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Comparing trunk/src/integrators/Velocitizer.cpp (file contents):
Revision 381 by tim, Tue Mar 1 14:45:45 2005 UTC vs.
Revision 1782 by gezelter, Wed Aug 22 02:28:28 2012 UTC

# Line 1 | Line 1
1 < /*
2 < * Copyright (c) 2005 The University of Notre Dame. All Rights Reserved.
3 < *
4 < * The University of Notre Dame grants you ("Licensee") a
5 < * non-exclusive, royalty free, license to use, modify and
6 < * redistribute this software in source and binary code form, provided
7 < * that the following conditions are met:
8 < *
9 < * 1. Acknowledgement of the program authors must be made in any
10 < *    publication of scientific results based in part on use of the
11 < *    program.  An acceptable form of acknowledgement is citation of
12 < *    the article in which the program was described (Matthew
13 < *    A. Meineke, Charles F. Vardeman II, Teng Lin, Christopher
14 < *    J. Fennell and J. Daniel Gezelter, "OOPSE: An Object-Oriented
15 < *    Parallel Simulation Engine for Molecular Dynamics,"
16 < *    J. Comput. Chem. 26, pp. 252-271 (2005))
17 < *
18 < * 2. Redistributions of source code must retain the above copyright
19 < *    notice, this list of conditions and the following disclaimer.
20 < *
21 < * 3. Redistributions in binary form must reproduce the above copyright
22 < *    notice, this list of conditions and the following disclaimer in the
23 < *    documentation and/or other materials provided with the
24 < *    distribution.
25 < *
26 < * This software is provided "AS IS," without a warranty of any
27 < * kind. All express or implied conditions, representations and
28 < * warranties, including any implied warranty of merchantability,
29 < * fitness for a particular purpose or non-infringement, are hereby
30 < * excluded.  The University of Notre Dame and its licensors shall not
31 < * be liable for any damages suffered by licensee as a result of
32 < * using, modifying or distributing the software or its
33 < * derivatives. In no event will the University of Notre Dame or its
34 < * licensors be liable for any lost revenue, profit or data, or for
35 < * direct, indirect, special, consequential, incidental or punitive
36 < * damages, however caused and regardless of the theory of liability,
37 < * arising out of the use of or inability to use software, even if the
38 < * University of Notre Dame has been advised of the possibility of
39 < * such damages.
40 < */
41 <  
42 < #include "integrators/Velocitizer.hpp"
43 < #include "math/SquareMatrix3.hpp"
44 < #include "primitives/Molecule.hpp"
45 < #include "primitives/StuntDouble.hpp"
46 < #include "math/MersenneTwister.hpp"
47 < namespace oopse {
48 <
49 < void Velocitizer::velocitize(double temperature) {
50 <    Vector3d aVel;
51 <    Vector3d aJ;
52 <    Mat3x3d I;
53 <    int l;
54 <    int m;
55 <    int n;
56 <    Vector3d vdrift;
57 <    double vbar;
58 <    /**@todo refactory kb */
59 <    const double kb = 8.31451e-7; // kb in amu, angstroms, fs, etc.
60 <    double av2;
61 <    double kebar;
62 <
63 <    SimInfo::MoleculeIterator i;
64 <    Molecule::IntegrableObjectIterator j;
65 <    Molecule * mol;
66 <    StuntDouble * integrableObject;
67 <
68 <    
69 < #ifndef IS_MPI
70 <    MTRand randNumGen(info_->getSeed());
71 < #else
72 <    int nProcessors;
73 <    MPI_Comm_size(MPI_COMM_WORLD, &nProcessors);
74 <    MTRand randNumGen(info_->getSeed(), nProcessors, worldRank);
75 < #endif
76 <
77 <    kebar = kb * temperature * info_->getNdfRaw() / (2.0 * info_->getNdf());
78 <
79 <    for( mol = info_->beginMolecule(i); mol != NULL;
80 <        mol = info_->nextMolecule(i) ) {
81 <        for( integrableObject = mol->beginIntegrableObject(j);
82 <            integrableObject != NULL;
83 <            integrableObject = mol->nextIntegrableObject(j) ) {
84 <
85 <            // uses equipartition theory to solve for vbar in angstrom/fs
86 <
87 <            av2 = 2.0 * kebar / integrableObject->getMass();
88 <            vbar = sqrt(av2);
89 <
90 <            // picks random velocities from a gaussian distribution
91 <            // centered on vbar
92 <
93 <            for( int k = 0; k < 3; k++ ) {
94 <                aVel[k] = vbar * randNumGen.randNorm(0.0, 1.0);
95 <            }
96 <
97 <            integrableObject->setVel(aVel);
98 <
99 <            if (integrableObject->isDirectional()) {
100 <                I = integrableObject->getI();
101 <
102 <                if (integrableObject->isLinear()) {
103 <                    l = integrableObject->linearAxis();
104 <                    m = (l + 1) % 3;
105 <                    n = (l + 2) % 3;
106 <
107 <                    aJ[l] = 0.0;
108 <                    vbar = sqrt(2.0 * kebar * I(m, m));
109 <                    aJ[m] = vbar * randNumGen.randNorm(0.0, 1.0);
110 <                    vbar = sqrt(2.0 * kebar * I(n, n));
111 <                    aJ[n] = vbar * randNumGen.randNorm(0.0, 1.0);
112 <                } else {
113 <                    for( int k = 0; k < 3; k++ ) {
114 <                        vbar = sqrt(2.0 * kebar * I(k, k));
115 <                        aJ[k] = vbar * randNumGen.randNorm(0.0, 1.0);
116 <                    }
117 <                } // else isLinear
118 <
119 <                integrableObject->setJ(aJ);
120 <            }     //isDirectional
121 <        }
122 <    }             //end for (mol = beginMolecule(i); ...)
123 <
124 <
125 <
126 <    removeComDrift();
127 <
128 < }
129 <
130 <
131 <
132 < void Velocitizer::removeComDrift() {
133 <    // Get the Center of Mass drift velocity.
134 <    Vector3d vdrift = info_->getComVel();
135 <    
136 <    SimInfo::MoleculeIterator i;
137 <    Molecule::IntegrableObjectIterator j;
138 <    Molecule * mol;
139 <    StuntDouble * integrableObject;
140 <    
141 <    //  Corrects for the center of mass drift.
142 <    // sums all the momentum and divides by total mass.
143 <    for( mol = info_->beginMolecule(i); mol != NULL;
144 <        mol = info_->nextMolecule(i) ) {
145 <        for( integrableObject = mol->beginIntegrableObject(j);
146 <            integrableObject != NULL;
147 <            integrableObject = mol->nextIntegrableObject(j) ) {
148 <            integrableObject->setVel(integrableObject->getVel() - vdrift);
149 <        }
150 <    }
151 <
152 < }
153 <
154 < }
1 > /*
2 > * Copyright (c) 2005 The University of Notre Dame. All Rights Reserved.
3 > *
4 > * The University of Notre Dame grants you ("Licensee") a
5 > * non-exclusive, royalty free, license to use, modify and
6 > * redistribute this software in source and binary code form, provided
7 > * that the following conditions are met:
8 > *
9 > * 1. Redistributions of source code must retain the above copyright
10 > *    notice, this list of conditions and the following disclaimer.
11 > *
12 > * 2. Redistributions in binary form must reproduce the above copyright
13 > *    notice, this list of conditions and the following disclaimer in the
14 > *    documentation and/or other materials provided with the
15 > *    distribution.
16 > *
17 > * This software is provided "AS IS," without a warranty of any
18 > * kind. All express or implied conditions, representations and
19 > * warranties, including any implied warranty of merchantability,
20 > * fitness for a particular purpose or non-infringement, are hereby
21 > * excluded.  The University of Notre Dame and its licensors shall not
22 > * be liable for any damages suffered by licensee as a result of
23 > * using, modifying or distributing the software or its
24 > * derivatives. In no event will the University of Notre Dame or its
25 > * licensors be liable for any lost revenue, profit or data, or for
26 > * direct, indirect, special, consequential, incidental or punitive
27 > * damages, however caused and regardless of the theory of liability,
28 > * arising out of the use of or inability to use software, even if the
29 > * University of Notre Dame has been advised of the possibility of
30 > * such damages.
31 > *
32 > * SUPPORT OPEN SCIENCE!  If you use OpenMD or its source code in your
33 > * research, please cite the appropriate papers when you publish your
34 > * work.  Good starting points are:
35 > *                                                                      
36 > * [1]  Meineke, et al., J. Comp. Chem. 26, 252-271 (2005).            
37 > * [2]  Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006).          
38 > * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008).          
39 > * [4]  Kuang & Gezelter,  J. Chem. Phys. 133, 164101 (2010).
40 > * [5]  Vardeman, Stocker & Gezelter, J. Chem. Theory Comput. 7, 834 (2011).
41 > */
42 >
43 > #include "integrators/Velocitizer.hpp"
44 > #include "math/SquareMatrix3.hpp"
45 > #include "primitives/Molecule.hpp"
46 > #include "primitives/StuntDouble.hpp"
47 >
48 > #ifndef IS_MPI
49 > #include "math/SeqRandNumGen.hpp"
50 > #else
51 > #include "math/ParallelRandNumGen.hpp"
52 > #endif
53 >
54 > namespace OpenMD {
55 >  
56 >  Velocitizer::Velocitizer(SimInfo* info) : info_(info), thermo(info) {
57 >    
58 >    int seedValue;
59 >    Globals * simParams = info->getSimParams();
60 >    
61 > #ifndef IS_MPI
62 >    if (simParams->haveSeed()) {
63 >      seedValue = simParams->getSeed();
64 >      randNumGen_ = new SeqRandNumGen(seedValue);
65 >    }else {
66 >      randNumGen_ = new SeqRandNumGen();
67 >    }    
68 > #else
69 >    if (simParams->haveSeed()) {
70 >      seedValue = simParams->getSeed();
71 >      randNumGen_ = new ParallelRandNumGen(seedValue);
72 >    }else {
73 >      randNumGen_ = new ParallelRandNumGen();
74 >    }    
75 > #endif
76 >  }
77 >  
78 >  Velocitizer::~Velocitizer() {
79 >    delete randNumGen_;
80 >  }
81 >  
82 >  void Velocitizer::velocitize(RealType temperature) {
83 >    Vector3d aVel;
84 >    Vector3d aJ;
85 >    Mat3x3d I;
86 >    int l, m, n;
87 >    Vector3d vdrift;
88 >    RealType vbar;
89 >    /**@todo refactor kb */
90 >    const RealType kb = 8.31451e-7; // kb in amu, angstroms, fs, etc.
91 >    RealType av2;
92 >    RealType kebar;
93 >    
94 >    Globals * simParams = info_->getSimParams();
95 >    
96 >    SimInfo::MoleculeIterator i;
97 >    Molecule::IntegrableObjectIterator j;
98 >    Molecule * mol;
99 >    StuntDouble * sd;
100 >
101 >    kebar = kb * temperature * info_->getNdfRaw() / (2.0 * info_->getNdf());
102 >
103 >    for( mol = info_->beginMolecule(i); mol != NULL;
104 >         mol = info_->nextMolecule(i) ) {
105 >
106 >      for( sd = mol->beginIntegrableObject(j); sd != NULL;
107 >           sd = mol->nextIntegrableObject(j) ) {
108 >        
109 >        // uses equipartition theory to solve for vbar in angstrom/fs
110 >        
111 >        av2 = 2.0 * kebar / sd->getMass();
112 >        vbar = sqrt(av2);
113 >        
114 >        // picks random velocities from a gaussian distribution
115 >        // centered on vbar
116 >        
117 >        for( int k = 0; k < 3; k++ ) {
118 >          aVel[k] = vbar * randNumGen_->randNorm(0.0, 1.0);
119 >        }
120 >        sd->setVel(aVel);
121 >        
122 >        if (sd->isDirectional()) {
123 >          I = sd->getI();
124 >          
125 >          if (sd->isLinear()) {
126 >            l = sd->linearAxis();
127 >            m = (l + 1) % 3;
128 >            n = (l + 2) % 3;
129 >            
130 >            aJ[l] = 0.0;
131 >            vbar = sqrt(2.0 * kebar * I(m, m));
132 >            aJ[m] = vbar * randNumGen_->randNorm(0.0, 1.0);
133 >            vbar = sqrt(2.0 * kebar * I(n, n));
134 >            aJ[n] = vbar * randNumGen_->randNorm(0.0, 1.0);
135 >          } else {
136 >            for( int k = 0; k < 3; k++ ) {
137 >              vbar = sqrt(2.0 * kebar * I(k, k));
138 >              aJ[k] = vbar *randNumGen_->randNorm(0.0, 1.0);
139 >            }
140 >          }
141 >          
142 >          sd->setJ(aJ);
143 >        }
144 >      }
145 >    }
146 >        
147 >    removeComDrift();
148 >
149 >    // Remove angular drift if we are not using periodic boundary
150 >    // conditions:
151 >
152 >    if(!simParams->getUsePeriodicBoundaryConditions()) removeAngularDrift();    
153 >  }
154 >    
155 >  void Velocitizer::removeComDrift() {
156 >    // Get the Center of Mass drift velocity.
157 >    Vector3d vdrift = thermo.getComVel();
158 >    
159 >    SimInfo::MoleculeIterator i;
160 >    Molecule::IntegrableObjectIterator j;
161 >    Molecule * mol;
162 >    StuntDouble * sd;
163 >    
164 >    //  Corrects for the center of mass drift.
165 >    // sums all the momentum and divides by total mass.
166 >    for( mol = info_->beginMolecule(i); mol != NULL;
167 >         mol = info_->nextMolecule(i) ) {
168 >
169 >      for( sd = mol->beginIntegrableObject(j); sd != NULL;
170 >           sd = mol->nextIntegrableObject(j) ) {
171 >
172 >        sd->setVel(sd->getVel() - vdrift);
173 >
174 >      }
175 >    }    
176 >  }
177 >    
178 >  void Velocitizer::removeAngularDrift() {
179 >    // Get the Center of Mass drift velocity.
180 >      
181 >    Vector3d vdrift;
182 >    Vector3d com;
183 >      
184 >    thermo.getComAll(com, vdrift);
185 >        
186 >    Mat3x3d inertiaTensor;
187 >    Vector3d angularMomentum;
188 >    Vector3d omega;
189 >              
190 >    thermo.getInertiaTensor(inertiaTensor, angularMomentum);
191 >
192 >    // We now need the inverse of the inertia tensor.
193 >    inertiaTensor = inertiaTensor.inverse();
194 >    omega = inertiaTensor * angularMomentum;
195 >    
196 >    SimInfo::MoleculeIterator i;
197 >    Molecule::IntegrableObjectIterator j;
198 >    Molecule* mol;
199 >    StuntDouble* sd;
200 >    Vector3d tempComPos;
201 >    
202 >    // Corrects for the center of mass angular drift by summing all
203 >    // the angular momentum and dividing by the total mass.
204 >
205 >    for( mol = info_->beginMolecule(i); mol != NULL;
206 >         mol = info_->nextMolecule(i) ) {
207 >
208 >      for( sd = mol->beginIntegrableObject(j); sd != NULL;
209 >           sd = mol->nextIntegrableObject(j) ) {
210 >
211 >        tempComPos = sd->getPos() - com;
212 >        sd->setVel((sd->getVel() - vdrift) - cross(omega, tempComPos));
213 >        
214 >      }
215 >    }  
216 >  }  
217 > }

Comparing trunk/src/integrators/Velocitizer.cpp (property svn:keywords):
Revision 381 by tim, Tue Mar 1 14:45:45 2005 UTC vs.
Revision 1782 by gezelter, Wed Aug 22 02:28:28 2012 UTC

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