src/integrators/VelocityVerletIntegrator.cpp

/*
 * Copyright (C) 2000-2004  Object Oriented Parallel Simulation Engine (OOPSE) project
 * 
 * Contact: oopse@oopse.org
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1
 * of the License, or (at your option) any later version.
 * All we ask is that proper credit is given for our work, which includes
 * - but is not limited to - adding the above copyright notice to the beginning
 * of your source code files, and to any copyright notice that you may distribute
 * with programs based on this work.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

/**
 * @file VelocityVerletIntegrator.cpp
 * @author tlin
 * @date 11/09/2004
 * @time 16:16am
 * @version 1.0
 */

#include "integrators/VelocityVerletIntegrator.hpp"
#include "integrators/DLM.hpp"

namespace oopse {
VelocityVerletIntegrator::VelocityVerletIntegrator(SimInfo *info) : Integrator(info), rotAlgo(NULL) { 
    dt2 = 0.5 * dt;
    rotAlgo = new DLM();
    rattle = new Rattle(info);
}

VelocityVerletIntegrator::~VelocityVerletIntegrator() { 
    delete rotAlgo;
    delete rattle;
}

void VelocityVerletIntegrator::initialize(){

    // remove center of mass drift velocity (in case we passed in a configuration
    // that was drifting
    velocitizer_->removeComDrift();

    // initialize the forces before the first step
    calcForce(true, true);

    //execute constraint algorithm to make sure at the very beginning the system is constrained  
    if (info_->getNGlobalConstraints() > 0) {
        rattle->constraintA();
        calcForce(true, true);
        rattle->constraintB();        
        info_->getSnapshotManager()->advance();//copy the current snapshot to previous snapshot
    }

    if (needVelocityScaling) {
        velocitizer_->velocitize(targetScalingTemp);
    }
    
    dumpWriter = createDumpWriter();
    statWriter = createStatWriter();

    dumpWriter->writeDump();

    //save statistics, before writeStat,  we must save statistics
    thermo.saveStat();
    saveConservedQuantity();
    statWriter->writeStat(currentSnapshot_->statData);

    currSample = sampleTime + currentSnapshot_->getTime();
    currStatus =  statusTime + currentSnapshot_->getTime();;
    currThermal = thermalTime +  + currentSnapshot_->getTime();
    needPotential = false;
    needStress = false;       
   
}
        
void VelocityVerletIntegrator::doIntegrate() {


    initialize();

    while (currentSnapshot_->getTime() < runTime) {
        
        preStep();

        integrateStep();
        
        postStep();

    }

    finalize();
    
}


void VelocityVerletIntegrator::preStep() {
        double difference = currentSnapshot_->getTime() + dt - currStatus;

        if (difference > 0 || fabs(difference) < oopse::epsilon) {
            needPotential = true;
            needStress = true;   
        }

}

void VelocityVerletIntegrator::postStep() {

        //save snapshot
        info_->getSnapshotManager()->advance();

        //increase time
        currentSnapshot_->increaseTime(dt);        
        
        if (needVelocityScaling) {
            if (currentSnapshot_->getTime() >= currThermal) {
                velocitizer_->velocitize(targetScalingTemp);
                currThermal += thermalTime;
            }
        }

        if (currentSnapshot_->getTime() >= currSample) {
            dumpWriter->writeDump();
            currSample += sampleTime;
        }

        if (currentSnapshot_->getTime() >= currStatus) {
            //save statistics, before writeStat,  we must save statistics
            thermo.saveStat();
            saveConservedQuantity();
            statWriter->writeStat(currentSnapshot_->statData);

            needPotential = false;
            needStress = false;
            currStatus += statusTime;
        }

        
}


void VelocityVerletIntegrator::finalize() {

    dumpWriter->writeDump();

    delete dumpWriter;
    delete statWriter;

    dumpWriter = NULL;
    statWriter = NULL;
    
}

void VelocityVerletIntegrator::integrateStep() { 

    moveA();
    calcForce(needPotential, needStress);
    moveB();
}


void VelocityVerletIntegrator::calcForce(bool needPotential,
                                         bool needStress) { 
    forceMan_->calcForces(needPotential, needStress);
}

DumpWriter* VelocityVerletIntegrator::createDumpWriter() {
    return new DumpWriter(info_, info_->getDumpFileName());
}

StatWriter* VelocityVerletIntegrator::createStatWriter() {
    return new StatWriter(info_->getStatFileName());
}


} //end namespace oopse
Revision:	1910
Committed:	Fri Jan 7 21:50:13 2005 UTC (19 years, 7 months ago) by tim
File size:	5103 byte(s)
Log Message:	ZConstraintForceManager in progress
#	Content
1	/*
2	* Copyright (C) 2000-2004 Object Oriented Parallel Simulation Engine (OOPSE) project
3	*
4	* Contact: oopse@oopse.org
5	*
6	* This program is free software; you can redistribute it and/or
7	* modify it under the terms of the GNU Lesser General Public License
8	* as published by the Free Software Foundation; either version 2.1
9	* of the License, or (at your option) any later version.
10	* All we ask is that proper credit is given for our work, which includes
11	* - but is not limited to - adding the above copyright notice to the beginning
12	* of your source code files, and to any copyright notice that you may distribute
13	* with programs based on this work.
14	*
15	* This program is distributed in the hope that it will be useful,
16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18	* GNU Lesser General Public License for more details.
19	*
20	* You should have received a copy of the GNU Lesser General Public License
21	* along with this program; if not, write to the Free Software
22	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23	*
24	*/
25
26	/**
27	* @file VelocityVerletIntegrator.cpp
28	* @author tlin
29	* @date 11/09/2004
30	* @time 16:16am
31	* @version 1.0
32	*/
33
34	#include "integrators/VelocityVerletIntegrator.hpp"
35	#include "integrators/DLM.hpp"
36
37	namespace oopse {
38	VelocityVerletIntegrator::VelocityVerletIntegrator(SimInfo *info) : Integrator(info), rotAlgo(NULL) {
39	dt2 = 0.5 * dt;
40	rotAlgo = new DLM();
41	rattle = new Rattle(info);
42	}
43
44	VelocityVerletIntegrator::~VelocityVerletIntegrator() {
45	delete rotAlgo;
46	delete rattle;
47	}
48
49	void VelocityVerletIntegrator::initialize(){
50
51	// remove center of mass drift velocity (in case we passed in a configuration
52	// that was drifting
53	velocitizer_->removeComDrift();
54
55	// initialize the forces before the first step
56	calcForce(true, true);
57
58	//execute constraint algorithm to make sure at the very beginning the system is constrained
59	if (info_->getNGlobalConstraints() > 0) {
60	rattle->constraintA();
61	calcForce(true, true);
62	rattle->constraintB();
63	info_->getSnapshotManager()->advance();//copy the current snapshot to previous snapshot
64	}
65
66	if (needVelocityScaling) {
67	velocitizer_->velocitize(targetScalingTemp);
68	}
69
70	dumpWriter = createDumpWriter();
71	statWriter = createStatWriter();
72
73	dumpWriter->writeDump();
74
75	//save statistics, before writeStat, we must save statistics
76	thermo.saveStat();
77	saveConservedQuantity();
78	statWriter->writeStat(currentSnapshot_->statData);
79
80	currSample = sampleTime + currentSnapshot_->getTime();
81	currStatus = statusTime + currentSnapshot_->getTime();;
82	currThermal = thermalTime + + currentSnapshot_->getTime();
83	needPotential = false;
84	needStress = false;
85
86	}
87
88	void VelocityVerletIntegrator::doIntegrate() {
89
90
91	initialize();
92
93	while (currentSnapshot_->getTime() < runTime) {
94
95	preStep();
96
97	integrateStep();
98
99	postStep();
100
101	}
102
103	finalize();
104
105	}
106
107
108	void VelocityVerletIntegrator::preStep() {
109	double difference = currentSnapshot_->getTime() + dt - currStatus;
110
111	if (difference > 0 \|\| fabs(difference) < oopse::epsilon) {
112	needPotential = true;
113	needStress = true;
114	}
115
116	}
117
118	void VelocityVerletIntegrator::postStep() {
119
120	//save snapshot
121	info_->getSnapshotManager()->advance();
122
123	//increase time
124	currentSnapshot_->increaseTime(dt);
125
126	if (needVelocityScaling) {
127	if (currentSnapshot_->getTime() >= currThermal) {
128	velocitizer_->velocitize(targetScalingTemp);
129	currThermal += thermalTime;
130	}
131	}
132
133	if (currentSnapshot_->getTime() >= currSample) {
134	dumpWriter->writeDump();
135	currSample += sampleTime;
136	}
137
138	if (currentSnapshot_->getTime() >= currStatus) {
139	//save statistics, before writeStat, we must save statistics
140	thermo.saveStat();
141	saveConservedQuantity();
142	statWriter->writeStat(currentSnapshot_->statData);
143
144	needPotential = false;
145	needStress = false;
146	currStatus += statusTime;
147	}
148
149
150	}
151
152
153	void VelocityVerletIntegrator::finalize() {
154
155	dumpWriter->writeDump();
156
157	delete dumpWriter;
158	delete statWriter;
159
160	dumpWriter = NULL;
161	statWriter = NULL;
162
163	}
164
165	void VelocityVerletIntegrator::integrateStep() {
166
167	moveA();
168	calcForce(needPotential, needStress);
169	moveB();
170	}
171
172
173	void VelocityVerletIntegrator::calcForce(bool needPotential,
174	bool needStress) {
175	forceMan_->calcForces(needPotential, needStress);
176	}
177
178	DumpWriter* VelocityVerletIntegrator::createDumpWriter() {
179	return new DumpWriter(info_, info_->getDumpFileName());
180	}
181
182	StatWriter* VelocityVerletIntegrator::createStatWriter() {
183	return new StatWriter(info_->getStatFileName());
184	}
185
186
187	} //end namespace oopse