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root/group/trunk/OOPSE/libmdtools/Integrator.cpp
Revision: 929
Committed: Tue Jan 13 15:46:49 2004 UTC (20 years, 5 months ago) by tim
File size: 17326 byte(s)
Log Message:
 Merge the code of writeFinal and writeDump;
 Adding sortingIndex into DumpWriter;
 Fix a bug of writing last frame twice in integrator

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