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root/group/trunk/OOPSE/libmdtools/Integrator.cpp
Revision: 1452
Committed: Mon Aug 23 15:11:36 2004 UTC (19 years, 10 months ago) by tim
File size: 21290 byte(s)
Log Message:
*** empty log message ***

File Contents

# Content
1 #include <iostream>
2 #include <stdlib.h>
3 #include <math.h>
4 #include "Rattle.hpp"
5 #include "Roll.hpp"
6 #ifdef IS_MPI
7 #include "mpiSimulation.hpp"
8 #include <unistd.h>
9 #endif //is_mpi
10
11 #ifdef PROFILE
12 #include "mdProfile.hpp"
13 #endif // profile
14
15 #include "Integrator.hpp"
16 #include "simError.h"
17
18
19 template<typename T> Integrator<T>::Integrator(SimInfo* theInfo,
20 ForceFields* the_ff){
21 info = theInfo;
22 myFF = the_ff;
23 isFirst = 1;
24
25 molecules = info->molecules;
26 nMols = info->n_mol;
27
28 // give a little love back to the SimInfo object
29
30 if (info->the_integrator != NULL){
31 delete info->the_integrator;
32 }
33
34 nAtoms = info->n_atoms;
35 integrableObjects = info->integrableObjects;
36
37 consFramework = new RollFramework(info);
38
39 if(consFramework == NULL){
40 sprintf(painCave.errMsg,
41 "Integrator::Intergrator() Error: Memory allocation error for RattleFramework" );
42 painCave.isFatal = 1;
43 simError();
44 }
45
46 /*
47 // check for constraints
48
49 constrainedA = NULL;
50 constrainedB = NULL;
51 constrainedDsqr = NULL;
52 moving = NULL;
53 moved = NULL;
54 oldPos = NULL;
55
56 nConstrained = 0;
57
58 checkConstraints();
59 */
60 }
61
62 template<typename T> Integrator<T>::~Integrator(){
63 if (consFramework != NULL)
64 delete consFramework;
65 /*
66 if (nConstrained){
67 delete[] constrainedA;
68 delete[] constrainedB;
69 delete[] constrainedDsqr;
70 delete[] moving;
71 delete[] moved;
72 delete[] oldPos;
73 }
74 */
75 }
76
77 /*
78 template<typename T> void Integrator<T>::checkConstraints(void){
79 isConstrained = 0;
80
81 Constraint* temp_con;
82 Constraint* dummy_plug;
83 temp_con = new Constraint[info->n_SRI];
84 nConstrained = 0;
85 int constrained = 0;
86
87 SRI** theArray;
88 for (int i = 0; i < nMols; i++){
89
90 theArray = (SRI * *) molecules[i].getMyBonds();
91 for (int j = 0; j < molecules[i].getNBonds(); j++){
92 constrained = theArray[j]->is_constrained();
93
94 if (constrained){
95 dummy_plug = theArray[j]->get_constraint();
96 temp_con[nConstrained].set_a(dummy_plug->get_a());
97 temp_con[nConstrained].set_b(dummy_plug->get_b());
98 temp_con[nConstrained].set_dsqr(dummy_plug->get_dsqr());
99
100 nConstrained++;
101 constrained = 0;
102 }
103 }
104
105 theArray = (SRI * *) molecules[i].getMyBends();
106 for (int j = 0; j < molecules[i].getNBends(); j++){
107 constrained = theArray[j]->is_constrained();
108
109 if (constrained){
110 dummy_plug = theArray[j]->get_constraint();
111 temp_con[nConstrained].set_a(dummy_plug->get_a());
112 temp_con[nConstrained].set_b(Dummy_plug->get_b());
113 temp_con[nConstrained].set_dsqr(dummy_plug->get_dsqr());
114
115 nConstrained++;
116 constrained = 0;
117 }
118 }
119
120 theArray = (SRI * *) molecules[i].getMyTorsions();
121 for (int j = 0; j < molecules[i].getNTorsions(); j++){
122 constrained = theArray[j]->is_constrained();
123
124 if (constrained){
125 dummy_plug = theArray[j]->get_constraint();
126 temp_con[nConstrained].set_a(dummy_plug->get_a());
127 temp_con[nConstrained].set_b(dummy_plug->get_b());
128 temp_con[nConstrained].set_dsqr(dummy_plug->get_dsqr());
129
130 nConstrained++;
131 constrained = 0;
132 }
133 }
134 }
135
136
137 if (nConstrained > 0){
138 isConstrained = 1;
139
140 if (constrainedA != NULL)
141 delete[] constrainedA;
142 if (constrainedB != NULL)
143 delete[] constrainedB;
144 if (constrainedDsqr != NULL)
145 delete[] constrainedDsqr;
146
147 constrainedA = new int[nConstrained];
148 constrainedB = new int[nConstrained];
149 constrainedDsqr = new double[nConstrained];
150
151 for (int i = 0; i < nConstrained; i++){
152 constrainedA[i] = temp_con[i].get_a();
153 constrainedB[i] = temp_con[i].get_b();
154 constrainedDsqr[i] = temp_con[i].get_dsqr();
155 }
156
157
158 // save oldAtoms to check for lode balancing later on.
159
160 oldAtoms = nAtoms;
161
162 moving = new int[nAtoms];
163 moved = new int[nAtoms];
164
165 oldPos = new double[nAtoms * 3];
166 }
167
168 delete[] temp_con;
169 }
170 */
171
172 template<typename T> void Integrator<T>::integrate(void){
173
174 double runTime = info->run_time;
175 double sampleTime = info->sampleTime;
176 double statusTime = info->statusTime;
177 double thermalTime = info->thermalTime;
178 double resetTime = info->resetTime;
179
180 double difference;
181 double currSample;
182 double currThermal;
183 double currStatus;
184 double currReset;
185
186 int calcPot, calcStress;
187
188 tStats = new Thermo(info);
189 statOut = new StatWriter(info);
190 dumpOut = new DumpWriter(info);
191
192 atoms = info->atoms;
193
194 dt = info->dt;
195 dt2 = 0.5 * dt;
196
197 readyCheck();
198
199 // remove center of mass drift velocity (in case we passed in a configuration
200 // that was drifting
201 tStats->removeCOMdrift();
202 //tStats->removeAngularMomentum();
203
204 // initialize the retraints if necessary
205 if (info->useSolidThermInt && !info->useLiquidThermInt) {
206 myFF->initRestraints();
207 }
208
209 // initialize the forces before the first step
210
211 calcForce(1, 1);
212
213 //execute constraint algorithm to make sure at the very beginning the system is constrained
214 //consFramework->doPreConstraint();
215 //consFramework->doConstrainA();
216 //calcForce(1, 1);
217 //consFramework->doConstrainB();
218
219 if (info->setTemp){
220 thermalize();
221 }
222
223 calcPot = 0;
224 calcStress = 0;
225 currSample = sampleTime + info->getTime();
226 currThermal = thermalTime+ info->getTime();
227 currStatus = statusTime + info->getTime();
228 currReset = resetTime + info->getTime();
229
230 dumpOut->writeDump(info->getTime());
231 statOut->writeStat(info->getTime());
232
233
234 #ifdef IS_MPI
235 strcpy(checkPointMsg, "The integrator is ready to go.");
236 MPIcheckPoint();
237 #endif // is_mpi
238
239 while (info->getTime() < runTime && !stopIntegrator()){
240 difference = info->getTime() + dt - currStatus;
241 if (difference > 0 || fabs(difference) < 1e-4 ){
242 calcPot = 1;
243 calcStress = 1;
244 }
245
246 #ifdef PROFILE
247 startProfile( pro1 );
248 #endif
249
250 integrateStep(calcPot, calcStress);
251
252 #ifdef PROFILE
253 endProfile( pro1 );
254
255 startProfile( pro2 );
256 #endif // profile
257
258 info->incrTime(dt);
259
260 if (info->setTemp){
261 if (info->getTime() >= currThermal){
262 thermalize();
263 currThermal += thermalTime;
264 }
265 }
266
267 if (info->getTime() >= currSample){
268 dumpOut->writeDump(info->getTime());
269 currSample += sampleTime;
270 }
271
272 if (info->getTime() >= currStatus){
273 statOut->writeStat(info->getTime());
274 calcPot = 0;
275 calcStress = 0;
276 currStatus += statusTime;
277 }
278
279 if (info->resetIntegrator){
280 if (info->getTime() >= currReset){
281 this->resetIntegrator();
282 currReset += resetTime;
283 }
284 }
285
286 #ifdef PROFILE
287 endProfile( pro2 );
288 #endif //profile
289
290 #ifdef IS_MPI
291 strcpy(checkPointMsg, "successfully took a time step.");
292 MPIcheckPoint();
293 #endif // is_mpi
294 }
295
296 // dump out a file containing the omega values for the final configuration
297 if (info->useSolidThermInt && !info->useLiquidThermInt)
298 myFF->dumpzAngle();
299
300
301 delete dumpOut;
302 delete statOut;
303 }
304
305 template<typename T> void Integrator<T>::integrateStep(int calcPot,
306 int calcStress){
307 // Position full step, and velocity half step
308
309 #ifdef PROFILE
310 startProfile(pro3);
311 #endif //profile
312
313 //save old state (position, velocity etc)
314 consFramework->doPreConstraint();
315
316 #ifdef PROFILE
317 endProfile(pro3);
318
319 startProfile(pro4);
320 #endif // profile
321
322 moveA();
323
324 #ifdef PROFILE
325 endProfile(pro4);
326
327 startProfile(pro5);
328 #endif//profile
329
330
331 #ifdef IS_MPI
332 strcpy(checkPointMsg, "Succesful moveA\n");
333 MPIcheckPoint();
334 #endif // is_mpi
335
336 // calc forces
337 calcForce(calcPot, calcStress);
338
339 #ifdef IS_MPI
340 strcpy(checkPointMsg, "Succesful doForces\n");
341 MPIcheckPoint();
342 #endif // is_mpi
343
344 #ifdef PROFILE
345 endProfile( pro5 );
346
347 startProfile( pro6 );
348 #endif //profile
349
350 consFramework->doPreConstraint();
351
352 // finish the velocity half step
353
354 moveB();
355
356 #ifdef PROFILE
357 endProfile(pro6);
358 #endif // profile
359
360 #ifdef IS_MPI
361 strcpy(checkPointMsg, "Succesful moveB\n");
362 MPIcheckPoint();
363 #endif // is_mpi
364 }
365
366
367 template<typename T> void Integrator<T>::moveA(void){
368 size_t i, j;
369 DirectionalAtom* dAtom;
370 double Tb[3], ji[3];
371 double vel[3], pos[3], frc[3];
372 double mass;
373 double omega;
374
375 for (i = 0; i < integrableObjects.size() ; i++){
376 integrableObjects[i]->getVel(vel);
377 integrableObjects[i]->getPos(pos);
378 integrableObjects[i]->getFrc(frc);
379
380 mass = integrableObjects[i]->getMass();
381
382 for (j = 0; j < 3; j++){
383 // velocity half step
384 vel[j] += (dt2 * frc[j] / mass) * eConvert;
385 // position whole step
386 pos[j] += dt * vel[j];
387 }
388
389 integrableObjects[i]->setVel(vel);
390 integrableObjects[i]->setPos(pos);
391
392 if (integrableObjects[i]->isDirectional()){
393
394 // get and convert the torque to body frame
395
396 integrableObjects[i]->getTrq(Tb);
397 integrableObjects[i]->lab2Body(Tb);
398
399 // get the angular momentum, and propagate a half step
400
401 integrableObjects[i]->getJ(ji);
402
403 for (j = 0; j < 3; j++)
404 ji[j] += (dt2 * Tb[j]) * eConvert;
405
406 this->rotationPropagation( integrableObjects[i], ji );
407
408 integrableObjects[i]->setJ(ji);
409
410 }
411 }
412
413 consFramework->doConstrainA();
414 }
415
416
417 template<typename T> void Integrator<T>::moveB(void){
418 int i, j;
419 double Tb[3], ji[3];
420 double vel[3], frc[3];
421 double mass;
422
423 for (i = 0; i < integrableObjects.size(); i++){
424 integrableObjects[i]->getVel(vel);
425 integrableObjects[i]->getFrc(frc);
426
427 mass = integrableObjects[i]->getMass();
428
429 // velocity half step
430 for (j = 0; j < 3; j++)
431 vel[j] += (dt2 * frc[j] / mass) * eConvert;
432
433 integrableObjects[i]->setVel(vel);
434
435 if (integrableObjects[i]->isDirectional()){
436
437 // get and convert the torque to body frame
438
439 integrableObjects[i]->getTrq(Tb);
440 integrableObjects[i]->lab2Body(Tb);
441
442 // get the angular momentum, and propagate a half step
443
444 integrableObjects[i]->getJ(ji);
445
446 for (j = 0; j < 3; j++)
447 ji[j] += (dt2 * Tb[j]) * eConvert;
448
449
450 integrableObjects[i]->setJ(ji);
451 }
452
453 }
454
455 consFramework->doConstrainB();
456 }
457
458 /*
459 template<typename T> void Integrator<T>::preMove(void){
460 int i, j;
461 double pos[3];
462
463 if (nConstrained){
464 for (i = 0; i < nAtoms; i++){
465 atoms[i]->getPos(pos);
466
467 for (j = 0; j < 3; j++){
468 oldPos[3 * i + j] = pos[j];
469 }
470 }
471 }
472 }
473
474 template<typename T> void Integrator<T>::constrainA(){
475 int i, j;
476 int done;
477 double posA[3], posB[3];
478 double velA[3], velB[3];
479 double pab[3];
480 double rab[3];
481 int a, b, ax, ay, az, bx, by, bz;
482 double rma, rmb;
483 double dx, dy, dz;
484 double rpab;
485 double rabsq, pabsq, rpabsq;
486 double diffsq;
487 double gab;
488 int iteration;
489
490 for (i = 0; i < nAtoms; i++){
491 moving[i] = 0;
492 moved[i] = 1;
493 }
494
495 iteration = 0;
496 done = 0;
497 while (!done && (iteration < maxIteration)){
498 done = 1;
499 for (i = 0; i < nConstrained; i++){
500 a = constrainedA[i];
501 b = constrainedB[i];
502
503 ax = (a * 3) + 0;
504 ay = (a * 3) + 1;
505 az = (a * 3) + 2;
506
507 bx = (b * 3) + 0;
508 by = (b * 3) + 1;
509 bz = (b * 3) + 2;
510
511 if (moved[a] || moved[b]){
512 atoms[a]->getPos(posA);
513 atoms[b]->getPos(posB);
514
515 for (j = 0; j < 3; j++)
516 pab[j] = posA[j] - posB[j];
517
518 //periodic boundary condition
519
520 info->wrapVector(pab);
521
522 pabsq = pab[0] * pab[0] + pab[1] * pab[1] + pab[2] * pab[2];
523
524 rabsq = constrainedDsqr[i];
525 diffsq = rabsq - pabsq;
526
527 // the original rattle code from alan tidesley
528 if (fabs(diffsq) > (tol * rabsq * 2)){
529 rab[0] = oldPos[ax] - oldPos[bx];
530 rab[1] = oldPos[ay] - oldPos[by];
531 rab[2] = oldPos[az] - oldPos[bz];
532
533 info->wrapVector(rab);
534
535 rpab = rab[0] * pab[0] + rab[1] * pab[1] + rab[2] * pab[2];
536
537 rpabsq = rpab * rpab;
538
539
540 if (rpabsq < (rabsq * -diffsq)){
541 #ifdef IS_MPI
542 a = atoms[a]->getGlobalIndex();
543 b = atoms[b]->getGlobalIndex();
544 #endif //is_mpi
545 sprintf(painCave.errMsg,
546 "Constraint failure in constrainA at atom %d and %d.\n", a,
547 b);
548 painCave.isFatal = 1;
549 simError();
550 }
551
552 rma = 1.0 / atoms[a]->getMass();
553 rmb = 1.0 / atoms[b]->getMass();
554
555 gab = diffsq / (2.0 * (rma + rmb) * rpab);
556
557 dx = rab[0] * gab;
558 dy = rab[1] * gab;
559 dz = rab[2] * gab;
560
561 posA[0] += rma * dx;
562 posA[1] += rma * dy;
563 posA[2] += rma * dz;
564
565 atoms[a]->setPos(posA);
566
567 posB[0] -= rmb * dx;
568 posB[1] -= rmb * dy;
569 posB[2] -= rmb * dz;
570
571 atoms[b]->setPos(posB);
572
573 dx = dx / dt;
574 dy = dy / dt;
575 dz = dz / dt;
576
577 atoms[a]->getVel(velA);
578
579 velA[0] += rma * dx;
580 velA[1] += rma * dy;
581 velA[2] += rma * dz;
582
583 atoms[a]->setVel(velA);
584
585 atoms[b]->getVel(velB);
586
587 velB[0] -= rmb * dx;
588 velB[1] -= rmb * dy;
589 velB[2] -= rmb * dz;
590
591 atoms[b]->setVel(velB);
592
593 moving[a] = 1;
594 moving[b] = 1;
595 done = 0;
596 }
597 }
598 }
599
600 for (i = 0; i < nAtoms; i++){
601 moved[i] = moving[i];
602 moving[i] = 0;
603 }
604
605 iteration++;
606 }
607
608 if (!done){
609 sprintf(painCave.errMsg,
610 "Constraint failure in constrainA, too many iterations: %d\n",
611 iteration);
612 painCave.isFatal = 1;
613 simError();
614 }
615
616 }
617
618 template<typename T> void Integrator<T>::constrainB(void){
619 int i, j;
620 int done;
621 double posA[3], posB[3];
622 double velA[3], velB[3];
623 double vxab, vyab, vzab;
624 double rab[3];
625 int a, b, ax, ay, az, bx, by, bz;
626 double rma, rmb;
627 double dx, dy, dz;
628 double rvab;
629 double gab;
630 int iteration;
631
632 for (i = 0; i < nAtoms; i++){
633 moving[i] = 0;
634 moved[i] = 1;
635 }
636
637 done = 0;
638 iteration = 0;
639 while (!done && (iteration < maxIteration)){
640 done = 1;
641
642 for (i = 0; i < nConstrained; i++){
643 a = constrainedA[i];
644 b = constrainedB[i];
645
646 ax = (a * 3) + 0;
647 ay = (a * 3) + 1;
648 az = (a * 3) + 2;
649
650 bx = (b * 3) + 0;
651 by = (b * 3) + 1;
652 bz = (b * 3) + 2;
653
654 if (moved[a] || moved[b]){
655 atoms[a]->getVel(velA);
656 atoms[b]->getVel(velB);
657
658 vxab = velA[0] - velB[0];
659 vyab = velA[1] - velB[1];
660 vzab = velA[2] - velB[2];
661
662 atoms[a]->getPos(posA);
663 atoms[b]->getPos(posB);
664
665 for (j = 0; j < 3; j++)
666 rab[j] = posA[j] - posB[j];
667
668 info->wrapVector(rab);
669
670 rma = 1.0 / atoms[a]->getMass();
671 rmb = 1.0 / atoms[b]->getMass();
672
673 rvab = rab[0] * vxab + rab[1] * vyab + rab[2] * vzab;
674
675 gab = -rvab / ((rma + rmb) * constrainedDsqr[i]);
676
677 if (fabs(gab) > tol){
678 dx = rab[0] * gab;
679 dy = rab[1] * gab;
680 dz = rab[2] * gab;
681
682 velA[0] += rma * dx;
683 velA[1] += rma * dy;
684 velA[2] += rma * dz;
685
686 atoms[a]->setVel(velA);
687
688 velB[0] -= rmb * dx;
689 velB[1] -= rmb * dy;
690 velB[2] -= rmb * dz;
691
692 atoms[b]->setVel(velB);
693
694 moving[a] = 1;
695 moving[b] = 1;
696 done = 0;
697 }
698 }
699 }
700
701 for (i = 0; i < nAtoms; i++){
702 moved[i] = moving[i];
703 moving[i] = 0;
704 }
705
706 iteration++;
707 }
708
709 if (!done){
710 sprintf(painCave.errMsg,
711 "Constraint failure in constrainB, too many iterations: %d\n",
712 iteration);
713 painCave.isFatal = 1;
714 simError();
715 }
716 }
717 */
718 template<typename T> void Integrator<T>::rotationPropagation
719 ( StuntDouble* sd, double ji[3] ){
720
721 double angle;
722 double A[3][3], I[3][3];
723 int i, j, k;
724
725 // use the angular velocities to propagate the rotation matrix a
726 // full time step
727
728 sd->getA(A);
729 sd->getI(I);
730
731 if (sd->isLinear()) {
732 i = sd->linearAxis();
733 j = (i+1)%3;
734 k = (i+2)%3;
735
736 angle = dt2 * ji[j] / I[j][j];
737 this->rotate( k, i, angle, ji, A );
738
739 angle = dt * ji[k] / I[k][k];
740 this->rotate( i, j, angle, ji, A);
741
742 angle = dt2 * ji[j] / I[j][j];
743 this->rotate( k, i, angle, ji, A );
744
745 } else {
746 // rotate about the x-axis
747 angle = dt2 * ji[0] / I[0][0];
748 this->rotate( 1, 2, angle, ji, A );
749
750 // rotate about the y-axis
751 angle = dt2 * ji[1] / I[1][1];
752 this->rotate( 2, 0, angle, ji, A );
753
754 // rotate about the z-axis
755 angle = dt * ji[2] / I[2][2];
756 sd->addZangle(angle);
757 this->rotate( 0, 1, angle, ji, A);
758
759 // rotate about the y-axis
760 angle = dt2 * ji[1] / I[1][1];
761 this->rotate( 2, 0, angle, ji, A );
762
763 // rotate about the x-axis
764 angle = dt2 * ji[0] / I[0][0];
765 this->rotate( 1, 2, angle, ji, A );
766
767 }
768 sd->setA( A );
769 }
770
771 template<typename T> void Integrator<T>::rotate(int axes1, int axes2,
772 double angle, double ji[3],
773 double A[3][3]){
774 int i, j, k;
775 double sinAngle;
776 double cosAngle;
777 double angleSqr;
778 double angleSqrOver4;
779 double top, bottom;
780 double rot[3][3];
781 double tempA[3][3];
782 double tempJ[3];
783
784 // initialize the tempA
785
786 for (i = 0; i < 3; i++){
787 for (j = 0; j < 3; j++){
788 tempA[j][i] = A[i][j];
789 }
790 }
791
792 // initialize the tempJ
793
794 for (i = 0; i < 3; i++)
795 tempJ[i] = ji[i];
796
797 // initalize rot as a unit matrix
798
799 rot[0][0] = 1.0;
800 rot[0][1] = 0.0;
801 rot[0][2] = 0.0;
802
803 rot[1][0] = 0.0;
804 rot[1][1] = 1.0;
805 rot[1][2] = 0.0;
806
807 rot[2][0] = 0.0;
808 rot[2][1] = 0.0;
809 rot[2][2] = 1.0;
810
811 // use a small angle aproximation for sin and cosine
812
813 angleSqr = angle * angle;
814 angleSqrOver4 = angleSqr / 4.0;
815 top = 1.0 - angleSqrOver4;
816 bottom = 1.0 + angleSqrOver4;
817
818 cosAngle = top / bottom;
819 sinAngle = angle / bottom;
820
821 rot[axes1][axes1] = cosAngle;
822 rot[axes2][axes2] = cosAngle;
823
824 rot[axes1][axes2] = sinAngle;
825 rot[axes2][axes1] = -sinAngle;
826
827 // rotate the momentum acoording to: ji[] = rot[][] * ji[]
828
829 for (i = 0; i < 3; i++){
830 ji[i] = 0.0;
831 for (k = 0; k < 3; k++){
832 ji[i] += rot[i][k] * tempJ[k];
833 }
834 }
835
836 // rotate the Rotation matrix acording to:
837 // A[][] = A[][] * transpose(rot[][])
838
839
840 // NOte for as yet unknown reason, we are performing the
841 // calculation as:
842 // transpose(A[][]) = transpose(A[][]) * transpose(rot[][])
843
844 for (i = 0; i < 3; i++){
845 for (j = 0; j < 3; j++){
846 A[j][i] = 0.0;
847 for (k = 0; k < 3; k++){
848 A[j][i] += tempA[i][k] * rot[j][k];
849 }
850 }
851 }
852 }
853
854 template<typename T> void Integrator<T>::calcForce(int calcPot, int calcStress){
855 myFF->doForces(calcPot, calcStress);
856 }
857
858 template<typename T> void Integrator<T>::thermalize(){
859 tStats->velocitize();
860 }
861
862 template<typename T> double Integrator<T>::getConservedQuantity(void){
863 return tStats->getTotalE();
864 }
865 template<typename T> string Integrator<T>::getAdditionalParameters(void){
866 //By default, return a null string
867 //The reason we use string instead of char* is that if we use char*, we will
868 //return a pointer point to local variable which might cause problem
869 return string();
870 }
871
872
873 template<typename T> void Integrator<T>::printQuaternion(StuntDouble* sd){
874 Mat4x4d S;
875 double I[3][3];
876 Vector4d j4;
877 Vector3d j;
878 Vector3d tempJ;
879 Vector4d qdot;
880 Vector4d omega4;
881 Mat4x4d I4;
882 Quaternion q;
883 double I0;
884 Vector4d p_qua;
885
886 if (sd->isDirectional()){
887 sd->getQ(q.vec);
888 sd->getI(I);
889 sd->getJ(j.vec);
890
891 //omega4[0] = 0.0;
892 //omega4[1] = j[0]/I[0][0];
893 //omega4[2] = j[1]/I[1][1];
894 //omega4[3] = j[2]/I[2][2];
895
896 //S = getS(q);
897 //qdot = 0.5 * S * omega4;
898
899 //I0 = (qdot[1] * q[1] * I[0][0] + qdot[2] * q[2] * I[1][1] + qdot[3] * q[3] * I[2][2])/(qdot[1] * q[1]+ qdot[2] * q[2] + qdot[3] * q[3]);
900
901 //I4.element[0][0] = I0;
902 //I4.element[1][1] = I[0][0];
903 //I4.element[2][2] = I[1][1];
904 //I4.element[3][3] = I[2][2];
905
906 S = getS(q);
907 j4[0] = 0.0;
908 j4[1] = j[0];
909 j4[2] = j[1];
910 j4[3] = j[2];
911
912 p_qua = 2 * S * j4;
913
914 j4 = 0.5 * S.transpose() * p_qua;
915 //cout << "q0^2 + q1^2 + q2^2 + q3^2 = " << q[0]*q[0] + q[1]*q[1] + q[2]*q[2] + q[3]*q[3] << endl;
916 //cout << "q0*q0dot + q1*q1dot + q2 *q2dot + q3*q3dot = " <<q[0]*qdot[0] + q[1]*qdot[1] + q[2]*qdot[2] + q[3]*qdot[3] << endl;
917 //cout << "q1*q1dot* Ixx + q2*q2dot* Iyy + q3 *q3dot* Izz = " << qdot[1] * q[1] * I[0][0] + qdot[2] * q[2] * I[1][1] + qdot[3] * q[3] * I[2][2] << endl;
918 //cout << "q1*q1dot + q2 *q2dot + q3*q3dot = " << qdot[1] * q[1]+ qdot[2] * q[2] + qdot[3] * q[3] << endl;
919 //cout << "I0 = " << I0 << endl;
920 cout << "p_qua[0] = " << p_qua[0] << endl;
921 }
922 }
923
924 template<typename T> Mat4x4d Integrator<T>::getS(const Quaternion& q){
925 Mat4x4d result;
926
927 result.element[0][0] = q.x;
928 result.element[0][1] = -q.y;
929 result.element[0][2] = -q.z;
930 result.element[0][3] = -q.w;
931
932 result.element[1][0] = q.y;
933 result.element[1][1] = q.x;
934 result.element[1][2] = -q.w;
935 result.element[1][3] = q.z;
936
937 result.element[2][0] = q.z;
938 result.element[2][1] = q.w;
939 result.element[2][2] = q.x;
940 result.element[2][3] = -q.y;
941
942 result.element[3][0] = q.w;
943 result.element[3][1] = -q.z;
944 result.element[3][2] = q.y;
945 result.element[3][3] = q.x;
946
947 return result;
948 }
949