Method formTangent

SRC/analysis/integrator/PFEMIntegrator.cpp:338–388

}

int
PFEMIntegrator::formTangent(int statFlag)
{
    int result = 0;
    statusFlag = statFlag;

    LinearSOE *theLinSOE = this->getLinearSOE();
    AnalysisModel *theModel = this->getAnalysisModel();
    if (theLinSOE == 0 || theModel == 0) {
        opserr << "WARNING TransientIntegrator::formTangent() ";
        opserr << "no LinearSOE or AnalysisModel has been set\n";
        return -1;
    }

    // the loops to form and add the tangents are broken into two for
    // efficiency when performing parallel computations

    theLinSOE->zeroA();

    // do modal damping
    bool inclModalMatrix=theModel->inclModalDampingMatrix();
    if (inclModalMatrix == true) {
        const Vector *modalValues = theModel->getModalDampingFactors();
        if (modalValues != 0) {
            this->addModalDampingMatrix(modalValues);
        }
    }


    // loop through the DOF_Groups and add the unbalance
    DOF_GrpIter &theDOFs = theModel->getDOFs();
    DOF_Group *dofPtr;

    while ((dofPtr = theDOFs()) != 0) {
        if (theLinSOE->addA(dofPtr->getTangent(this),dofPtr->getID()) <0) {
            opserr << "TransientIntegrator::formTangent() - failed to addA:dof\n";
            result = -1;
        }
    }

    // loop through the FE_Elements getting them to add the tangent
    FE_EleIter &theEles2 = theModel->getFEs();
    FE_Element *elePtr;
    while((elePtr = theEles2()) != 0)     {
        if (theLinSOE->addA(elePtr->getTangent(this),elePtr->getID()) < 0) {
            opserr << "TransientIntegrator::formTangent() - failed to addA:ele\n";
            result = -2;
        }
    }
    return result;
}


int PFEMIntegrator::formEleTangent(FE_Element *theEle)