| 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 |  | 
| 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 | if ((info->getTime() + dt) >= currStatus){ | 
| 219 | calcPot = 1; | 
| 220 | calcStress = 1; | 
| 221 | } | 
| 222 |  | 
| 223 | #ifdef PROFILE | 
| 224 | startProfile( pro1 ); | 
| 225 | #endif | 
| 226 |  | 
| 227 | integrateStep(calcPot, calcStress); | 
| 228 |  | 
| 229 | #ifdef PROFILE | 
| 230 | endProfile( pro1 ); | 
| 231 |  | 
| 232 | startProfile( pro2 ); | 
| 233 | #endif // profile | 
| 234 |  | 
| 235 | info->incrTime(dt); | 
| 236 |  | 
| 237 | if (info->setTemp){ | 
| 238 | if (info->getTime() >= currThermal){ | 
| 239 | thermalize(); | 
| 240 | currThermal += thermalTime; | 
| 241 | } | 
| 242 | } | 
| 243 |  | 
| 244 | if (info->getTime() >= currSample){ | 
| 245 | dumpOut->writeDump(info->getTime()); | 
| 246 | currSample += sampleTime; | 
| 247 | } | 
| 248 |  | 
| 249 | if (info->getTime() >= currStatus){ | 
| 250 | statOut->writeStat(info->getTime()); | 
| 251 | calcPot = 0; | 
| 252 | calcStress = 0; | 
| 253 | currStatus += statusTime; | 
| 254 | } | 
| 255 |  | 
| 256 | if (info->resetIntegrator){ | 
| 257 | if (info->getTime() >= currReset){ | 
| 258 | this->resetIntegrator(); | 
| 259 | currReset += resetTime; | 
| 260 | } | 
| 261 | } | 
| 262 |  | 
| 263 | #ifdef PROFILE | 
| 264 | endProfile( pro2 ); | 
| 265 | #endif //profile | 
| 266 |  | 
| 267 | #ifdef IS_MPI | 
| 268 | strcpy(checkPointMsg, "successfully took a time step."); | 
| 269 | MPIcheckPoint(); | 
| 270 | #endif // is_mpi | 
| 271 | } | 
| 272 |  | 
| 273 | delete dumpOut; | 
| 274 | delete statOut; | 
| 275 | } | 
| 276 |  | 
| 277 | template<typename T> void Integrator<T>::integrateStep(int calcPot, | 
| 278 | int calcStress){ | 
| 279 | // Position full step, and velocity half step | 
| 280 |  | 
| 281 | #ifdef PROFILE | 
| 282 | startProfile(pro3); | 
| 283 | #endif //profile | 
| 284 |  | 
| 285 | preMove(); | 
| 286 |  | 
| 287 | #ifdef PROFILE | 
| 288 | endProfile(pro3); | 
| 289 |  | 
| 290 | startProfile(pro4); | 
| 291 | #endif // profile | 
| 292 |  | 
| 293 | moveA(); | 
| 294 |  | 
| 295 | #ifdef PROFILE | 
| 296 | endProfile(pro4); | 
| 297 |  | 
| 298 | startProfile(pro5); | 
| 299 | #endif//profile | 
| 300 |  | 
| 301 |  | 
| 302 | #ifdef IS_MPI | 
| 303 | strcpy(checkPointMsg, "Succesful moveA\n"); | 
| 304 | MPIcheckPoint(); | 
| 305 | #endif // is_mpi | 
| 306 |  | 
| 307 |  | 
| 308 | // calc forces | 
| 309 |  | 
| 310 | calcForce(calcPot, calcStress); | 
| 311 |  | 
| 312 | #ifdef IS_MPI | 
| 313 | strcpy(checkPointMsg, "Succesful doForces\n"); | 
| 314 | MPIcheckPoint(); | 
| 315 | #endif // is_mpi | 
| 316 |  | 
| 317 | #ifdef PROFILE | 
| 318 | endProfile( pro5 ); | 
| 319 |  | 
| 320 | startProfile( pro6 ); | 
| 321 | #endif //profile | 
| 322 |  | 
| 323 | // finish the velocity  half step | 
| 324 |  | 
| 325 | moveB(); | 
| 326 |  | 
| 327 | #ifdef PROFILE | 
| 328 | endProfile(pro6); | 
| 329 | #endif // profile | 
| 330 |  | 
| 331 | #ifdef IS_MPI | 
| 332 | strcpy(checkPointMsg, "Succesful moveB\n"); | 
| 333 | MPIcheckPoint(); | 
| 334 | #endif // is_mpi | 
| 335 | } | 
| 336 |  | 
| 337 |  | 
| 338 | template<typename T> void Integrator<T>::moveA(void){ | 
| 339 | size_t i, j; | 
| 340 | DirectionalAtom* dAtom; | 
| 341 | double Tb[3], ji[3]; | 
| 342 | double vel[3], pos[3], frc[3]; | 
| 343 | double mass; | 
| 344 |  | 
| 345 | for (i = 0; i < integrableObjects.size() ; i++){ | 
| 346 | integrableObjects[i]->getVel(vel); | 
| 347 | integrableObjects[i]->getPos(pos); | 
| 348 | integrableObjects[i]->getFrc(frc); | 
| 349 |  | 
| 350 | std::cerr << "i =\t" << i << "\t" << frc[0] << "\t" << frc[1]<< "\t" << frc[2] << "\n"; | 
| 351 |  | 
| 352 | mass = integrableObjects[i]->getMass(); | 
| 353 |  | 
| 354 | for (j = 0; j < 3; j++){ | 
| 355 | // velocity half step | 
| 356 | vel[j] += (dt2 * frc[j] / mass) * eConvert; | 
| 357 | // position whole step | 
| 358 | pos[j] += dt * vel[j]; | 
| 359 | } | 
| 360 |  | 
| 361 | integrableObjects[i]->setVel(vel); | 
| 362 | integrableObjects[i]->setPos(pos); | 
| 363 |  | 
| 364 | if (integrableObjects[i]->isDirectional()){ | 
| 365 |  | 
| 366 | // get and convert the torque to body frame | 
| 367 |  | 
| 368 | integrableObjects[i]->getTrq(Tb); | 
| 369 | integrableObjects[i]->lab2Body(Tb); | 
| 370 |  | 
| 371 | // get the angular momentum, and propagate a half step | 
| 372 |  | 
| 373 | integrableObjects[i]->getJ(ji); | 
| 374 |  | 
| 375 | for (j = 0; j < 3; j++) | 
| 376 | ji[j] += (dt2 * Tb[j]) * eConvert; | 
| 377 |  | 
| 378 | this->rotationPropagation( integrableObjects[i], ji ); | 
| 379 |  | 
| 380 | integrableObjects[i]->setJ(ji); | 
| 381 | } | 
| 382 | } | 
| 383 |  | 
| 384 | if (nConstrained){ | 
| 385 | constrainA(); | 
| 386 | } | 
| 387 | } | 
| 388 |  | 
| 389 |  | 
| 390 | template<typename T> void Integrator<T>::moveB(void){ | 
| 391 | int i, j; | 
| 392 | double Tb[3], ji[3]; | 
| 393 | double vel[3], frc[3]; | 
| 394 | double mass; | 
| 395 |  | 
| 396 | for (i = 0; i < integrableObjects.size(); i++){ | 
| 397 | integrableObjects[i]->getVel(vel); | 
| 398 | integrableObjects[i]->getFrc(frc); | 
| 399 |  | 
| 400 | mass = integrableObjects[i]->getMass(); | 
| 401 |  | 
| 402 | // velocity half step | 
| 403 | for (j = 0; j < 3; j++) | 
| 404 | vel[j] += (dt2 * frc[j] / mass) * eConvert; | 
| 405 |  | 
| 406 | integrableObjects[i]->setVel(vel); | 
| 407 |  | 
| 408 | if (integrableObjects[i]->isDirectional()){ | 
| 409 |  | 
| 410 | // get and convert the torque to body frame | 
| 411 |  | 
| 412 | integrableObjects[i]->getTrq(Tb); | 
| 413 | integrableObjects[i]->lab2Body(Tb); | 
| 414 |  | 
| 415 | // get the angular momentum, and propagate a half step | 
| 416 |  | 
| 417 | integrableObjects[i]->getJ(ji); | 
| 418 |  | 
| 419 | for (j = 0; j < 3; j++) | 
| 420 | ji[j] += (dt2 * Tb[j]) * eConvert; | 
| 421 |  | 
| 422 |  | 
| 423 | integrableObjects[i]->setJ(ji); | 
| 424 | } | 
| 425 | } | 
| 426 |  | 
| 427 | if (nConstrained){ | 
| 428 | constrainB(); | 
| 429 | } | 
| 430 | } | 
| 431 |  | 
| 432 | template<typename T> void Integrator<T>::preMove(void){ | 
| 433 | int i, j; | 
| 434 | double pos[3]; | 
| 435 |  | 
| 436 | if (nConstrained){ | 
| 437 | for (i = 0; i < nAtoms; i++){ | 
| 438 | atoms[i]->getPos(pos); | 
| 439 |  | 
| 440 | for (j = 0; j < 3; j++){ | 
| 441 | oldPos[3 * i + j] = pos[j]; | 
| 442 | } | 
| 443 | } | 
| 444 | } | 
| 445 | } | 
| 446 |  | 
| 447 | template<typename T> void Integrator<T>::constrainA(){ | 
| 448 | int i, j; | 
| 449 | int done; | 
| 450 | double posA[3], posB[3]; | 
| 451 | double velA[3], velB[3]; | 
| 452 | double pab[3]; | 
| 453 | double rab[3]; | 
| 454 | int a, b, ax, ay, az, bx, by, bz; | 
| 455 | double rma, rmb; | 
| 456 | double dx, dy, dz; | 
| 457 | double rpab; | 
| 458 | double rabsq, pabsq, rpabsq; | 
| 459 | double diffsq; | 
| 460 | double gab; | 
| 461 | int iteration; | 
| 462 |  | 
| 463 | for (i = 0; i < nAtoms; i++){ | 
| 464 | moving[i] = 0; | 
| 465 | moved[i] = 1; | 
| 466 | } | 
| 467 |  | 
| 468 | iteration = 0; | 
| 469 | done = 0; | 
| 470 | while (!done && (iteration < maxIteration)){ | 
| 471 | done = 1; | 
| 472 | for (i = 0; i < nConstrained; i++){ | 
| 473 | a = constrainedA[i]; | 
| 474 | b = constrainedB[i]; | 
| 475 |  | 
| 476 | ax = (a * 3) + 0; | 
| 477 | ay = (a * 3) + 1; | 
| 478 | az = (a * 3) + 2; | 
| 479 |  | 
| 480 | bx = (b * 3) + 0; | 
| 481 | by = (b * 3) + 1; | 
| 482 | bz = (b * 3) + 2; | 
| 483 |  | 
| 484 | if (moved[a] || moved[b]){ | 
| 485 | atoms[a]->getPos(posA); | 
| 486 | atoms[b]->getPos(posB); | 
| 487 |  | 
| 488 | for (j = 0; j < 3; j++) | 
| 489 | pab[j] = posA[j] - posB[j]; | 
| 490 |  | 
| 491 | //periodic boundary condition | 
| 492 |  | 
| 493 | info->wrapVector(pab); | 
| 494 |  | 
| 495 | pabsq = pab[0] * pab[0] + pab[1] * pab[1] + pab[2] * pab[2]; | 
| 496 |  | 
| 497 | rabsq = constrainedDsqr[i]; | 
| 498 | diffsq = rabsq - pabsq; | 
| 499 |  | 
| 500 | // the original rattle code from alan tidesley | 
| 501 | if (fabs(diffsq) > (tol * rabsq * 2)){ | 
| 502 | rab[0] = oldPos[ax] - oldPos[bx]; | 
| 503 | rab[1] = oldPos[ay] - oldPos[by]; | 
| 504 | rab[2] = oldPos[az] - oldPos[bz]; | 
| 505 |  | 
| 506 | info->wrapVector(rab); | 
| 507 |  | 
| 508 | rpab = rab[0] * pab[0] + rab[1] * pab[1] + rab[2] * pab[2]; | 
| 509 |  | 
| 510 | rpabsq = rpab * rpab; | 
| 511 |  | 
| 512 |  | 
| 513 | if (rpabsq < (rabsq * -diffsq)){ | 
| 514 | #ifdef IS_MPI | 
| 515 | a = atoms[a]->getGlobalIndex(); | 
| 516 | b = atoms[b]->getGlobalIndex(); | 
| 517 | #endif //is_mpi | 
| 518 | sprintf(painCave.errMsg, | 
| 519 | "Constraint failure in constrainA at atom %d and %d.\n", a, | 
| 520 | b); | 
| 521 | painCave.isFatal = 1; | 
| 522 | simError(); | 
| 523 | } | 
| 524 |  | 
| 525 | rma = 1.0 / atoms[a]->getMass(); | 
| 526 | rmb = 1.0 / atoms[b]->getMass(); | 
| 527 |  | 
| 528 | gab = diffsq / (2.0 * (rma + rmb) * rpab); | 
| 529 |  | 
| 530 | dx = rab[0] * gab; | 
| 531 | dy = rab[1] * gab; | 
| 532 | dz = rab[2] * gab; | 
| 533 |  | 
| 534 | posA[0] += rma * dx; | 
| 535 | posA[1] += rma * dy; | 
| 536 | posA[2] += rma * dz; | 
| 537 |  | 
| 538 | atoms[a]->setPos(posA); | 
| 539 |  | 
| 540 | posB[0] -= rmb * dx; | 
| 541 | posB[1] -= rmb * dy; | 
| 542 | posB[2] -= rmb * dz; | 
| 543 |  | 
| 544 | atoms[b]->setPos(posB); | 
| 545 |  | 
| 546 | dx = dx / dt; | 
| 547 | dy = dy / dt; | 
| 548 | dz = dz / dt; | 
| 549 |  | 
| 550 | atoms[a]->getVel(velA); | 
| 551 |  | 
| 552 | velA[0] += rma * dx; | 
| 553 | velA[1] += rma * dy; | 
| 554 | velA[2] += rma * dz; | 
| 555 |  | 
| 556 | atoms[a]->setVel(velA); | 
| 557 |  | 
| 558 | atoms[b]->getVel(velB); | 
| 559 |  | 
| 560 | velB[0] -= rmb * dx; | 
| 561 | velB[1] -= rmb * dy; | 
| 562 | velB[2] -= rmb * dz; | 
| 563 |  | 
| 564 | atoms[b]->setVel(velB); | 
| 565 |  | 
| 566 | moving[a] = 1; | 
| 567 | moving[b] = 1; | 
| 568 | done = 0; | 
| 569 | } | 
| 570 | } | 
| 571 | } | 
| 572 |  | 
| 573 | for (i = 0; i < nAtoms; i++){ | 
| 574 | moved[i] = moving[i]; | 
| 575 | moving[i] = 0; | 
| 576 | } | 
| 577 |  | 
| 578 | iteration++; | 
| 579 | } | 
| 580 |  | 
| 581 | if (!done){ | 
| 582 | sprintf(painCave.errMsg, | 
| 583 | "Constraint failure in constrainA, too many iterations: %d\n", | 
| 584 | iteration); | 
| 585 | painCave.isFatal = 1; | 
| 586 | simError(); | 
| 587 | } | 
| 588 |  | 
| 589 | } | 
| 590 |  | 
| 591 | template<typename T> void Integrator<T>::constrainB(void){ | 
| 592 | int i, j; | 
| 593 | int done; | 
| 594 | double posA[3], posB[3]; | 
| 595 | double velA[3], velB[3]; | 
| 596 | double vxab, vyab, vzab; | 
| 597 | double rab[3]; | 
| 598 | int a, b, ax, ay, az, bx, by, bz; | 
| 599 | double rma, rmb; | 
| 600 | double dx, dy, dz; | 
| 601 | double rvab; | 
| 602 | double gab; | 
| 603 | int iteration; | 
| 604 |  | 
| 605 | for (i = 0; i < nAtoms; i++){ | 
| 606 | moving[i] = 0; | 
| 607 | moved[i] = 1; | 
| 608 | } | 
| 609 |  | 
| 610 | done = 0; | 
| 611 | iteration = 0; | 
| 612 | while (!done && (iteration < maxIteration)){ | 
| 613 | done = 1; | 
| 614 |  | 
| 615 | for (i = 0; i < nConstrained; i++){ | 
| 616 | a = constrainedA[i]; | 
| 617 | b = constrainedB[i]; | 
| 618 |  | 
| 619 | ax = (a * 3) + 0; | 
| 620 | ay = (a * 3) + 1; | 
| 621 | az = (a * 3) + 2; | 
| 622 |  | 
| 623 | bx = (b * 3) + 0; | 
| 624 | by = (b * 3) + 1; | 
| 625 | bz = (b * 3) + 2; | 
| 626 |  | 
| 627 | if (moved[a] || moved[b]){ | 
| 628 | atoms[a]->getVel(velA); | 
| 629 | atoms[b]->getVel(velB); | 
| 630 |  | 
| 631 | vxab = velA[0] - velB[0]; | 
| 632 | vyab = velA[1] - velB[1]; | 
| 633 | vzab = velA[2] - velB[2]; | 
| 634 |  | 
| 635 | atoms[a]->getPos(posA); | 
| 636 | atoms[b]->getPos(posB); | 
| 637 |  | 
| 638 | for (j = 0; j < 3; j++) | 
| 639 | rab[j] = posA[j] - posB[j]; | 
| 640 |  | 
| 641 | info->wrapVector(rab); | 
| 642 |  | 
| 643 | rma = 1.0 / atoms[a]->getMass(); | 
| 644 | rmb = 1.0 / atoms[b]->getMass(); | 
| 645 |  | 
| 646 | rvab = rab[0] * vxab + rab[1] * vyab + rab[2] * vzab; | 
| 647 |  | 
| 648 | gab = -rvab / ((rma + rmb) * constrainedDsqr[i]); | 
| 649 |  | 
| 650 | if (fabs(gab) > tol){ | 
| 651 | dx = rab[0] * gab; | 
| 652 | dy = rab[1] * gab; | 
| 653 | dz = rab[2] * gab; | 
| 654 |  | 
| 655 | velA[0] += rma * dx; | 
| 656 | velA[1] += rma * dy; | 
| 657 | velA[2] += rma * dz; | 
| 658 |  | 
| 659 | atoms[a]->setVel(velA); | 
| 660 |  | 
| 661 | velB[0] -= rmb * dx; | 
| 662 | velB[1] -= rmb * dy; | 
| 663 | velB[2] -= rmb * dz; | 
| 664 |  | 
| 665 | atoms[b]->setVel(velB); | 
| 666 |  | 
| 667 | moving[a] = 1; | 
| 668 | moving[b] = 1; | 
| 669 | done = 0; | 
| 670 | } | 
| 671 | } | 
| 672 | } | 
| 673 |  | 
| 674 | for (i = 0; i < nAtoms; i++){ | 
| 675 | moved[i] = moving[i]; | 
| 676 | moving[i] = 0; | 
| 677 | } | 
| 678 |  | 
| 679 | iteration++; | 
| 680 | } | 
| 681 |  | 
| 682 | if (!done){ | 
| 683 | sprintf(painCave.errMsg, | 
| 684 | "Constraint failure in constrainB, too many iterations: %d\n", | 
| 685 | iteration); | 
| 686 | painCave.isFatal = 1; | 
| 687 | simError(); | 
| 688 | } | 
| 689 | } | 
| 690 |  | 
| 691 | template<typename T> void Integrator<T>::rotationPropagation | 
| 692 | ( StuntDouble* sd, double ji[3] ){ | 
| 693 |  | 
| 694 | double angle; | 
| 695 | double A[3][3], I[3][3]; | 
| 696 | int i, j, k; | 
| 697 |  | 
| 698 | // use the angular velocities to propagate the rotation matrix a | 
| 699 | // full time step | 
| 700 |  | 
| 701 | sd->getA(A); | 
| 702 | sd->getI(I); | 
| 703 |  | 
| 704 | if (sd->isLinear()) { | 
| 705 | i = sd->linearAxis(); | 
| 706 | j = (i+1)%3; | 
| 707 | k = (i+2)%3; | 
| 708 |  | 
| 709 | angle = dt2 * ji[j] / I[j][j]; | 
| 710 | this->rotate( k, i, angle, ji, A ); | 
| 711 |  | 
| 712 | angle = dt * ji[k] / I[k][k]; | 
| 713 | this->rotate( i, j, angle, ji, A); | 
| 714 |  | 
| 715 | angle = dt2 * ji[j] / I[j][j]; | 
| 716 | this->rotate( k, i, angle, ji, A ); | 
| 717 |  | 
| 718 | } else { | 
| 719 | // rotate about the x-axis | 
| 720 | angle = dt2 * ji[0] / I[0][0]; | 
| 721 | this->rotate( 1, 2, angle, ji, A ); | 
| 722 |  | 
| 723 | // rotate about the y-axis | 
| 724 | angle = dt2 * ji[1] / I[1][1]; | 
| 725 | this->rotate( 2, 0, angle, ji, A ); | 
| 726 |  | 
| 727 | // rotate about the z-axis | 
| 728 | angle = dt * ji[2] / I[2][2]; | 
| 729 | this->rotate( 0, 1, angle, ji, A); | 
| 730 |  | 
| 731 | // rotate about the y-axis | 
| 732 | angle = dt2 * ji[1] / I[1][1]; | 
| 733 | this->rotate( 2, 0, angle, ji, A ); | 
| 734 |  | 
| 735 | // rotate about the x-axis | 
| 736 | angle = dt2 * ji[0] / I[0][0]; | 
| 737 | this->rotate( 1, 2, angle, ji, A ); | 
| 738 |  | 
| 739 | } | 
| 740 | sd->setA( A  ); | 
| 741 | } | 
| 742 |  | 
| 743 | template<typename T> void Integrator<T>::rotate(int axes1, int axes2, | 
| 744 | double angle, double ji[3], | 
| 745 | double A[3][3]){ | 
| 746 | int i, j, k; | 
| 747 | double sinAngle; | 
| 748 | double cosAngle; | 
| 749 | double angleSqr; | 
| 750 | double angleSqrOver4; | 
| 751 | double top, bottom; | 
| 752 | double rot[3][3]; | 
| 753 | double tempA[3][3]; | 
| 754 | double tempJ[3]; | 
| 755 |  | 
| 756 | // initialize the tempA | 
| 757 |  | 
| 758 | for (i = 0; i < 3; i++){ | 
| 759 | for (j = 0; j < 3; j++){ | 
| 760 | tempA[j][i] = A[i][j]; | 
| 761 | } | 
| 762 | } | 
| 763 |  | 
| 764 | // initialize the tempJ | 
| 765 |  | 
| 766 | for (i = 0; i < 3; i++) | 
| 767 | tempJ[i] = ji[i]; | 
| 768 |  | 
| 769 | // initalize rot as a unit matrix | 
| 770 |  | 
| 771 | rot[0][0] = 1.0; | 
| 772 | rot[0][1] = 0.0; | 
| 773 | rot[0][2] = 0.0; | 
| 774 |  | 
| 775 | rot[1][0] = 0.0; | 
| 776 | rot[1][1] = 1.0; | 
| 777 | rot[1][2] = 0.0; | 
| 778 |  | 
| 779 | rot[2][0] = 0.0; | 
| 780 | rot[2][1] = 0.0; | 
| 781 | rot[2][2] = 1.0; | 
| 782 |  | 
| 783 | // use a small angle aproximation for sin and cosine | 
| 784 |  | 
| 785 | angleSqr = angle * angle; | 
| 786 | angleSqrOver4 = angleSqr / 4.0; | 
| 787 | top = 1.0 - angleSqrOver4; | 
| 788 | bottom = 1.0 + angleSqrOver4; | 
| 789 |  | 
| 790 | cosAngle = top / bottom; | 
| 791 | sinAngle = angle / bottom; | 
| 792 |  | 
| 793 | rot[axes1][axes1] = cosAngle; | 
| 794 | rot[axes2][axes2] = cosAngle; | 
| 795 |  | 
| 796 | rot[axes1][axes2] = sinAngle; | 
| 797 | rot[axes2][axes1] = -sinAngle; | 
| 798 |  | 
| 799 | // rotate the momentum acoording to: ji[] = rot[][] * ji[] | 
| 800 |  | 
| 801 | for (i = 0; i < 3; i++){ | 
| 802 | ji[i] = 0.0; | 
| 803 | for (k = 0; k < 3; k++){ | 
| 804 | ji[i] += rot[i][k] * tempJ[k]; | 
| 805 | } | 
| 806 | } | 
| 807 |  | 
| 808 | // rotate the Rotation matrix acording to: | 
| 809 | //            A[][] = A[][] * transpose(rot[][]) | 
| 810 |  | 
| 811 |  | 
| 812 | // NOte for as yet unknown reason, we are performing the | 
| 813 | // calculation as: | 
| 814 | //                transpose(A[][]) = transpose(A[][]) * transpose(rot[][]) | 
| 815 |  | 
| 816 | for (i = 0; i < 3; i++){ | 
| 817 | for (j = 0; j < 3; j++){ | 
| 818 | A[j][i] = 0.0; | 
| 819 | for (k = 0; k < 3; k++){ | 
| 820 | A[j][i] += tempA[i][k] * rot[j][k]; | 
| 821 | } | 
| 822 | } | 
| 823 | } | 
| 824 | } | 
| 825 |  | 
| 826 | template<typename T> void Integrator<T>::calcForce(int calcPot, int calcStress){ | 
| 827 | myFF->doForces(calcPot, calcStress); | 
| 828 | } | 
| 829 |  | 
| 830 | template<typename T> void Integrator<T>::thermalize(){ | 
| 831 | tStats->velocitize(); | 
| 832 | } | 
| 833 |  | 
| 834 | template<typename T> double Integrator<T>::getConservedQuantity(void){ | 
| 835 | return tStats->getTotalE(); | 
| 836 | } | 
| 837 | template<typename T> string Integrator<T>::getAdditionalParameters(void){ | 
| 838 | //By default, return a null string | 
| 839 | //The reason we use string instead of char* is that if we use char*, we will | 
| 840 | //return a pointer point to local variable which might cause problem | 
| 841 | return string(); | 
| 842 | } |