1 |
#include <iostream> |
2 |
#include <stdlib.h> |
3 |
#include <math.h> |
4 |
|
5 |
#ifdef IS_MPI |
6 |
#include "mpiSimulation.hpp" |
7 |
#include <unistd.h> |
8 |
#endif //is_mpi |
9 |
|
10 |
#ifdef PROFILE |
11 |
#include "mdProfile.hpp" |
12 |
#endif // profile |
13 |
|
14 |
#include "Integrator.hpp" |
15 |
#include "simError.h" |
16 |
|
17 |
|
18 |
template<typename T> Integrator<T>::Integrator(SimInfo* theInfo, |
19 |
ForceFields* the_ff){ |
20 |
info = theInfo; |
21 |
myFF = the_ff; |
22 |
isFirst = 1; |
23 |
|
24 |
molecules = info->molecules; |
25 |
nMols = info->n_mol; |
26 |
|
27 |
// give a little love back to the SimInfo object |
28 |
|
29 |
if (info->the_integrator != NULL){ |
30 |
delete info->the_integrator; |
31 |
} |
32 |
|
33 |
nAtoms = info->n_atoms; |
34 |
integrableObjects = info->integrableObjects; |
35 |
|
36 |
// check for constraints |
37 |
|
38 |
constrainedA = NULL; |
39 |
constrainedB = NULL; |
40 |
constrainedDsqr = NULL; |
41 |
moving = NULL; |
42 |
moved = NULL; |
43 |
oldPos = NULL; |
44 |
|
45 |
nConstrained = 0; |
46 |
|
47 |
checkConstraints(); |
48 |
} |
49 |
|
50 |
template<typename T> Integrator<T>::~Integrator(){ |
51 |
if (nConstrained){ |
52 |
delete[] constrainedA; |
53 |
delete[] constrainedB; |
54 |
delete[] constrainedDsqr; |
55 |
delete[] moving; |
56 |
delete[] moved; |
57 |
delete[] oldPos; |
58 |
} |
59 |
} |
60 |
|
61 |
template<typename T> void Integrator<T>::checkConstraints(void){ |
62 |
isConstrained = 0; |
63 |
|
64 |
Constraint* temp_con; |
65 |
Constraint* dummy_plug; |
66 |
temp_con = new Constraint[info->n_SRI]; |
67 |
nConstrained = 0; |
68 |
int constrained = 0; |
69 |
|
70 |
SRI** theArray; |
71 |
for (int i = 0; i < nMols; i++){ |
72 |
|
73 |
theArray = (SRI * *) molecules[i].getMyBonds(); |
74 |
for (int j = 0; j < molecules[i].getNBonds(); j++){ |
75 |
constrained = theArray[j]->is_constrained(); |
76 |
|
77 |
if (constrained){ |
78 |
dummy_plug = theArray[j]->get_constraint(); |
79 |
temp_con[nConstrained].set_a(dummy_plug->get_a()); |
80 |
temp_con[nConstrained].set_b(dummy_plug->get_b()); |
81 |
temp_con[nConstrained].set_dsqr(dummy_plug->get_dsqr()); |
82 |
|
83 |
nConstrained++; |
84 |
constrained = 0; |
85 |
} |
86 |
} |
87 |
|
88 |
theArray = (SRI * *) molecules[i].getMyBends(); |
89 |
for (int j = 0; j < molecules[i].getNBends(); j++){ |
90 |
constrained = theArray[j]->is_constrained(); |
91 |
|
92 |
if (constrained){ |
93 |
dummy_plug = theArray[j]->get_constraint(); |
94 |
temp_con[nConstrained].set_a(dummy_plug->get_a()); |
95 |
temp_con[nConstrained].set_b(dummy_plug->get_b()); |
96 |
temp_con[nConstrained].set_dsqr(dummy_plug->get_dsqr()); |
97 |
|
98 |
nConstrained++; |
99 |
constrained = 0; |
100 |
} |
101 |
} |
102 |
|
103 |
theArray = (SRI * *) molecules[i].getMyTorsions(); |
104 |
for (int j = 0; j < molecules[i].getNTorsions(); j++){ |
105 |
constrained = theArray[j]->is_constrained(); |
106 |
|
107 |
if (constrained){ |
108 |
dummy_plug = theArray[j]->get_constraint(); |
109 |
temp_con[nConstrained].set_a(dummy_plug->get_a()); |
110 |
temp_con[nConstrained].set_b(dummy_plug->get_b()); |
111 |
temp_con[nConstrained].set_dsqr(dummy_plug->get_dsqr()); |
112 |
|
113 |
nConstrained++; |
114 |
constrained = 0; |
115 |
} |
116 |
} |
117 |
} |
118 |
|
119 |
|
120 |
if (nConstrained > 0){ |
121 |
isConstrained = 1; |
122 |
|
123 |
if (constrainedA != NULL) |
124 |
delete[] constrainedA; |
125 |
if (constrainedB != NULL) |
126 |
delete[] constrainedB; |
127 |
if (constrainedDsqr != NULL) |
128 |
delete[] constrainedDsqr; |
129 |
|
130 |
constrainedA = new int[nConstrained]; |
131 |
constrainedB = new int[nConstrained]; |
132 |
constrainedDsqr = new double[nConstrained]; |
133 |
|
134 |
for (int i = 0; i < nConstrained; i++){ |
135 |
constrainedA[i] = temp_con[i].get_a(); |
136 |
constrainedB[i] = temp_con[i].get_b(); |
137 |
constrainedDsqr[i] = temp_con[i].get_dsqr(); |
138 |
} |
139 |
|
140 |
|
141 |
// save oldAtoms to check for lode balancing later on. |
142 |
|
143 |
oldAtoms = nAtoms; |
144 |
|
145 |
moving = new int[nAtoms]; |
146 |
moved = new int[nAtoms]; |
147 |
|
148 |
oldPos = new double[nAtoms * 3]; |
149 |
} |
150 |
|
151 |
delete[] temp_con; |
152 |
} |
153 |
|
154 |
|
155 |
template<typename T> void Integrator<T>::integrate(void){ |
156 |
|
157 |
double runTime = info->run_time; |
158 |
double sampleTime = info->sampleTime; |
159 |
double statusTime = info->statusTime; |
160 |
double thermalTime = info->thermalTime; |
161 |
double resetTime = info->resetTime; |
162 |
|
163 |
double difference; |
164 |
double currSample; |
165 |
double currThermal; |
166 |
double currStatus; |
167 |
double currReset; |
168 |
|
169 |
int calcPot, calcStress; |
170 |
|
171 |
tStats = new Thermo(info); |
172 |
statOut = new StatWriter(info); |
173 |
dumpOut = new DumpWriter(info); |
174 |
|
175 |
atoms = info->atoms; |
176 |
|
177 |
dt = info->dt; |
178 |
dt2 = 0.5 * dt; |
179 |
|
180 |
readyCheck(); |
181 |
|
182 |
// remove center of mass drift velocity (in case we passed in a configuration |
183 |
// that was drifting |
184 |
tStats->removeCOMdrift(); |
185 |
|
186 |
// initialize the forces before the first step |
187 |
|
188 |
calcForce(1, 1); |
189 |
|
190 |
if (nConstrained){ |
191 |
preMove(); |
192 |
constrainA(); |
193 |
calcForce(1, 1); |
194 |
constrainB(); |
195 |
} |
196 |
|
197 |
if (info->setTemp){ |
198 |
thermalize(); |
199 |
} |
200 |
|
201 |
calcPot = 0; |
202 |
calcStress = 0; |
203 |
currSample = sampleTime + info->getTime(); |
204 |
currThermal = thermalTime+ info->getTime(); |
205 |
currStatus = statusTime + info->getTime(); |
206 |
currReset = resetTime + info->getTime(); |
207 |
|
208 |
dumpOut->writeDump(info->getTime()); |
209 |
statOut->writeStat(info->getTime()); |
210 |
|
211 |
|
212 |
#ifdef IS_MPI |
213 |
strcpy(checkPointMsg, "The integrator is ready to go."); |
214 |
MPIcheckPoint(); |
215 |
#endif // is_mpi |
216 |
|
217 |
while (info->getTime() < runTime && !stopIntegrator()){ |
218 |
difference = info->getTime() + dt - currStatus; |
219 |
if (difference > 0 || fabs(difference) < 1e-4 ){ |
220 |
calcPot = 1; |
221 |
calcStress = 1; |
222 |
} |
223 |
|
224 |
#ifdef PROFILE |
225 |
startProfile( pro1 ); |
226 |
#endif |
227 |
|
228 |
integrateStep(calcPot, calcStress); |
229 |
|
230 |
#ifdef PROFILE |
231 |
endProfile( pro1 ); |
232 |
|
233 |
startProfile( pro2 ); |
234 |
#endif // profile |
235 |
|
236 |
info->incrTime(dt); |
237 |
|
238 |
if (info->setTemp){ |
239 |
if (info->getTime() >= currThermal){ |
240 |
thermalize(); |
241 |
currThermal += thermalTime; |
242 |
} |
243 |
} |
244 |
|
245 |
if (info->getTime() >= currSample){ |
246 |
dumpOut->writeDump(info->getTime()); |
247 |
currSample += sampleTime; |
248 |
} |
249 |
|
250 |
if (info->getTime() >= currStatus){ |
251 |
statOut->writeStat(info->getTime()); |
252 |
calcPot = 0; |
253 |
calcStress = 0; |
254 |
currStatus += statusTime; |
255 |
} |
256 |
|
257 |
if (info->resetIntegrator){ |
258 |
if (info->getTime() >= currReset){ |
259 |
this->resetIntegrator(); |
260 |
currReset += resetTime; |
261 |
} |
262 |
} |
263 |
|
264 |
#ifdef PROFILE |
265 |
endProfile( pro2 ); |
266 |
#endif //profile |
267 |
|
268 |
#ifdef IS_MPI |
269 |
strcpy(checkPointMsg, "successfully took a time step."); |
270 |
MPIcheckPoint(); |
271 |
#endif // is_mpi |
272 |
} |
273 |
|
274 |
delete dumpOut; |
275 |
delete statOut; |
276 |
} |
277 |
|
278 |
template<typename T> void Integrator<T>::integrateStep(int calcPot, |
279 |
int calcStress){ |
280 |
// Position full step, and velocity half step |
281 |
|
282 |
#ifdef PROFILE |
283 |
startProfile(pro3); |
284 |
#endif //profile |
285 |
|
286 |
preMove(); |
287 |
|
288 |
#ifdef PROFILE |
289 |
endProfile(pro3); |
290 |
|
291 |
startProfile(pro4); |
292 |
#endif // profile |
293 |
|
294 |
moveA(); |
295 |
|
296 |
#ifdef PROFILE |
297 |
endProfile(pro4); |
298 |
|
299 |
startProfile(pro5); |
300 |
#endif//profile |
301 |
|
302 |
|
303 |
#ifdef IS_MPI |
304 |
strcpy(checkPointMsg, "Succesful moveA\n"); |
305 |
MPIcheckPoint(); |
306 |
#endif // is_mpi |
307 |
|
308 |
|
309 |
// calc forces |
310 |
|
311 |
calcForce(calcPot, calcStress); |
312 |
|
313 |
#ifdef IS_MPI |
314 |
strcpy(checkPointMsg, "Succesful doForces\n"); |
315 |
MPIcheckPoint(); |
316 |
#endif // is_mpi |
317 |
|
318 |
#ifdef PROFILE |
319 |
endProfile( pro5 ); |
320 |
|
321 |
startProfile( pro6 ); |
322 |
#endif //profile |
323 |
|
324 |
// finish the velocity half step |
325 |
|
326 |
moveB(); |
327 |
|
328 |
#ifdef PROFILE |
329 |
endProfile(pro6); |
330 |
#endif // profile |
331 |
|
332 |
#ifdef IS_MPI |
333 |
strcpy(checkPointMsg, "Succesful moveB\n"); |
334 |
MPIcheckPoint(); |
335 |
#endif // is_mpi |
336 |
} |
337 |
|
338 |
|
339 |
template<typename T> void Integrator<T>::moveA(void){ |
340 |
size_t i, j; |
341 |
DirectionalAtom* dAtom; |
342 |
double Tb[3], ji[3]; |
343 |
double vel[3], pos[3], frc[3]; |
344 |
double mass; |
345 |
|
346 |
for (i = 0; i < integrableObjects.size() ; i++){ |
347 |
integrableObjects[i]->getVel(vel); |
348 |
integrableObjects[i]->getPos(pos); |
349 |
integrableObjects[i]->getFrc(frc); |
350 |
|
351 |
mass = integrableObjects[i]->getMass(); |
352 |
|
353 |
for (j = 0; j < 3; j++){ |
354 |
// velocity half step |
355 |
vel[j] += (dt2 * frc[j] / mass) * eConvert; |
356 |
// position whole step |
357 |
pos[j] += dt * vel[j]; |
358 |
} |
359 |
|
360 |
integrableObjects[i]->setVel(vel); |
361 |
integrableObjects[i]->setPos(pos); |
362 |
|
363 |
if (integrableObjects[i]->isDirectional()){ |
364 |
|
365 |
// get and convert the torque to body frame |
366 |
|
367 |
integrableObjects[i]->getTrq(Tb); |
368 |
integrableObjects[i]->lab2Body(Tb); |
369 |
|
370 |
// get the angular momentum, and propagate a half step |
371 |
|
372 |
integrableObjects[i]->getJ(ji); |
373 |
|
374 |
for (j = 0; j < 3; j++) |
375 |
ji[j] += (dt2 * Tb[j]) * eConvert; |
376 |
|
377 |
this->rotationPropagation( integrableObjects[i], ji ); |
378 |
|
379 |
integrableObjects[i]->setJ(ji); |
380 |
} |
381 |
} |
382 |
|
383 |
if (nConstrained){ |
384 |
constrainA(); |
385 |
} |
386 |
} |
387 |
|
388 |
|
389 |
template<typename T> void Integrator<T>::moveB(void){ |
390 |
int i, j; |
391 |
double Tb[3], ji[3]; |
392 |
double vel[3], frc[3]; |
393 |
double mass; |
394 |
|
395 |
for (i = 0; i < integrableObjects.size(); i++){ |
396 |
integrableObjects[i]->getVel(vel); |
397 |
integrableObjects[i]->getFrc(frc); |
398 |
|
399 |
mass = integrableObjects[i]->getMass(); |
400 |
|
401 |
// velocity half step |
402 |
for (j = 0; j < 3; j++) |
403 |
vel[j] += (dt2 * frc[j] / mass) * eConvert; |
404 |
|
405 |
integrableObjects[i]->setVel(vel); |
406 |
|
407 |
if (integrableObjects[i]->isDirectional()){ |
408 |
|
409 |
// get and convert the torque to body frame |
410 |
|
411 |
integrableObjects[i]->getTrq(Tb); |
412 |
integrableObjects[i]->lab2Body(Tb); |
413 |
|
414 |
// get the angular momentum, and propagate a half step |
415 |
|
416 |
integrableObjects[i]->getJ(ji); |
417 |
|
418 |
for (j = 0; j < 3; j++) |
419 |
ji[j] += (dt2 * Tb[j]) * eConvert; |
420 |
|
421 |
|
422 |
integrableObjects[i]->setJ(ji); |
423 |
} |
424 |
} |
425 |
|
426 |
if (nConstrained){ |
427 |
constrainB(); |
428 |
} |
429 |
} |
430 |
|
431 |
template<typename T> void Integrator<T>::preMove(void){ |
432 |
int i, j; |
433 |
double pos[3]; |
434 |
|
435 |
if (nConstrained){ |
436 |
for (i = 0; i < nAtoms; i++){ |
437 |
atoms[i]->getPos(pos); |
438 |
|
439 |
for (j = 0; j < 3; j++){ |
440 |
oldPos[3 * i + j] = pos[j]; |
441 |
} |
442 |
} |
443 |
} |
444 |
} |
445 |
|
446 |
template<typename T> void Integrator<T>::constrainA(){ |
447 |
int i, j; |
448 |
int done; |
449 |
double posA[3], posB[3]; |
450 |
double velA[3], velB[3]; |
451 |
double pab[3]; |
452 |
double rab[3]; |
453 |
int a, b, ax, ay, az, bx, by, bz; |
454 |
double rma, rmb; |
455 |
double dx, dy, dz; |
456 |
double rpab; |
457 |
double rabsq, pabsq, rpabsq; |
458 |
double diffsq; |
459 |
double gab; |
460 |
int iteration; |
461 |
|
462 |
for (i = 0; i < nAtoms; i++){ |
463 |
moving[i] = 0; |
464 |
moved[i] = 1; |
465 |
} |
466 |
|
467 |
iteration = 0; |
468 |
done = 0; |
469 |
while (!done && (iteration < maxIteration)){ |
470 |
done = 1; |
471 |
for (i = 0; i < nConstrained; i++){ |
472 |
a = constrainedA[i]; |
473 |
b = constrainedB[i]; |
474 |
|
475 |
ax = (a * 3) + 0; |
476 |
ay = (a * 3) + 1; |
477 |
az = (a * 3) + 2; |
478 |
|
479 |
bx = (b * 3) + 0; |
480 |
by = (b * 3) + 1; |
481 |
bz = (b * 3) + 2; |
482 |
|
483 |
if (moved[a] || moved[b]){ |
484 |
atoms[a]->getPos(posA); |
485 |
atoms[b]->getPos(posB); |
486 |
|
487 |
for (j = 0; j < 3; j++) |
488 |
pab[j] = posA[j] - posB[j]; |
489 |
|
490 |
//periodic boundary condition |
491 |
|
492 |
info->wrapVector(pab); |
493 |
|
494 |
pabsq = pab[0] * pab[0] + pab[1] * pab[1] + pab[2] * pab[2]; |
495 |
|
496 |
rabsq = constrainedDsqr[i]; |
497 |
diffsq = rabsq - pabsq; |
498 |
|
499 |
// the original rattle code from alan tidesley |
500 |
if (fabs(diffsq) > (tol * rabsq * 2)){ |
501 |
rab[0] = oldPos[ax] - oldPos[bx]; |
502 |
rab[1] = oldPos[ay] - oldPos[by]; |
503 |
rab[2] = oldPos[az] - oldPos[bz]; |
504 |
|
505 |
info->wrapVector(rab); |
506 |
|
507 |
rpab = rab[0] * pab[0] + rab[1] * pab[1] + rab[2] * pab[2]; |
508 |
|
509 |
rpabsq = rpab * rpab; |
510 |
|
511 |
|
512 |
if (rpabsq < (rabsq * -diffsq)){ |
513 |
#ifdef IS_MPI |
514 |
a = atoms[a]->getGlobalIndex(); |
515 |
b = atoms[b]->getGlobalIndex(); |
516 |
#endif //is_mpi |
517 |
sprintf(painCave.errMsg, |
518 |
"Constraint failure in constrainA at atom %d and %d.\n", a, |
519 |
b); |
520 |
painCave.isFatal = 1; |
521 |
simError(); |
522 |
} |
523 |
|
524 |
rma = 1.0 / atoms[a]->getMass(); |
525 |
rmb = 1.0 / atoms[b]->getMass(); |
526 |
|
527 |
gab = diffsq / (2.0 * (rma + rmb) * rpab); |
528 |
|
529 |
dx = rab[0] * gab; |
530 |
dy = rab[1] * gab; |
531 |
dz = rab[2] * gab; |
532 |
|
533 |
posA[0] += rma * dx; |
534 |
posA[1] += rma * dy; |
535 |
posA[2] += rma * dz; |
536 |
|
537 |
atoms[a]->setPos(posA); |
538 |
|
539 |
posB[0] -= rmb * dx; |
540 |
posB[1] -= rmb * dy; |
541 |
posB[2] -= rmb * dz; |
542 |
|
543 |
atoms[b]->setPos(posB); |
544 |
|
545 |
dx = dx / dt; |
546 |
dy = dy / dt; |
547 |
dz = dz / dt; |
548 |
|
549 |
atoms[a]->getVel(velA); |
550 |
|
551 |
velA[0] += rma * dx; |
552 |
velA[1] += rma * dy; |
553 |
velA[2] += rma * dz; |
554 |
|
555 |
atoms[a]->setVel(velA); |
556 |
|
557 |
atoms[b]->getVel(velB); |
558 |
|
559 |
velB[0] -= rmb * dx; |
560 |
velB[1] -= rmb * dy; |
561 |
velB[2] -= rmb * dz; |
562 |
|
563 |
atoms[b]->setVel(velB); |
564 |
|
565 |
moving[a] = 1; |
566 |
moving[b] = 1; |
567 |
done = 0; |
568 |
} |
569 |
} |
570 |
} |
571 |
|
572 |
for (i = 0; i < nAtoms; i++){ |
573 |
moved[i] = moving[i]; |
574 |
moving[i] = 0; |
575 |
} |
576 |
|
577 |
iteration++; |
578 |
} |
579 |
|
580 |
if (!done){ |
581 |
sprintf(painCave.errMsg, |
582 |
"Constraint failure in constrainA, too many iterations: %d\n", |
583 |
iteration); |
584 |
painCave.isFatal = 1; |
585 |
simError(); |
586 |
} |
587 |
|
588 |
} |
589 |
|
590 |
template<typename T> void Integrator<T>::constrainB(void){ |
591 |
int i, j; |
592 |
int done; |
593 |
double posA[3], posB[3]; |
594 |
double velA[3], velB[3]; |
595 |
double vxab, vyab, vzab; |
596 |
double rab[3]; |
597 |
int a, b, ax, ay, az, bx, by, bz; |
598 |
double rma, rmb; |
599 |
double dx, dy, dz; |
600 |
double rvab; |
601 |
double gab; |
602 |
int iteration; |
603 |
|
604 |
for (i = 0; i < nAtoms; i++){ |
605 |
moving[i] = 0; |
606 |
moved[i] = 1; |
607 |
} |
608 |
|
609 |
done = 0; |
610 |
iteration = 0; |
611 |
while (!done && (iteration < maxIteration)){ |
612 |
done = 1; |
613 |
|
614 |
for (i = 0; i < nConstrained; i++){ |
615 |
a = constrainedA[i]; |
616 |
b = constrainedB[i]; |
617 |
|
618 |
ax = (a * 3) + 0; |
619 |
ay = (a * 3) + 1; |
620 |
az = (a * 3) + 2; |
621 |
|
622 |
bx = (b * 3) + 0; |
623 |
by = (b * 3) + 1; |
624 |
bz = (b * 3) + 2; |
625 |
|
626 |
if (moved[a] || moved[b]){ |
627 |
atoms[a]->getVel(velA); |
628 |
atoms[b]->getVel(velB); |
629 |
|
630 |
vxab = velA[0] - velB[0]; |
631 |
vyab = velA[1] - velB[1]; |
632 |
vzab = velA[2] - velB[2]; |
633 |
|
634 |
atoms[a]->getPos(posA); |
635 |
atoms[b]->getPos(posB); |
636 |
|
637 |
for (j = 0; j < 3; j++) |
638 |
rab[j] = posA[j] - posB[j]; |
639 |
|
640 |
info->wrapVector(rab); |
641 |
|
642 |
rma = 1.0 / atoms[a]->getMass(); |
643 |
rmb = 1.0 / atoms[b]->getMass(); |
644 |
|
645 |
rvab = rab[0] * vxab + rab[1] * vyab + rab[2] * vzab; |
646 |
|
647 |
gab = -rvab / ((rma + rmb) * constrainedDsqr[i]); |
648 |
|
649 |
if (fabs(gab) > tol){ |
650 |
dx = rab[0] * gab; |
651 |
dy = rab[1] * gab; |
652 |
dz = rab[2] * gab; |
653 |
|
654 |
velA[0] += rma * dx; |
655 |
velA[1] += rma * dy; |
656 |
velA[2] += rma * dz; |
657 |
|
658 |
atoms[a]->setVel(velA); |
659 |
|
660 |
velB[0] -= rmb * dx; |
661 |
velB[1] -= rmb * dy; |
662 |
velB[2] -= rmb * dz; |
663 |
|
664 |
atoms[b]->setVel(velB); |
665 |
|
666 |
moving[a] = 1; |
667 |
moving[b] = 1; |
668 |
done = 0; |
669 |
} |
670 |
} |
671 |
} |
672 |
|
673 |
for (i = 0; i < nAtoms; i++){ |
674 |
moved[i] = moving[i]; |
675 |
moving[i] = 0; |
676 |
} |
677 |
|
678 |
iteration++; |
679 |
} |
680 |
|
681 |
if (!done){ |
682 |
sprintf(painCave.errMsg, |
683 |
"Constraint failure in constrainB, too many iterations: %d\n", |
684 |
iteration); |
685 |
painCave.isFatal = 1; |
686 |
simError(); |
687 |
} |
688 |
} |
689 |
|
690 |
template<typename T> void Integrator<T>::rotationPropagation |
691 |
( StuntDouble* sd, double ji[3] ){ |
692 |
|
693 |
double angle; |
694 |
double A[3][3], I[3][3]; |
695 |
int i, j, k; |
696 |
|
697 |
// use the angular velocities to propagate the rotation matrix a |
698 |
// full time step |
699 |
|
700 |
sd->getA(A); |
701 |
sd->getI(I); |
702 |
|
703 |
if (sd->isLinear()) { |
704 |
i = sd->linearAxis(); |
705 |
j = (i+1)%3; |
706 |
k = (i+2)%3; |
707 |
|
708 |
angle = dt2 * ji[j] / I[j][j]; |
709 |
this->rotate( k, i, angle, ji, A ); |
710 |
|
711 |
angle = dt * ji[k] / I[k][k]; |
712 |
this->rotate( i, j, angle, ji, A); |
713 |
|
714 |
angle = dt2 * ji[j] / I[j][j]; |
715 |
this->rotate( k, i, angle, ji, A ); |
716 |
|
717 |
} else { |
718 |
// rotate about the x-axis |
719 |
angle = dt2 * ji[0] / I[0][0]; |
720 |
this->rotate( 1, 2, angle, ji, A ); |
721 |
|
722 |
// rotate about the y-axis |
723 |
angle = dt2 * ji[1] / I[1][1]; |
724 |
this->rotate( 2, 0, angle, ji, A ); |
725 |
|
726 |
// rotate about the z-axis |
727 |
angle = dt * ji[2] / I[2][2]; |
728 |
this->rotate( 0, 1, angle, ji, A); |
729 |
|
730 |
// rotate about the y-axis |
731 |
angle = dt2 * ji[1] / I[1][1]; |
732 |
this->rotate( 2, 0, angle, ji, A ); |
733 |
|
734 |
// rotate about the x-axis |
735 |
angle = dt2 * ji[0] / I[0][0]; |
736 |
this->rotate( 1, 2, angle, ji, A ); |
737 |
|
738 |
} |
739 |
sd->setA( A ); |
740 |
} |
741 |
|
742 |
template<typename T> void Integrator<T>::rotate(int axes1, int axes2, |
743 |
double angle, double ji[3], |
744 |
double A[3][3]){ |
745 |
int i, j, k; |
746 |
double sinAngle; |
747 |
double cosAngle; |
748 |
double angleSqr; |
749 |
double angleSqrOver4; |
750 |
double top, bottom; |
751 |
double rot[3][3]; |
752 |
double tempA[3][3]; |
753 |
double tempJ[3]; |
754 |
|
755 |
// initialize the tempA |
756 |
|
757 |
for (i = 0; i < 3; i++){ |
758 |
for (j = 0; j < 3; j++){ |
759 |
tempA[j][i] = A[i][j]; |
760 |
} |
761 |
} |
762 |
|
763 |
// initialize the tempJ |
764 |
|
765 |
for (i = 0; i < 3; i++) |
766 |
tempJ[i] = ji[i]; |
767 |
|
768 |
// initalize rot as a unit matrix |
769 |
|
770 |
rot[0][0] = 1.0; |
771 |
rot[0][1] = 0.0; |
772 |
rot[0][2] = 0.0; |
773 |
|
774 |
rot[1][0] = 0.0; |
775 |
rot[1][1] = 1.0; |
776 |
rot[1][2] = 0.0; |
777 |
|
778 |
rot[2][0] = 0.0; |
779 |
rot[2][1] = 0.0; |
780 |
rot[2][2] = 1.0; |
781 |
|
782 |
// use a small angle aproximation for sin and cosine |
783 |
|
784 |
angleSqr = angle * angle; |
785 |
angleSqrOver4 = angleSqr / 4.0; |
786 |
top = 1.0 - angleSqrOver4; |
787 |
bottom = 1.0 + angleSqrOver4; |
788 |
|
789 |
cosAngle = top / bottom; |
790 |
sinAngle = angle / bottom; |
791 |
|
792 |
rot[axes1][axes1] = cosAngle; |
793 |
rot[axes2][axes2] = cosAngle; |
794 |
|
795 |
rot[axes1][axes2] = sinAngle; |
796 |
rot[axes2][axes1] = -sinAngle; |
797 |
|
798 |
// rotate the momentum acoording to: ji[] = rot[][] * ji[] |
799 |
|
800 |
for (i = 0; i < 3; i++){ |
801 |
ji[i] = 0.0; |
802 |
for (k = 0; k < 3; k++){ |
803 |
ji[i] += rot[i][k] * tempJ[k]; |
804 |
} |
805 |
} |
806 |
|
807 |
// rotate the Rotation matrix acording to: |
808 |
// A[][] = A[][] * transpose(rot[][]) |
809 |
|
810 |
|
811 |
// NOte for as yet unknown reason, we are performing the |
812 |
// calculation as: |
813 |
// transpose(A[][]) = transpose(A[][]) * transpose(rot[][]) |
814 |
|
815 |
for (i = 0; i < 3; i++){ |
816 |
for (j = 0; j < 3; j++){ |
817 |
A[j][i] = 0.0; |
818 |
for (k = 0; k < 3; k++){ |
819 |
A[j][i] += tempA[i][k] * rot[j][k]; |
820 |
} |
821 |
} |
822 |
} |
823 |
} |
824 |
|
825 |
template<typename T> void Integrator<T>::calcForce(int calcPot, int calcStress){ |
826 |
myFF->doForces(calcPot, calcStress); |
827 |
} |
828 |
|
829 |
template<typename T> void Integrator<T>::thermalize(){ |
830 |
tStats->velocitize(); |
831 |
} |
832 |
|
833 |
template<typename T> double Integrator<T>::getConservedQuantity(void){ |
834 |
return tStats->getTotalE(); |
835 |
} |
836 |
template<typename T> string Integrator<T>::getAdditionalParameters(void){ |
837 |
//By default, return a null string |
838 |
//The reason we use string instead of char* is that if we use char*, we will |
839 |
//return a pointer point to local variable which might cause problem |
840 |
return string(); |
841 |
} |