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root/group/trunk/OOPSE/libmdtools/Integrator.cpp
Revision: 1221
Committed: Wed Jun 2 14:56:18 2004 UTC (20 years, 1 month ago) by chrisfen
File size: 18536 byte(s)
Log Message:
Formatting Changes, removed writeRaw

File Contents

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