src/flucq/FluctuatingChargeConstraints.cpp

/*
 * Copyright (c) 2012 The University of Notre Dame. All Rights Reserved.
 *
 * The University of Notre Dame grants you ("Licensee") a
 * non-exclusive, royalty free, license to use, modify and
 * redistribute this software in source and binary code form, provided
 * that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the
 *    distribution.
 *
 * This software is provided "AS IS," without a warranty of any
 * kind. All express or implied conditions, representations and
 * warranties, including any implied warranty of merchantability,
 * fitness for a particular purpose or non-infringement, are hereby
 * excluded.  The University of Notre Dame and its licensors shall not
 * be liable for any damages suffered by licensee as a result of
 * using, modifying or distributing the software or its
 * derivatives. In no event will the University of Notre Dame or its
 * licensors be liable for any lost revenue, profit or data, or for
 * direct, indirect, special, consequential, incidental or punitive
 * damages, however caused and regardless of the theory of liability,
 * arising out of the use of or inability to use software, even if the
 * University of Notre Dame has been advised of the possibility of
 * such damages.
 *
 * SUPPORT OPEN SCIENCE!  If you use OpenMD or its source code in your
 * research, please cite the appropriate papers when you publish your
 * work.  Good starting points are:
 *                                                                      
 * [1]  Meineke, et al., J. Comp. Chem. 26, 252-271 (2005).             
 * [2]  Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006).          
 * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 234107 (2008).          
 * [4]  Kuang & Gezelter,  J. Chem. Phys. 133, 164101 (2010).
 * [5]  Vardeman, Stocker & Gezelter, J. Chem. Theory Comput. 7, 834 (2011).
 */
 
#include "FluctuatingChargeConstraints.hpp"
#include "primitives/Molecule.hpp"

#ifdef IS_MPI
#include <mpi.h>
#endif

namespace OpenMD {

  FluctuatingChargeConstraints::FluctuatingChargeConstraints(SimInfo* info) : 
    info_(info), constrainRegions_(false), hasFlucQ_(false) {
    
    if (info_->usesFluctuatingCharges()) {
      if (info_->getNFluctuatingCharges() > 0) {
        hasFlucQ_ = true;
      }
    }
  }

  void FluctuatingChargeConstraints::setConstrainRegions(bool cr) {
    constrainRegions_ = cr;
    regionKeys_.clear();
    regionForce_.clear();
    regionCharges_.clear();

    if (constrainRegions_) {
      SimInfo::MoleculeIterator i;
      Molecule* mol;
      int reg;
      std::set<int> regions;      

      for (mol = info_->beginMolecule(i); mol != NULL; 
           mol = info_->nextMolecule(i)) {
        reg = mol->getRegion();
        if (reg >= 0) regions.insert(reg);
        
      }
      for (std::set<int>::iterator r=regions.begin(); r!=regions.end(); ++r) {
        regionKeys_.push_back( (*r) );
      }
      regionForce_.resize( regionKeys_.size() );
      regionCharges_.resize( regionKeys_.size() );
    }
  }


  void FluctuatingChargeConstraints::applyConstraints() {
    if (!hasFlucQ_) return;
    
    SimInfo::MoleculeIterator i;
    Molecule::FluctuatingChargeIterator  j;
    Molecule* mol;
    Atom* atom;
    
    RealType totalFrc, totalMolFrc, regionFrc, constrainedFrc;
    
    // accumulate the total system fluctuating charge forces
    totalFrc = 0.0;
    if (constrainRegions_) {
      std::fill(regionForce_.begin(), regionForce_.end(), 0.0); 
      std::fill(regionCharges_.begin(), regionCharges_.end(), 0); 
    }

    for (mol = info_->beginMolecule(i); mol != NULL; 
         mol = info_->nextMolecule(i)) {

      int region = mol->getRegion();
          
      for (atom = mol->beginFluctuatingCharge(j); atom != NULL;
           atom = mol->nextFluctuatingCharge(j)) {

        RealType frc = atom->getFlucQFrc();
        totalFrc += frc;
        if (constrainRegions_) {
          regionForce_[regionKeys_[region]] += frc;
          regionCharges_[regionKeys_[region]] += 1;
        }
      }
    }

#ifdef IS_MPI
    // in parallel, we need to add up the contributions from all
    // processors:
    MPI::COMM_WORLD.Allreduce(MPI::IN_PLACE, &totalFrc, 1, MPI::REALTYPE, 
                              MPI::SUM);

    if (constrainRegions_) {
      MPI::COMM_WORLD.Allreduce(MPI::IN_PLACE, &regionForce_[0], 
                                regionForce_.size(), MPI::REALTYPE, MPI::SUM);
      MPI::COMM_WORLD.Allreduce(MPI::IN_PLACE, &regionCharges_[0], 
                                regionCharges_.size(), MPI::INT, MPI::SUM);
    }

#endif

    // divide by the total number of fluctuating charges:
    totalFrc /= info_->getNFluctuatingCharges();
    
    // do the same in the regions:
    if (constrainRegions_) {
      for (int i = 0; i < regionForce_.size(); ++i)  {
        regionForce_[ i ] /= regionCharges_[ i ];
      }
    }

    for (mol = info_->beginMolecule(i); mol != NULL; 
         mol = info_->nextMolecule(i)) {     
      
      if (constrainRegions_) {
        int region = mol->getRegion();
        regionFrc = regionForce_[regionKeys_[region]];
      } else {
        regionFrc = 0.0;
      }

      totalMolFrc = 0.0;
      
      // molecular constraints can be done with a second loop.
      if (mol->constrainTotalCharge()) {
        for (atom = mol->beginFluctuatingCharge(j); atom != NULL;
             atom = mol->nextFluctuatingCharge(j)) {
          totalMolFrc += atom->getFlucQFrc();
        }
        totalMolFrc /= mol->getNFluctuatingCharges();
      }

      for (atom = mol->beginFluctuatingCharge(j); atom != NULL;
           atom = mol->nextFluctuatingCharge(j)) {
        //constrainedFrc = atom->getFlucQFrc() - totalFrc - totalMolFrc;

        constrainedFrc = atom->getFlucQFrc() - totalMolFrc;

        if (constrainRegions_) 
          constrainedFrc -= regionFrc;
        
        atom->setFlucQFrc(constrainedFrc);
      }      
    }
  }
}
Revision:	1908
Committed:	Fri Jul 19 21:25:45 2013 UTC (11 years, 9 months ago) by gezelter
File size:	6261 byte(s)
Log Message:	Added infrastructure for region-constrained fluctuating charges.
#	User	Rev	Content
1	gezelter	1740	/*
2			* Copyright (c) 2012 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	gezelter	1879	* [3] Sun, Lin & Gezelter, J. Chem. Phys. 128, 234107 (2008).
39	gezelter	1740	* [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 "FluctuatingChargeConstraints.hpp"
44			#include "primitives/Molecule.hpp"
45
46			#ifdef IS_MPI
47			#include <mpi.h>
48			#endif
49
50			namespace OpenMD {
51
52			FluctuatingChargeConstraints::FluctuatingChargeConstraints(SimInfo* info) :
53	gezelter	1908	info_(info), constrainRegions_(false), hasFlucQ_(false) {
54	gezelter	1740
55			if (info_->usesFluctuatingCharges()) {
56			if (info_->getNFluctuatingCharges() > 0) {
57			hasFlucQ_ = true;
58			}
59			}
60			}
61
62	gezelter	1908	void FluctuatingChargeConstraints::setConstrainRegions(bool cr) {
63			constrainRegions_ = cr;
64			regionKeys_.clear();
65			regionForce_.clear();
66			regionCharges_.clear();
67
68			if (constrainRegions_) {
69			SimInfo::MoleculeIterator i;
70			Molecule* mol;
71			int reg;
72			std::set<int> regions;
73
74			for (mol = info_->beginMolecule(i); mol != NULL;
75			mol = info_->nextMolecule(i)) {
76			reg = mol->getRegion();
77			if (reg >= 0) regions.insert(reg);
78
79			}
80			for (std::set<int>::iterator r=regions.begin(); r!=regions.end(); ++r) {
81			regionKeys_.push_back( (*r) );
82			}
83			regionForce_.resize( regionKeys_.size() );
84			regionCharges_.resize( regionKeys_.size() );
85			}
86			}
87
88
89	gezelter	1740	void FluctuatingChargeConstraints::applyConstraints() {
90			if (!hasFlucQ_) return;
91
92			SimInfo::MoleculeIterator i;
93			Molecule::FluctuatingChargeIterator j;
94			Molecule* mol;
95			Atom* atom;
96
97	gezelter	1908	RealType totalFrc, totalMolFrc, regionFrc, constrainedFrc;
98	gezelter	1740
99			// accumulate the total system fluctuating charge forces
100			totalFrc = 0.0;
101	gezelter	1908	if (constrainRegions_) {
102			std::fill(regionForce_.begin(), regionForce_.end(), 0.0);
103			std::fill(regionCharges_.begin(), regionCharges_.end(), 0);
104			}
105	gezelter	1740
106			for (mol = info_->beginMolecule(i); mol != NULL;
107			mol = info_->nextMolecule(i)) {
108
109	gezelter	1908	int region = mol->getRegion();
110
111	gezelter	1740	for (atom = mol->beginFluctuatingCharge(j); atom != NULL;
112			atom = mol->nextFluctuatingCharge(j)) {
113	gezelter	1908
114			RealType frc = atom->getFlucQFrc();
115			totalFrc += frc;
116			if (constrainRegions_) {
117			regionForce_[regionKeys_[region]] += frc;
118			regionCharges_[regionKeys_[region]] += 1;
119			}
120	gezelter	1740	}
121			}
122
123			#ifdef IS_MPI
124			// in parallel, we need to add up the contributions from all
125			// processors:
126			MPI::COMM_WORLD.Allreduce(MPI::IN_PLACE, &totalFrc, 1, MPI::REALTYPE,
127			MPI::SUM);
128	gezelter	1908
129			if (constrainRegions_) {
130			MPI::COMM_WORLD.Allreduce(MPI::IN_PLACE, &regionForce_[0],
131			regionForce_.size(), MPI::REALTYPE, MPI::SUM);
132			MPI::COMM_WORLD.Allreduce(MPI::IN_PLACE, &regionCharges_[0],
133			regionCharges_.size(), MPI::INT, MPI::SUM);
134			}
135
136	gezelter	1740	#endif
137	gezelter	1908
138	gezelter	1740	// divide by the total number of fluctuating charges:
139			totalFrc /= info_->getNFluctuatingCharges();
140	gezelter	1908
141			// do the same in the regions:
142			if (constrainRegions_) {
143			for (int i = 0; i < regionForce_.size(); ++i) {
144			regionForce_[ i ] /= regionCharges_[ i ];
145			}
146			}
147	gezelter	1740
148			for (mol = info_->beginMolecule(i); mol != NULL;
149			mol = info_->nextMolecule(i)) {
150
151	gezelter	1908	if (constrainRegions_) {
152			int region = mol->getRegion();
153			regionFrc = regionForce_[regionKeys_[region]];
154			} else {
155			regionFrc = 0.0;
156			}
157
158	gezelter	1740	totalMolFrc = 0.0;
159	gezelter	1908
160	gezelter	1740	// molecular constraints can be done with a second loop.
161			if (mol->constrainTotalCharge()) {
162			for (atom = mol->beginFluctuatingCharge(j); atom != NULL;
163			atom = mol->nextFluctuatingCharge(j)) {
164			totalMolFrc += atom->getFlucQFrc();
165			}
166			totalMolFrc /= mol->getNFluctuatingCharges();
167			}
168
169			for (atom = mol->beginFluctuatingCharge(j); atom != NULL;
170			atom = mol->nextFluctuatingCharge(j)) {
171	gezelter	1879	//constrainedFrc = atom->getFlucQFrc() - totalFrc - totalMolFrc;
172	gezelter	1908
173	gezelter	1879	constrainedFrc = atom->getFlucQFrc() - totalMolFrc;
174	gezelter	1908
175			if (constrainRegions_)
176			constrainedFrc -= regionFrc;
177
178	gezelter	1740	atom->setFlucQFrc(constrainedFrc);
179			}
180			}
181			}
182			}