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root/group/trunk/OOPSE/libmdtools/Integrator.cpp
Revision: 829
Committed: Tue Oct 28 16:03:37 2003 UTC (20 years, 8 months ago) by gezelter
File size: 16556 byte(s)
Log Message:
replace c++ header stuff with more portable c header stuff
Also, mod file fixes and portability changes
Some fortran changes will need to be reversed.

File Contents

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