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CentralDifferenceAlternative.cpp Go to the documentation of this file. /* ****************************************************************** ** ** OpenSees - Open System for Earthquake Engineering Simulation ** ** Pacific Earthquake Engineering Research Center ** ** ** ** ** ** (C) Copyright 1999, The Regents of the University of California ** ** All Rights Reserved. ** ** ** ** Commercial use of this program without express permission of the ** ** University of California, Berkeley, is strictly prohibited. See ** ** file 'COPYRIGHT' in main directory for information on usage and ** ** redistribution, and for a DISCLAIMER OF ALL WARRANTIES. ** ** ** ** Developed by: ** ** Frank McKenna (fmckenna@ce.berkeley.edu) ** ** Gregory L. Fenves (fenves@ce.berkeley.edu) ** ** Filip C. Filippou (filippou@ce.berkeley.edu) ** ** ** ** ****************************************************************** */ // $Revision: 1.2 $ // $Date: 2006/02/28 19:34:01 $ // $Source: /usr/local/cvs/OpenSees/SRC/analysis/integrator/CentralDifferenceAlternative.cpp,v $ // Written: fmk // Created: 11/98 // Revision: A // // Description: This file contains the implementation of the CentralDifferenceAlternative // class. // // What: "@(#) CentralDifferenceAlternative.C, revA" #include <CentralDifferenceAlternative.h> #include <FE_Element.h> #include <LinearSOE.h> #include <AnalysisModel.h> #include <Vector.h> #include <DOF_Group.h> #include <DOF_GrpIter.h> #include <AnalysisModel.h> #include <Channel.h> #include <FEM_ObjectBroker.h> CentralDifferenceAlternative::CentralDifferenceAlternative() :TransientIntegrator(INTEGRATOR_TAGS_CentralDifferenceAlternative), updateCount(0), Ut(0), Utp1(0), Udot(0), deltaT(0) { } CentralDifferenceAlternative::~CentralDifferenceAlternative() { // clean up the memory created if (Ut != 0) delete Ut; if (Utp1 != 0) delete Utp1; if (Udot != 0) delete Udot; } int CentralDifferenceAlternative::newStep(double _deltaT) { updateCount = 0; deltaT = _deltaT; if (deltaT <= 0.0) { opserr << "CentralDifference::newStep() - error in variable\n"; opserr << "dT = " << deltaT << endln; return -2; } AnalysisModel *theModel = this->getAnalysisModelPtr(); double time = theModel->getCurrentDomainTime(); theModel->applyLoadDomain(time); return 0; } int CentralDifferenceAlternative::formEleTangent(FE_Element *theEle) { theEle->zeroTangent(); theEle->addMtoTang(); return 0; } int CentralDifferenceAlternative::formNodTangent(DOF_Group *theDof) { theDof->zeroTangent(); theDof->addMtoTang(); return(0); } int CentralDifferenceAlternative::domainChanged() { AnalysisModel *myModel = this->getAnalysisModelPtr(); LinearSOE *theLinSOE = this->getLinearSOEPtr(); const Vector &x = theLinSOE->getX(); int size = x.Size(); // create the new Vector objects if (Ut == 0 || Ut->Size() != size) { // delete the old if (Ut != 0) delete Ut; if (Utp1 != 0) delete Utp1; if (Udot != 0) delete Udot; // create the new Ut = new Vector(size); Utp1 = new Vector(size); Udot = new Vector(size); // cheack we obtained the new if (Ut == 0 || Ut->Size() != size || Utp1 == 0 || Utp1->Size() != size || Udot == 0 || Udot->Size() != size) { opserr << "CentralDifferenceAlternative::domainChanged - ran out of memory\n"; // delete the old if (Ut != 0) delete Ut; if (Utp1 != 0) delete Utp1; if (Udot != 0) delete Udot; Ut = 0; Utp1 = 0; Udot = 0; return -1; } } // now go through and populate U and Udot by iterating through // the DOF_Groups and getting the last committed velocity and accel DOF_GrpIter &theDOFs = myModel->getDOFs(); DOF_Group *dofPtr; while ((dofPtr = theDOFs()) != 0) { const ID &id = dofPtr->getID(); int idSize = id.Size(); int i; const Vector &disp = dofPtr->getCommittedDisp(); for (i=0; i < idSize; i++) { int loc = id(i); if (loc >= 0) { (*Ut)(loc) = disp(i); } } const Vector &vel = dofPtr->getCommittedVel(); for (i=0; i < idSize; i++) { int loc = id(i); if (loc >= 0) { (*Udot)(loc) = vel(i); } } } return 0; } int CentralDifferenceAlternative::update(const Vector &X) { updateCount++; if (updateCount > 1) { opserr << "ERROR CentralDifferenceAlternative::update() - called more than once -"; opserr << " Central Difference integraion schemes require a LINEAR solution algorithm\n"; return -1; } AnalysisModel *theModel = this->getAnalysisModelPtr(); if (theModel == 0) { opserr << "ERROR CentralDifferenceAlternative::update() - no AnalysisModel set\n"; return -2; } // check domainChanged() has been called, i.e. Ut will not be zero if (Ut == 0) { opserr << "WARNING CentralDifferenceAlternative::update() - domainChange() failed or not called\n"; return -2; } // check deltaU is of correct size if (X.Size() != Ut->Size()) { opserr << "WARNING CentralDifferenceAlternative::update() - Vectors of incompatable size "; opserr << " expecting " << Ut->Size() << " obtained " << X.Size() << endln; return -3; } // determine the displacement at t+delta t Utp1->addVector(0.0, X, deltaT * deltaT); (*Utp1) += *Ut; Utp1->addVector(1.0, *Udot, deltaT); // determine the vel at t+ 0.5 * delta t (*Udot) = *Utp1; (*Udot) -= *Ut; (*Udot) *= (1.0/deltaT); // update the disp & responses at the DOFs theModel->setDisp(*Utp1); theModel->setVel(*Udot); theModel->updateDomain(); return 0; } int CentralDifferenceAlternative::commit(void) { AnalysisModel *theModel = this->getAnalysisModelPtr(); if (theModel == 0) { opserr << "WARNING CentralDifferenceAlternative::commit() - no AnalysisModel set\n"; return -1; } *Ut = *Utp1; // update time in Domain to T + deltaT & commit the domain double time = theModel->getCurrentDomainTime() + deltaT; theModel->setCurrentDomainTime(time); return theModel->commitDomain(); return 0; } int CentralDifferenceAlternative::sendSelf(int cTag, Channel &theChannel) { return 0; } int CentralDifferenceAlternative::recvSelf(int cTag, Channel &theChannel, FEM_ObjectBroker &theBroker) { return 0; } void CentralDifferenceAlternative::Print(OPS_Stream &s, int flag) { AnalysisModel *theModel = this->getAnalysisModelPtr(); if (theModel != 0) { double currentTime = theModel->getCurrentDomainTime(); s << "\t CentralDifferenceAlternative - currentTime: " << currentTime; } else s << "\t CentralDifferenceAlternative - no associated AnalysisModel\n"; } Generated on Mon Oct 23 15:04:58 2006 for OpenSees by  1.5.0

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