1 |
#include "GridBuilder.hpp" |
2 |
#define PI 3.14159265359 |
3 |
|
4 |
|
5 |
GridBuilder::GridBuilder(RigidBody* rb, int gridWidth) { |
6 |
rbMol = rb; |
7 |
gridwidth = gridWidth; |
8 |
thetaStep = PI / gridwidth; |
9 |
thetaMin = thetaStep / 2.0; |
10 |
phiStep = thetaStep * 2.0; |
11 |
} |
12 |
|
13 |
GridBuilder::~GridBuilder() { |
14 |
} |
15 |
|
16 |
void GridBuilder::launchProbe(int forceField, vector<double> sigmaGrid, |
17 |
vector<double> sGrid, vector<double> epsGrid){ |
18 |
ofstream sigmaOut("sigma.grid"); |
19 |
ofstream sOut("s.grid"); |
20 |
ofstream epsOut("eps.grid"); |
21 |
double startDist; |
22 |
double phiVal; |
23 |
double thetaVal; |
24 |
double sigTemp, sTemp, epsTemp, sigProbe; |
25 |
double minDist = 10.0; //minimum start distance |
26 |
|
27 |
sigList = sigmaGrid; |
28 |
sList = sGrid; |
29 |
epsList = epsGrid; |
30 |
forcefield = forceField; |
31 |
|
32 |
//load the probe atom parameters |
33 |
switch(forcefield){ |
34 |
case 1:{ |
35 |
rparHe = 1.4800; |
36 |
epsHe = -0.021270; |
37 |
}; break; |
38 |
case 2:{ |
39 |
rparHe = 1.14; |
40 |
epsHe = 0.0203; |
41 |
}; break; |
42 |
case 3:{ |
43 |
rparHe = 2.28; |
44 |
epsHe = 0.020269601874; |
45 |
}; break; |
46 |
case 4:{ |
47 |
rparHe = 2.5560; |
48 |
epsHe = 0.0200; |
49 |
}; break; |
50 |
case 5:{ |
51 |
rparHe = 1.14; |
52 |
epsHe = 0.0203; |
53 |
}; break; |
54 |
} |
55 |
|
56 |
if (rparHe < 2.2) |
57 |
sigProbe = 2*rparHe/1.12246204831; |
58 |
else |
59 |
sigProbe = rparHe; |
60 |
|
61 |
//determine the start distance - we always start at least minDist away |
62 |
startDist = rbMol->findMaxExtent() + minDist; |
63 |
if (startDist < minDist) |
64 |
startDist = minDist; |
65 |
|
66 |
//set the initial orientation of the body and loop over theta values |
67 |
|
68 |
for (k =0; k < gridwidth; k++) { |
69 |
thetaVal = thetaMin + k*thetaStep; |
70 |
printf("Theta step %i\n", k); |
71 |
for (j=0; j < gridwidth; j++) { |
72 |
phiVal = j*phiStep; |
73 |
|
74 |
rbMol->setEuler(0.0, thetaVal, phiVal); |
75 |
|
76 |
releaseProbe(startDist); |
77 |
|
78 |
//translate the values to sigma, s, and epsilon of the rigid body |
79 |
sigTemp = 2*sigDist - sigProbe; |
80 |
sTemp = (2*(sDist - sigDist))/(0.122462048309) - sigProbe; |
81 |
epsTemp = pow(epsVal, 2)/fabs(epsHe); |
82 |
|
83 |
sigList.push_back(sigTemp); |
84 |
sList.push_back(sTemp); |
85 |
epsList.push_back(epsTemp); |
86 |
} |
87 |
} |
88 |
} |
89 |
|
90 |
void GridBuilder::releaseProbe(double farPos){ |
91 |
int tooClose; |
92 |
double tempPotEnergy; |
93 |
double interpRange; |
94 |
double interpFrac; |
95 |
|
96 |
probeCoor = farPos; |
97 |
potProgress.clear(); |
98 |
distProgress.clear(); |
99 |
tooClose = 0; |
100 |
epsVal = 0; |
101 |
rhoStep = 0.1; //the distance the probe atom moves between steps |
102 |
|
103 |
while (!tooClose){ |
104 |
calcEnergy(); |
105 |
potProgress.push_back(potEnergy); |
106 |
distProgress.push_back(probeCoor); |
107 |
|
108 |
//if we've reached a new minimum, save the value and position |
109 |
if (potEnergy < epsVal){ |
110 |
epsVal = potEnergy; |
111 |
sDist = probeCoor; |
112 |
} |
113 |
|
114 |
//test if the probe reached the origin - if so, stop stepping closer |
115 |
if (probeCoor < 0){ |
116 |
sigDist = 0.0; |
117 |
tooClose = 1; |
118 |
} |
119 |
|
120 |
//test if the probe beyond the contact point - if not, take a step closer |
121 |
if (potEnergy < 0){ |
122 |
sigDist = probeCoor; |
123 |
tempPotEnergy = potEnergy; |
124 |
probeCoor -= rhoStep; |
125 |
} |
126 |
else { |
127 |
//do a linear interpolation to obtain the sigDist |
128 |
interpRange = potEnergy - tempPotEnergy; |
129 |
interpFrac = potEnergy / interpRange; |
130 |
interpFrac = interpFrac * rhoStep; |
131 |
sigDist = probeCoor + interpFrac; |
132 |
|
133 |
//end the loop |
134 |
tooClose = 1; |
135 |
} |
136 |
} |
137 |
} |
138 |
|
139 |
void GridBuilder::calcEnergy(){ |
140 |
double rXij, rYij, rZij; |
141 |
double rijSquared; |
142 |
double rValSquared, rValPowerSix; |
143 |
double atomRpar, atomEps; |
144 |
double rbAtomPos[3]; |
145 |
|
146 |
potEnergy = 0.0; |
147 |
|
148 |
for(i=0; i<rbMol->getNumAtoms(); i++){ |
149 |
rbMol->getAtomPos(rbAtomPos, i); |
150 |
|
151 |
rXij = rbAtomPos[0]; |
152 |
rYij = rbAtomPos[1]; |
153 |
rZij = rbAtomPos[2] - probeCoor; |
154 |
|
155 |
rijSquared = rXij * rXij + rYij * rYij + rZij * rZij; |
156 |
|
157 |
//in the interest of keeping the code more compact, we are being less |
158 |
//efficient by placing a switch statement in the calculation loop |
159 |
switch(forcefield){ |
160 |
case 1:{ |
161 |
//we are using the CHARMm force field |
162 |
atomRpar = rbMol->getAtomRpar(i); |
163 |
atomEps = rbMol->getAtomEps(i); |
164 |
|
165 |
rValSquared = ((rparHe+atomRpar)*(rparHe+atomRpar)) / (rijSquared); |
166 |
rValPowerSix = rValSquared * rValSquared * rValSquared; |
167 |
potEnergy += sqrt(epsHe*atomEps)*(rValPowerSix * (rValPowerSix - 2.0)); |
168 |
}; break; |
169 |
|
170 |
case 2:{ |
171 |
//we are using the AMBER force field |
172 |
atomRpar = rbMol->getAtomRpar(i); |
173 |
atomEps = rbMol->getAtomEps(i); |
174 |
|
175 |
rValSquared = ((rparHe+atomRpar)*(rparHe+atomRpar)) / (rijSquared); |
176 |
rValPowerSix = rValSquared * rValSquared * rValSquared; |
177 |
potEnergy += sqrt(epsHe*atomEps)*(rValPowerSix * (rValPowerSix - 2.0)); |
178 |
}; break; |
179 |
|
180 |
case 3:{ |
181 |
//we are using Allen-Tildesley LJ parameters |
182 |
atomRpar = rbMol->getAtomRpar(i); |
183 |
atomEps = rbMol->getAtomEps(i); |
184 |
|
185 |
rValSquared = ((rparHe+atomRpar)*(rparHe+atomRpar)) / (4*rijSquared); |
186 |
rValPowerSix = rValSquared * rValSquared * rValSquared; |
187 |
potEnergy += 4*sqrt(epsHe*atomEps)*(rValPowerSix * (rValPowerSix - 1.0)); |
188 |
|
189 |
}; break; |
190 |
|
191 |
case 4:{ |
192 |
//we are using the OPLS force field |
193 |
atomRpar = rbMol->getAtomRpar(i); |
194 |
atomEps = rbMol->getAtomEps(i); |
195 |
|
196 |
rValSquared = (pow(sqrt(rparHe+atomRpar),2)) / (rijSquared); |
197 |
rValPowerSix = rValSquared * rValSquared * rValSquared; |
198 |
potEnergy += 4*sqrt(epsHe*atomEps)*(rValPowerSix * (rValPowerSix - 1.0)); |
199 |
}; break; |
200 |
|
201 |
case 5:{ |
202 |
//we are using the GAFF force field |
203 |
atomRpar = rbMol->getAtomRpar(i); |
204 |
atomEps = rbMol->getAtomEps(i); |
205 |
|
206 |
rValSquared = ((rparHe+atomRpar)*(rparHe+atomRpar)) / (rijSquared); |
207 |
rValPowerSix = rValSquared * rValSquared * rValSquared; |
208 |
potEnergy += sqrt(epsHe*atomEps)*(rValPowerSix * (rValPowerSix - 2.0)); |
209 |
}; break; |
210 |
} |
211 |
} |
212 |
} |
213 |
|
214 |
void GridBuilder::printGridFiles(){ |
215 |
ofstream sigmaOut("sigma.grid"); |
216 |
ofstream sOut("s.grid"); |
217 |
ofstream epsOut("eps.grid"); |
218 |
|
219 |
for (k=0; k<sigList.size(); k++){ |
220 |
sigmaOut << sigList[k] << "\n0\n"; |
221 |
sOut << sList[k] << "\n0\n"; |
222 |
epsOut << epsList[k] << "\n0\n"; |
223 |
} |
224 |
} |
225 |
|