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Comparing trunk/src/primitives/GhostBend.cpp (file contents):
Revision 3 by tim, Fri Sep 24 16:27:58 2004 UTC vs.
Revision 1211 by gezelter, Wed Jan 23 16:38:22 2008 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 "primitives/GhostBend.hpp"
43 + #include "primitives/DirectionalAtom.hpp"
44 + namespace oopse {
45  
46 < #include <math.h>
47 < #include <iostream>
48 < #include <stdlib.h>
5 <
6 < #include "utils/simError.h"
7 < #include "primitives/SRI.hpp"
8 < #include "primitives/Atom.hpp"
9 <
10 <
11 <
12 < GhostBend::GhostBend( Atom &a, Atom &b ){
13 <  
14 <  c_p_a = &a;
15 <  
16 <  if( !b.isDirectional() ){
46 >  /**@todo still a lot left to improve*/
47 >  void GhostBend::calcForce(RealType& angle) {
48 >    DirectionalAtom* ghostAtom = static_cast<DirectionalAtom*>(atom2_);
49      
50 <    // if atom b is not directional, then bad things will happen
50 >    Vector3d pos1 = atom1_->getPos();
51 >    Vector3d pos2 = ghostAtom->getPos();
52      
53 <    sprintf( painCave.errMsg,
54 <             " Ghost Bend error: Atom # %d of type \"%s\" is not "
55 <             "directional.\n",
56 <             b.getIndex(),
57 <             b.getType() );
58 <    painCave.isFatal = 1;
59 <    simError();
60 <  }    
53 >    Vector3d r12 = pos1 - pos2;
54 >    RealType d12 = r12.length();
55 >    
56 >    RealType d12inv = 1.0 / d12;
57 >    
58 >    Vector3d r32 = ghostAtom->getElectroFrame().getColumn(2);
59 >    RealType d32 = r32.length();
60 >    
61 >    RealType d32inv = 1.0 / d32;
62 >    
63 >    RealType cosTheta = dot(r12, r32) / (d12 * d32);
64 >    
65 >    //check roundoff    
66 >    if (cosTheta > 1.0) {
67 >      cosTheta = 1.0;
68 >    } else if (cosTheta < -1.0) {
69 >      cosTheta = -1.0;
70 >    }
71 >    
72 >    RealType theta = acos(cosTheta);
73 >    
74 >    RealType firstDerivative;
75 >    
76 >    bendType_->calcForce(theta, firstDerivative, potential_);
77 >    
78 >    RealType sinTheta = sqrt(1.0 - cosTheta * cosTheta);
79 >    
80 >    if (fabs(sinTheta) < 1.0E-12) {
81 >      sinTheta = 1.0E-12;
82 >    }
83 >    
84 >    RealType commonFactor1 = -firstDerivative / sinTheta * d12inv;
85 >    RealType commonFactor2 = -firstDerivative / sinTheta * d32inv;
86 >    
87 >    Vector3d force1 = commonFactor1*(r12*(d12inv*cosTheta) - r32*d32inv);
88 >    Vector3d force3 = commonFactor2*(r32*(d32inv*cosTheta) - r12*d12inv);
89 >    atom1_->addFrc(force1);
90 >    ghostAtom->addFrc(-force1);
91 >    /**@todo test correctness */
92 >    ghostAtom->addTrq(cross(r32, force3) );
93 >    
94 >    angle = theta /M_PI * 180.0;
95 >    
96 >  }  
97 > } //end namespace oopse
98  
29  atomB = ( DirectionalAtom* ) &b;
30  
31  c_potential_E = 0.0;
32
33 }
34
35
36 void GhostBend::calc_forces(){
37  
38  double dx,dy,dz,gx,gy,gz,dx2,dy2,dz2,gx2,gy2,gz2;
39  double rij2, rkj2, riji2, rkji2, dot, denom, cosang, angl;
40  
41  double sina2, sinai;
42
43  double comf2, comf3, comf4;
44  double dcsidx, dcsidy, dcsidz, dcskdx, dcskdy, dcskdz;
45  // double dcsjdx, dcsjdy, dcsjdz;
46  double dadxi, dadyi, dadzi;
47  double dadxk, dadyk, dadzk;//, dadxj, dadyj, dadzj;
48  double daxi, dayi, dazi, daxk, dayk, dazk, daxj, dayj, dazj;
49  double u[3];
50  
51  double aR[3], bR[3];
52  double aF[3], bF[3], bTrq[3];
53
54  c_p_a->getPos( aR );
55  atomB->getPos( bR );
56  
57
58  dx = aR[0] - bR[0];
59  dy = aR[1] - bR[1];
60  dz = aR[2] - bR[2];
61
62  atomB->getU(u);
63
64  gx = u[0];
65  gy = u[1];
66  gz = u[2];
67  
68  dx2 = dx * dx;
69  dy2 = dy * dy;
70  dz2 = dz * dz;
71
72  gx2 = gx * gx;
73  gy2 = gy * gy;
74  gz2 = gz * gz;
75  
76  rij2 = dx2 + dy2 + dz2;
77  rkj2 = gx2 + gy2 + gz2;
78  
79  riji2 = 1.0 / rij2;
80  rkji2 = 1.0 / rkj2;
81
82  dot = dx * gx + dy * gy + dz * gz;
83  denom = sqrt((riji2 * rkji2));
84  cosang = dot * denom;
85
86  if(cosang > 1.0)cosang = 1.0;
87  if(cosang < -1.0) cosang = -1.0;
88
89  angl = acos(cosang);
90  angl = angl * 180.0 / M_PI;
91
92  sina2 = 1.0 - cosang*cosang;
93  if(fabs(sina2) < 1.0E-12 ) sina2 = 1.0E-12;
94  sinai = 1.0 / sqrt(sina2);
95
96  comf2 = cosang * riji2;
97  comf3 = cosang * rkji2;
98  comf4 = bend_force(angl);
99
100  dcsidx = gx*denom - comf2*dx;
101  dcsidy = gy*denom - comf2*dy;
102  dcsidz = gz*denom - comf2*dz;
103  
104  dcskdx = dx*denom - comf3*gx;
105  dcskdy = dy*denom - comf3*gy;
106  dcskdz = dz*denom - comf3*gz;
107  
108 //   dcsjdx = -dcsidx - dcskdx;
109 //   dcsjdy = -dcsidy - dcskdy;
110 //   dcsjdz = -dcsidz - dcskdz;
111
112  dadxi = -sinai*dcsidx;
113  dadyi = -sinai*dcsidy;
114  dadzi = -sinai*dcsidz;
115
116  dadxk = -sinai*dcskdx;
117  dadyk = -sinai*dcskdy;
118  dadzk = -sinai*dcskdz;
119
120 //   dadxj = -dadxi - dadxk;
121 //   dadyj = -dadyi - dadyk;
122 //   dadzj = -dadzi - dadzk;
123
124  daxi = comf4*dadxi;
125  dayi = comf4*dadyi;
126  dazi = comf4*dadzi;
127
128  daxk = comf4*dadxk;
129  dayk = comf4*dadyk;
130  dazk = comf4*dadzk;
131  
132  daxj = -daxi - daxk;
133  dayj = -dayi - dayk;
134  dazj = -dazi - dazk;
135
136  aF[0] = daxi;
137  aF[1] = dayi;
138  aF[2] = dazi;
139
140  bF[0] = daxj + daxk;
141  bF[1] = dayj + dayk;
142  bF[2] = dazj + dazk;
143
144  bTrq[0] = gy*dazk - gz*dayk;
145  bTrq[1] = gz*daxk - gx*dazk;
146  bTrq[2] = gx*dayk - gy*daxk;
147  
148  
149  c_p_a->addFrc( aF );
150  atomB->addFrc( bF );
151  atomB->addTrq( bTrq );
152  
153  return;
154 }
155
156 void GhostBend::setConstants( double the_c1, double the_c2, double the_c3,
157                                  double the_Th0 ){
158  c1 = the_c1;
159  c2 = the_c2;
160  c3 = the_c3;
161  theta0 = the_Th0;
162 }
163
164
165 double GhostBend::bend_force( double theta ){
166
167  double dt, dt2;
168  double force;
169
170  dt = ( theta - theta0 ) * M_PI / 180.0;
171  dt2 = dt * dt;
172
173  c_potential_E = ( c1 * dt2 ) + ( c2 * dt ) + c3;
174  force = -( ( 2.0 * c1 * dt ) + c2 );
175  return force;
176 }

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