(neq);
        previousIncrementOfDisplacement.zero();
        previousTotalDisplacement.resize(neq);
        previousTotalDisplacement.zero();
        totalDisplacement.resize(neq);
        totalDisplacement.zero();
        previousInternalForces.resize(neq);
        previousInternalForces.zero();
        incrementOfDisplacement.resize(neq);
        incrementOfDisplacement.zero();
        velocityVector.resize(neq);
        velocityVector.zero();
        accelerationVector.resize(neq);
        accelerationVector.zero();

        TimeStep *stepWhenIcApply = new TimeStep(giveNumberOfTimeStepWhenIcApply(), this, 0,
                                                 -deltaT, deltaT, 0);

        int nDofs, j, k, jj;
        int nman  = this->giveDomain(di)->giveNumberOfDofManagers();
        DofManager *node;
        Dof *iDof;

        // Considering initial conditions.
        for ( j = 1; j <= nman; j++ ) {
            node = this->giveDomain(di)->giveDofManager(j);
            nDofs = node->giveNumberOfDofs();

            for ( k = 1; k <= nDofs; k++ ) {
                // Ask for initial values obtained from
                // bc (boundary conditions) and ic (initial conditions).
                iDof  =  node->giveDof(k);
                if ( !iDof->isPrimaryDof() ) {
                    continue;
                }

                jj = iDof->__giveEquationNumber();
                if ( jj ) {
                    incrementOfDisplacement.at(jj) = iDof->giveUnknown(EID_MomentumBalance, VM_Total, stepWhenIcApply);
                    velocityVector.at(jj) = iDof->giveUnknown(EID_MomentumBalance, VM_Velocity, stepWhenIcApply);
                    accelerationVector.at(jj) = iDof->giveUnknown(EID_MomentumBalance, VM_Acceleration, stepWhenIcApply);
                }
            }
        }
    } else {
        incrementOfDisplacement.resize(neq);
        incrementOfDisplacement.zero();
    }

    if ( initFlag ) {
        // First assemble problem at current time step.
        // Option to take into account initial conditions.
        if ( !stiffnessMatrix ) {
            stiffnessMatrix = CreateUsrDefSparseMtrx(sparseMtrxType);
        }

        if ( stiffnessMatrix == NULL ) {
            _error("proceedStep: sparse matrix creation failed");
        }

        if ( nonlocalStiffnessFlag ) {
            if ( !stiffnessMatrix->isAsymmetric() ) {
                _error("proceedStep: stiffnessMatrix does not support asymmetric storage");
            }
        }

        stiffnessMatrix->buildInternalStructure( this, di, EID_MomentumBalance, EModelDefaultEquationNumbering() );
        // Initialize vectors
        help.resize(neq);
        rhs.resize(neq);
        rhs2.resize(neq);
        internalForces.resize(neq);
        help.zero();
        rhs.zero();
        rhs2.zero();

        previousTotalDisplacement.resize(neq);
        for ( int i = 1; i <= neq; i++ ) {
            previousTotalDisplacement.at(i) = totalDisplacement.at(i);
        }
        initFlag = 0;
    }

#ifdef VERBOSE
    OOFEM_LOG_DEBUG("Assembling load\n");
#endif

    // Assemble the incremental reference load vector.
    this->assembleIncrementalReferenceLoadVectors(incrementalLoadVector, incrementalLoadVectorOfPrescribed,
                                                  refLoadInputMode, this->giveDomain(di), EID_MomentumBalance, tStep);

    // Assembling the effective load vector
    for ( int i = 1; i <= neq; i++ ) {
        help.at(i) = a2 * velocityVector.at(i) + a3 * accelerationVector.at(i)
            + eta * ( a4 * velocityVector.at(i)
                      + a5 * accelerationVector.at(i)
                      + a6 * previousIncrementOfDisplacement.at(i) );
    }

    this->timesMtrx(help, rhs, MassMatrix, this->giveDomain(di), tStep);

    if ( delta != 0 ) {
        for ( int i = 1; i <= neq; i++ ) {
            help.at(i) = delta * ( a4 * velocityVector.at(i)
                                   + a5 * accelerationVector.at(i)
                                   + a6 * previousIncrementOfDisplacement.at(i) );
        }
        this->timesMtrx(help, rhs2, StiffnessMatrix, this->giveDomain(di), tStep);
        help.zero();
        for ( int i = 1; i <= neq; i++ ) {
            rhs.at(i) += rhs2.at(i);
        }
    }

    for ( int i = 1; i <= neq; i++ ) {
        rhs.at(i) += incrementalLoadVector.at(i) - previousInternalForces.at(i);
        totalDisplacement.at(i) = previousTotalDisplacement.at(i);
    }

    //
    // Set-up numerical model.
    //
    this->giveNumericalMethod( this->giveCurrentMetaStep() );

    //
    // Call numerical model to solve problem.
    //
    double loadLevel = 1.0;
    if ( initialLoadVector.isNotEmpty() ) {
        numMetStatus = nMethod->solve(stiffnessMatrix, & rhs, & initialLoadVector,
                                      & totalDisplacement, & incrementOfDisplacement, & internalForces,
                                      internalForcesEBENorm, loadLevel, refLoadInputMode, currentIterations, tStep);
    } else {
        numMetStatus = nMethod->solve(stiffnessMatrix, & rhs, NULL,
                                      & totalDisplacement, & incrementOfDisplacement, & internalForces,
                                      internalForcesEBENorm, loadLevel, refLoadInputMode, currentIterations, tStep);
    }

    OOFEM_LOG_INFO("Equilibrium reached in %d iterations\n", currentIterations);
}
void IncrementalLinearStatic :: solveYourselfAt(TimeStep *tStep)
{
    // Creates system of governing eq's and solves them at given time step

    // Initiates the total displacement to zero.
    if ( tStep->isTheFirstStep() ) {
        Domain *d = this->giveDomain(1);
        for ( int i = 1; i <= d->giveNumberOfDofManagers(); i++ ) {
            DofManager *dofman = d->giveDofManager(i);
            for ( int j = 1; j <= dofman->giveNumberOfDofs(); j++ ) {
                dofman->giveDof(j)->updateUnknownsDictionary(tStep, VM_Total_Old, 0.);
                dofman->giveDof(j)->updateUnknownsDictionary(tStep, VM_Total, 0.);
                // This is actually redundant now;
                //dofman->giveDof(j)->updateUnknownsDictionary(tStep, VM_Incremental, 0.);
            }
        }

	int nbc = d->giveNumberOfBoundaryConditions();
	for ( int ibc = 1; ibc <= nbc; ++ibc ) {
	  GeneralBoundaryCondition *bc = d->giveBc(ibc);
	  ActiveBoundaryCondition *abc;

	  if ( ( abc = dynamic_cast< ActiveBoundaryCondition * >( bc ) ) ) {
	    int ndman = abc->giveNumberOfInternalDofManagers();
	    for ( int i = 1; i <= ndman; i++ ) {
	      DofManager *dofman = abc->giveInternalDofManager(i);
	      for ( int j = 1; j <= dofman->giveNumberOfDofs(); j++ ) {
                dofman->giveDof(j)->updateUnknownsDictionary(tStep, VM_Total_Old, 0.);
                dofman->giveDof(j)->updateUnknownsDictionary(tStep, VM_Total, 0.);
                // This is actually redundant now;
                //dofman->giveDof(j)->updateUnknownsDictionary(tStep, VM_Incremental, 0.);
	      }
	    }
	  }
	}
    }

    // Apply dirichlet b.c's on total values
    Domain *d = this->giveDomain(1);
    for ( int i = 1; i <= d->giveNumberOfDofManagers(); i++ ) {
        DofManager *dofman = d->giveDofManager(i);
        for ( int j = 1; j <= dofman->giveNumberOfDofs(); j++ ) {
            Dof *d = dofman->giveDof(j);
            double tot = d->giveUnknown(VM_Total_Old, tStep);
            if ( d->hasBc(tStep) ) {
                tot += d->giveBcValue(VM_Incremental, tStep);
            }

            d->updateUnknownsDictionary(tStep, VM_Total, tot);
        }
    }


#ifdef VERBOSE
    OOFEM_LOG_RELEVANT( "Solving [step number %8d, time %15e]\n", tStep->giveNumber(), tStep->giveTargetTime() );
#endif

    int neq = this->giveNumberOfDomainEquations(1, EModelDefaultEquationNumbering());

    if (neq == 0) { // Allows for fully prescribed/empty problems.
        return;
    }

    incrementOfDisplacementVector.resize(neq);
    incrementOfDisplacementVector.zero();

#ifdef VERBOSE
    OOFEM_LOG_INFO("Assembling load\n");
#endif
    // Assembling the element part of load vector
    internalLoadVector.resize(neq);
    internalLoadVector.zero();
    this->assembleVector( internalLoadVector, tStep, EID_MomentumBalance, InternalForcesVector,
                          VM_Total, EModelDefaultEquationNumbering(), this->giveDomain(1) );

    loadVector.resize(neq);
    loadVector.zero();
    this->assembleVector( loadVector, tStep, EID_MomentumBalance, ExternalForcesVector,
                          VM_Total, EModelDefaultEquationNumbering(), this->giveDomain(1) );

    loadVector.subtract(internalLoadVector);

#ifdef VERBOSE
    OOFEM_LOG_INFO("Assembling stiffness matrix\n");
#endif
    if ( stiffnessMatrix ) {
        delete stiffnessMatrix;
    }

    stiffnessMatrix = classFactory.createSparseMtrx(sparseMtrxType);
    if ( stiffnessMatrix == NULL ) {
        _error("solveYourselfAt: sparse matrix creation failed");
    }

    stiffnessMatrix->buildInternalStructure( this, 1, EID_MomentumBalance, EModelDefaultEquationNumbering() );
    stiffnessMatrix->zero();
    this->assemble( stiffnessMatrix, tStep, EID_MomentumBalance, StiffnessMatrix,
                   EModelDefaultEquationNumbering(), this->giveDomain(1) );

#ifdef VERBOSE
    OOFEM_LOG_INFO("Solving ...\n");
#endif
    this->giveNumericalMethod( this->giveCurrentMetaStep() );
    NM_Status s = nMethod->solve(stiffnessMatrix, & loadVector, & incrementOfDisplacementVector);
    if ( !(s & NM_Success) ) {
        OOFEM_ERROR("IncrementalLinearStatic :: solverYourselfAt - No success in solving system.");
    }
}