VariableTimeStepDirectIntegrationAnalysis.cppGo to the documentation of this file.00001 /* ****************************************************************** ** 00002 ** OpenSees - Open System for Earthquake Engineering Simulation ** 00003 ** Pacific Earthquake Engineering Research Center ** 00004 ** ** 00005 ** ** 00006 ** (C) Copyright 1999, The Regents of the University of California ** 00007 ** All Rights Reserved. ** 00008 ** ** 00009 ** Commercial use of this program without express permission of the ** 00010 ** University of California, Berkeley, is strictly prohibited. See ** 00011 ** file 'COPYRIGHT' in main directory for information on usage and ** 00012 ** redistribution, and for a DISCLAIMER OF ALL WARRANTIES. ** 00013 ** ** 00014 ** Developed by: ** 00015 ** Frank McKenna (fmckenna@ce.berkeley.edu) ** 00016 ** Gregory L. Fenves (fenves@ce.berkeley.edu) ** 00017 ** Filip C. Filippou (filippou@ce.berkeley.edu) ** 00018 ** ** 00019 ** ****************************************************************** */ 00020 00021 // $Revision: 1.5 $ 00022 // $Date: 2005/12/06 18:20:22 $ 00023 // $Source: /usr/local/cvs/OpenSees/SRC/analysis/analysis/VariableTimeStepDirectIntegrationAnalysis.cpp,v $ 00024 00025 00026 // File: ~/analysis/analysis/VariableTimeStepDirectIntegrationAnalysis.C 00027 // 00028 // Written: fmk 00029 // Created: 10/00 00030 // Revision: A 00031 // 00032 // Description: This file contains the implementation of the 00033 // VariableTimeStepDirectIntegrationAnalysis class. 00034 // 00035 // What: "@(#) VariableTimeStepDirectIntegrationAnalysis.C, revA" 00036 00037 #include <VariableTimeStepDirectIntegrationAnalysis.h> 00038 #include <EquiSolnAlgo.h> 00039 #include <TransientIntegrator.h> 00040 #include <Domain.h> 00041 #include <ConvergenceTest.h> 00042 #include <float.h> 00043 00044 // Constructor 00045 VariableTimeStepDirectIntegrationAnalysis::VariableTimeStepDirectIntegrationAnalysis( 00046 Domain &the_Domain, 00047 ConstraintHandler &theHandler, 00048 DOF_Numberer &theNumberer, 00049 AnalysisModel &theModel, 00050 EquiSolnAlgo &theSolnAlgo, 00051 LinearSOE &theLinSOE, 00052 TransientIntegrator &theTransientIntegrator, 00053 ConvergenceTest *theTest) 00054 00055 :DirectIntegrationAnalysis(the_Domain, theHandler, theNumberer, theModel, 00056 theSolnAlgo, theLinSOE, theTransientIntegrator, theTest) 00057 { 00058 00059 } 00060 00061 VariableTimeStepDirectIntegrationAnalysis::~VariableTimeStepDirectIntegrationAnalysis() 00062 { 00063 00064 } 00065 00066 00067 int 00068 VariableTimeStepDirectIntegrationAnalysis::analyze(int numSteps, double dT, double dtMin, double dtMax, int Jd) 00069 { 00070 // get some pointers 00071 Domain *theDom = this->getDomainPtr(); 00072 EquiSolnAlgo *theAlgo = this->getAlgorithm(); 00073 TransientIntegrator *theIntegratr = this->getIntegrator(); 00074 ConvergenceTest *theTest = theAlgo->getConvergenceTest(); 00075 00076 // set some variables 00077 int result = 0; 00078 double totalTimeIncr = numSteps * dT; 00079 double currentTimeIncr = 0.0; 00080 double currentDt = dT; 00081 00082 // loop until analysis has performed the total time incr requested 00083 while (currentTimeIncr < totalTimeIncr) { 00084 00085 if (this->checkDomainChange() != 0) { 00086 opserr << "VariableTimeStepDirectIntegrationAnalysis::analyze() - failed checkDomainChange\n"; 00087 return -1; 00088 } 00089 00090 // 00091 // do newStep(), solveCurrentStep() and commit() as in regular 00092 // DirectINtegrationAnalysis - difference is we do not return 00093 // if a failure - we stop the analysis & resize time step if failure 00094 // 00095 00096 if (theIntegratr->newStep(currentDt) < 0) { 00097 result = -2; 00098 } 00099 00100 if (result >= 0) { 00101 result = theAlgo->solveCurrentStep(); 00102 if (result < 0) 00103 result = -3; 00104 } 00105 00106 if (result >= 0) { 00107 result = theIntegratr->commit(); 00108 if (result < 0) 00109 result = -4; 00110 } 00111 00112 // if the time step was successfull increment delta T for the analysis 00113 // othewise revert the Domain to last committed state & see if can go on 00114 00115 if (result >= 0) 00116 currentTimeIncr += currentDt; 00117 else { 00118 00119 // invoke the revertToLastCommit 00120 theDom->revertToLastCommit(); 00121 theIntegratr->revertToLastStep(); 00122 00123 // if last dT was <= min specified the analysis FAILS - return FAILURE 00124 if (currentDt <= dtMin) { 00125 opserr << "VariableTimeStepDirectIntegrationAnalysis::analyze() - "; 00126 opserr << " failed at time " << theDom->getCurrentTime() << endln; 00127 return result; 00128 } 00129 00130 // if still here reset result for next loop 00131 result = 0; 00132 } 00133 00134 // now we determine a new delta T for next loop 00135 currentDt = this->determineDt(currentDt, dtMin, dtMax, Jd, theTest); 00136 } 00137 00138 return 0; 00139 } 00140 00141 00142 00143 00144 00145 double 00146 VariableTimeStepDirectIntegrationAnalysis::determineDt(double dT, 00147 double dtMin, 00148 double dtMax, 00149 int Jd, 00150 ConvergenceTest *theTest) 00151 { 00152 double newDt = dT; 00153 00154 // get the number of trial steps in the last solveCurrentStep() 00155 double numLastIter = 1.0; 00156 if (theTest != 0) 00157 numLastIter = theTest->getNumTests(); 00158 00159 00160 // determine new dT based on last dT and Jd and #iter of last step 00161 double factor = Jd/numLastIter; 00162 newDt *= factor; 00163 00164 // ensure: dtMin <~~ dT <= dtMax 00165 if (newDt < dtMin) 00166 newDt = dtMin - DBL_EPSILON; // to ensure we get out of the analysis 00167 // loop if can't converge on next step 00168 else if (newDt > dtMax) 00169 newDt = dtMax; 00170 00171 return newDt; 00172 } 00173 00174
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