| 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 | #include "Integrator.hpp" | 
| 11 | #include "simError.h" | 
| 12 |  | 
| 13 |  | 
| 14 | template<typename T> Integrator<T>::Integrator(SimInfo* theInfo, | 
| 15 | ForceFields* the_ff){ | 
| 16 | 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 |  | 
| 25 | if (info->the_integrator != NULL){ | 
| 26 | delete info->the_integrator; | 
| 27 | } | 
| 28 |  | 
| 29 | nAtoms = info->n_atoms; | 
| 30 |  | 
| 31 | // check for constraints | 
| 32 |  | 
| 33 | constrainedA = NULL; | 
| 34 | constrainedB = NULL; | 
| 35 | constrainedDsqr = NULL; | 
| 36 | moving = NULL; | 
| 37 | moved = NULL; | 
| 38 | oldPos = NULL; | 
| 39 |  | 
| 40 | nConstrained = 0; | 
| 41 |  | 
| 42 | checkConstraints(); | 
| 43 | } | 
| 44 |  | 
| 45 | template<typename T> Integrator<T>::~Integrator(){ | 
| 46 | if (nConstrained){ | 
| 47 | delete[] constrainedA; | 
| 48 | delete[] constrainedB; | 
| 49 | delete[] constrainedDsqr; | 
| 50 | delete[] moving; | 
| 51 | delete[] moved; | 
| 52 | delete[] oldPos; | 
| 53 | } | 
| 54 | } | 
| 55 |  | 
| 56 | template<typename T> void Integrator<T>::checkConstraints(void){ | 
| 57 | isConstrained = 0; | 
| 58 |  | 
| 59 | Constraint* temp_con; | 
| 60 | Constraint* dummy_plug; | 
| 61 | temp_con = new Constraint[info->n_SRI]; | 
| 62 | nConstrained = 0; | 
| 63 | int constrained = 0; | 
| 64 |  | 
| 65 | SRI** theArray; | 
| 66 | for (int i = 0; i < nMols; i++){ | 
| 67 | theArray = (SRI * *) molecules[i].getMyBonds(); | 
| 68 | for (int j = 0; j < molecules[i].getNBonds(); j++){ | 
| 69 | constrained = theArray[j]->is_constrained(); | 
| 70 |  | 
| 71 | 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 |  | 
| 77 | nConstrained++; | 
| 78 | constrained = 0; | 
| 79 | } | 
| 80 | } | 
| 81 |  | 
| 82 | theArray = (SRI * *) molecules[i].getMyBends(); | 
| 83 | for (int j = 0; j < molecules[i].getNBends(); j++){ | 
| 84 | constrained = theArray[j]->is_constrained(); | 
| 85 |  | 
| 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 | } | 
| 95 | } | 
| 96 |  | 
| 97 | theArray = (SRI * *) molecules[i].getMyTorsions(); | 
| 98 | for (int j = 0; j < molecules[i].getNTorsions(); j++){ | 
| 99 | constrained = theArray[j]->is_constrained(); | 
| 100 |  | 
| 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 | } | 
| 110 | } | 
| 111 | } | 
| 112 |  | 
| 113 | if (nConstrained > 0){ | 
| 114 | isConstrained = 1; | 
| 115 |  | 
| 116 | if (constrainedA != NULL) | 
| 117 | delete[] constrainedA; | 
| 118 | if (constrainedB != NULL) | 
| 119 | delete[] constrainedB; | 
| 120 | if (constrainedDsqr != NULL) | 
| 121 | delete[] constrainedDsqr; | 
| 122 |  | 
| 123 | constrainedA = new int[nConstrained]; | 
| 124 | constrainedB = new int[nConstrained]; | 
| 125 | constrainedDsqr = new double[nConstrained]; | 
| 126 |  | 
| 127 | for (int i = 0; i < nConstrained; i++){ | 
| 128 | 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 |  | 
| 134 | // save oldAtoms to check for lode balanceing later on. | 
| 135 |  | 
| 136 | oldAtoms = nAtoms; | 
| 137 |  | 
| 138 | moving = new int[nAtoms]; | 
| 139 | moved = new int[nAtoms]; | 
| 140 |  | 
| 141 | oldPos = new double[nAtoms * 3]; | 
| 142 | } | 
| 143 |  | 
| 144 | delete[] temp_con; | 
| 145 | } | 
| 146 |  | 
| 147 |  | 
| 148 | template<typename T> void Integrator<T>::integrate(void){ | 
| 149 |  | 
| 150 | double runTime = info->run_time; | 
| 151 | double sampleTime = info->sampleTime; | 
| 152 | double statusTime = info->statusTime; | 
| 153 | double thermalTime = info->thermalTime; | 
| 154 | double resetTime = info->resetTime; | 
| 155 |  | 
| 156 |  | 
| 157 | double currSample; | 
| 158 | double currThermal; | 
| 159 | double currStatus; | 
| 160 | double currReset; | 
| 161 |  | 
| 162 | int calcPot, calcStress; | 
| 163 |  | 
| 164 | tStats = new Thermo(info); | 
| 165 | statOut = new StatWriter(info); | 
| 166 | dumpOut = new DumpWriter(info); | 
| 167 |  | 
| 168 | atoms = info->atoms; | 
| 169 |  | 
| 170 | dt = info->dt; | 
| 171 | dt2 = 0.5 * dt; | 
| 172 |  | 
| 173 | readyCheck(); | 
| 174 |  | 
| 175 | // initialize the forces before the first step | 
| 176 |  | 
| 177 | calcForce(1, 1); | 
| 178 |  | 
| 179 | if (nConstrained){ | 
| 180 | preMove(); | 
| 181 | constrainA(); | 
| 182 | calcForce(1, 1); | 
| 183 | constrainB(); | 
| 184 | } | 
| 185 |  | 
| 186 | if (info->setTemp){ | 
| 187 | thermalize(); | 
| 188 | } | 
| 189 |  | 
| 190 | calcPot     = 0; | 
| 191 | calcStress  = 0; | 
| 192 | currSample  = sampleTime + info->getTime(); | 
| 193 | currThermal = thermalTime+ info->getTime(); | 
| 194 | currStatus  = statusTime + info->getTime(); | 
| 195 | currReset   = resetTime  + info->getTime(); | 
| 196 |  | 
| 197 | dumpOut->writeDump(info->getTime()); | 
| 198 | statOut->writeStat(info->getTime()); | 
| 199 |  | 
| 200 |  | 
| 201 |  | 
| 202 | #ifdef IS_MPI | 
| 203 | strcpy(checkPointMsg, "The integrator is ready to go."); | 
| 204 | MPIcheckPoint(); | 
| 205 | #endif // is_mpi | 
| 206 |  | 
| 207 | while (info->getTime() < runTime){ | 
| 208 | if ((info->getTime() + dt) >= currStatus){ | 
| 209 | calcPot = 1; | 
| 210 | calcStress = 1; | 
| 211 | } | 
| 212 |  | 
| 213 | integrateStep(calcPot, calcStress); | 
| 214 |  | 
| 215 | info->incrTime(dt); | 
| 216 |  | 
| 217 | if (info->setTemp){ | 
| 218 | if (info->getTime() >= currThermal){ | 
| 219 | thermalize(); | 
| 220 | currThermal += thermalTime; | 
| 221 | } | 
| 222 | } | 
| 223 |  | 
| 224 | if (info->getTime() >= currSample){ | 
| 225 | dumpOut->writeDump(info->getTime()); | 
| 226 | currSample += sampleTime; | 
| 227 | } | 
| 228 |  | 
| 229 | if (info->getTime() >= currStatus){ | 
| 230 | statOut->writeStat(info->getTime()); | 
| 231 | calcPot = 0; | 
| 232 | calcStress = 0; | 
| 233 | currStatus += statusTime; | 
| 234 | } | 
| 235 |  | 
| 236 | if (info->resetIntegrator){ | 
| 237 | if (info->getTime() >= currReset){ | 
| 238 | this->resetIntegrator(); | 
| 239 | currReset += resetTime; | 
| 240 | } | 
| 241 | } | 
| 242 |  | 
| 243 | #ifdef IS_MPI | 
| 244 | strcpy(checkPointMsg, "successfully took a time step."); | 
| 245 | MPIcheckPoint(); | 
| 246 | #endif // is_mpi | 
| 247 | } | 
| 248 |  | 
| 249 |  | 
| 250 | // write the last frame | 
| 251 | dumpOut->writeDump(info->getTime()); | 
| 252 |  | 
| 253 | delete dumpOut; | 
| 254 | delete statOut; | 
| 255 | } | 
| 256 |  | 
| 257 | template<typename T> void Integrator<T>::integrateStep(int calcPot, | 
| 258 | int calcStress){ | 
| 259 | // Position full step, and velocity half step | 
| 260 | preMove(); | 
| 261 |  | 
| 262 | moveA(); | 
| 263 |  | 
| 264 |  | 
| 265 |  | 
| 266 |  | 
| 267 | #ifdef IS_MPI | 
| 268 | strcpy(checkPointMsg, "Succesful moveA\n"); | 
| 269 | MPIcheckPoint(); | 
| 270 | #endif // is_mpi | 
| 271 |  | 
| 272 |  | 
| 273 | // calc forces | 
| 274 |  | 
| 275 | calcForce(calcPot, calcStress); | 
| 276 |  | 
| 277 | #ifdef IS_MPI | 
| 278 | strcpy(checkPointMsg, "Succesful doForces\n"); | 
| 279 | MPIcheckPoint(); | 
| 280 | #endif // is_mpi | 
| 281 |  | 
| 282 |  | 
| 283 | // finish the velocity  half step | 
| 284 |  | 
| 285 | moveB(); | 
| 286 |  | 
| 287 |  | 
| 288 |  | 
| 289 | #ifdef IS_MPI | 
| 290 | strcpy(checkPointMsg, "Succesful moveB\n"); | 
| 291 | MPIcheckPoint(); | 
| 292 | #endif // is_mpi | 
| 293 | } | 
| 294 |  | 
| 295 |  | 
| 296 | template<typename T> void Integrator<T>::moveA(void){ | 
| 297 | int i, j; | 
| 298 | DirectionalAtom* dAtom; | 
| 299 | double Tb[3], ji[3]; | 
| 300 | double vel[3], pos[3], frc[3]; | 
| 301 | double mass; | 
| 302 |  | 
| 303 | for (i = 0; i < nAtoms; i++){ | 
| 304 | atoms[i]->getVel(vel); | 
| 305 | atoms[i]->getPos(pos); | 
| 306 | atoms[i]->getFrc(frc); | 
| 307 |  | 
| 308 | mass = atoms[i]->getMass(); | 
| 309 |  | 
| 310 | for (j = 0; j < 3; j++){ | 
| 311 | // velocity half step | 
| 312 | vel[j] += (dt2 * frc[j] / mass) * eConvert; | 
| 313 | // position whole step | 
| 314 | pos[j] += dt * vel[j]; | 
| 315 | } | 
| 316 |  | 
| 317 | atoms[i]->setVel(vel); | 
| 318 | atoms[i]->setPos(pos); | 
| 319 |  | 
| 320 | if (atoms[i]->isDirectional()){ | 
| 321 | dAtom = (DirectionalAtom *) atoms[i]; | 
| 322 |  | 
| 323 | // get and convert the torque to body frame | 
| 324 |  | 
| 325 | dAtom->getTrq(Tb); | 
| 326 | dAtom->lab2Body(Tb); | 
| 327 |  | 
| 328 | // get the angular momentum, and propagate a half step | 
| 329 |  | 
| 330 | dAtom->getJ(ji); | 
| 331 |  | 
| 332 | for (j = 0; j < 3; j++) | 
| 333 | ji[j] += (dt2 * Tb[j]) * eConvert; | 
| 334 |  | 
| 335 | this->rotationPropagation( dAtom, ji ); | 
| 336 |  | 
| 337 | dAtom->setJ(ji); | 
| 338 | } | 
| 339 | } | 
| 340 |  | 
| 341 | if (nConstrained){ | 
| 342 | constrainA(); | 
| 343 | } | 
| 344 | } | 
| 345 |  | 
| 346 |  | 
| 347 | template<typename T> void Integrator<T>::moveB(void){ | 
| 348 | int i, j; | 
| 349 | DirectionalAtom* dAtom; | 
| 350 | double Tb[3], ji[3]; | 
| 351 | double vel[3], frc[3]; | 
| 352 | double mass; | 
| 353 |  | 
| 354 | for (i = 0; i < nAtoms; i++){ | 
| 355 | atoms[i]->getVel(vel); | 
| 356 | atoms[i]->getFrc(frc); | 
| 357 |  | 
| 358 | mass = atoms[i]->getMass(); | 
| 359 |  | 
| 360 | // velocity half step | 
| 361 | for (j = 0; j < 3; j++) | 
| 362 | vel[j] += (dt2 * frc[j] / mass) * eConvert; | 
| 363 |  | 
| 364 | atoms[i]->setVel(vel); | 
| 365 |  | 
| 366 | if (atoms[i]->isDirectional()){ | 
| 367 | dAtom = (DirectionalAtom *) atoms[i]; | 
| 368 |  | 
| 369 | // get and convert the torque to body frame | 
| 370 |  | 
| 371 | dAtom->getTrq(Tb); | 
| 372 | dAtom->lab2Body(Tb); | 
| 373 |  | 
| 374 | // get the angular momentum, and propagate a half step | 
| 375 |  | 
| 376 | dAtom->getJ(ji); | 
| 377 |  | 
| 378 | for (j = 0; j < 3; j++) | 
| 379 | ji[j] += (dt2 * Tb[j]) * eConvert; | 
| 380 |  | 
| 381 |  | 
| 382 | dAtom->setJ(ji); | 
| 383 | } | 
| 384 | } | 
| 385 |  | 
| 386 | if (nConstrained){ | 
| 387 | constrainB(); | 
| 388 | } | 
| 389 | } | 
| 390 |  | 
| 391 | template<typename T> void Integrator<T>::preMove(void){ | 
| 392 | int i, j; | 
| 393 | double pos[3]; | 
| 394 |  | 
| 395 | if (nConstrained){ | 
| 396 | for (i = 0; i < nAtoms; i++){ | 
| 397 | atoms[i]->getPos(pos); | 
| 398 |  | 
| 399 | for (j = 0; j < 3; j++){ | 
| 400 | oldPos[3 * i + j] = pos[j]; | 
| 401 | } | 
| 402 | } | 
| 403 | } | 
| 404 | } | 
| 405 |  | 
| 406 | template<typename T> void Integrator<T>::constrainA(){ | 
| 407 | int i, j; | 
| 408 | int done; | 
| 409 | double posA[3], posB[3]; | 
| 410 | double velA[3], velB[3]; | 
| 411 | double pab[3]; | 
| 412 | double rab[3]; | 
| 413 | int a, b, ax, ay, az, bx, by, bz; | 
| 414 | double rma, rmb; | 
| 415 | double dx, dy, dz; | 
| 416 | double rpab; | 
| 417 | double rabsq, pabsq, rpabsq; | 
| 418 | double diffsq; | 
| 419 | double gab; | 
| 420 | int iteration; | 
| 421 |  | 
| 422 | for (i = 0; i < nAtoms; i++){ | 
| 423 | moving[i] = 0; | 
| 424 | moved[i] = 1; | 
| 425 | } | 
| 426 |  | 
| 427 | iteration = 0; | 
| 428 | done = 0; | 
| 429 | while (!done && (iteration < maxIteration)){ | 
| 430 | done = 1; | 
| 431 | for (i = 0; i < nConstrained; i++){ | 
| 432 | a = constrainedA[i]; | 
| 433 | b = constrainedB[i]; | 
| 434 |  | 
| 435 | ax = (a * 3) + 0; | 
| 436 | ay = (a * 3) + 1; | 
| 437 | az = (a * 3) + 2; | 
| 438 |  | 
| 439 | 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 | pab[j] = posA[j] - posB[j]; | 
| 449 |  | 
| 450 | //periodic boundary condition | 
| 451 |  | 
| 452 | info->wrapVector(pab); | 
| 453 |  | 
| 454 | pabsq = pab[0] * pab[0] + pab[1] * pab[1] + pab[2] * pab[2]; | 
| 455 |  | 
| 456 | rabsq = constrainedDsqr[i]; | 
| 457 | diffsq = rabsq - pabsq; | 
| 458 |  | 
| 459 | // 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 |  | 
| 465 | info->wrapVector(rab); | 
| 466 |  | 
| 467 | rpab = rab[0] * pab[0] + rab[1] * pab[1] + rab[2] * pab[2]; | 
| 468 |  | 
| 469 | rpabsq = rpab * rpab; | 
| 470 |  | 
| 471 |  | 
| 472 | if (rpabsq < (rabsq * -diffsq)){ | 
| 473 | #ifdef IS_MPI | 
| 474 | a = atoms[a]->getGlobalIndex(); | 
| 475 | b = atoms[b]->getGlobalIndex(); | 
| 476 | #endif //is_mpi | 
| 477 | 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 |  | 
| 484 | rma = 1.0 / atoms[a]->getMass(); | 
| 485 | rmb = 1.0 / atoms[b]->getMass(); | 
| 486 |  | 
| 487 | gab = diffsq / (2.0 * (rma + rmb) * rpab); | 
| 488 |  | 
| 489 | dx = rab[0] * gab; | 
| 490 | dy = rab[1] * gab; | 
| 491 | dz = rab[2] * gab; | 
| 492 |  | 
| 493 | posA[0] += rma * dx; | 
| 494 | posA[1] += rma * dy; | 
| 495 | posA[2] += rma * dz; | 
| 496 |  | 
| 497 | atoms[a]->setPos(posA); | 
| 498 |  | 
| 499 | posB[0] -= rmb * dx; | 
| 500 | posB[1] -= rmb * dy; | 
| 501 | posB[2] -= rmb * dz; | 
| 502 |  | 
| 503 | atoms[b]->setPos(posB); | 
| 504 |  | 
| 505 | dx = dx / dt; | 
| 506 | dy = dy / dt; | 
| 507 | dz = dz / dt; | 
| 508 |  | 
| 509 | atoms[a]->getVel(velA); | 
| 510 |  | 
| 511 | velA[0] += rma * dx; | 
| 512 | velA[1] += rma * dy; | 
| 513 | velA[2] += rma * dz; | 
| 514 |  | 
| 515 | atoms[a]->setVel(velA); | 
| 516 |  | 
| 517 | atoms[b]->getVel(velB); | 
| 518 |  | 
| 519 | velB[0] -= rmb * dx; | 
| 520 | velB[1] -= rmb * dy; | 
| 521 | velB[2] -= rmb * dz; | 
| 522 |  | 
| 523 | atoms[b]->setVel(velB); | 
| 524 |  | 
| 525 | moving[a] = 1; | 
| 526 | moving[b] = 1; | 
| 527 | done = 0; | 
| 528 | } | 
| 529 | } | 
| 530 | } | 
| 531 |  | 
| 532 | for (i = 0; i < nAtoms; i++){ | 
| 533 | moved[i] = moving[i]; | 
| 534 | moving[i] = 0; | 
| 535 | } | 
| 536 |  | 
| 537 | iteration++; | 
| 538 | } | 
| 539 |  | 
| 540 | if (!done){ | 
| 541 | sprintf(painCave.errMsg, | 
| 542 | "Constraint failure in constrainA, too many iterations: %d\n", | 
| 543 | iteration); | 
| 544 | painCave.isFatal = 1; | 
| 545 | simError(); | 
| 546 | } | 
| 547 |  | 
| 548 | } | 
| 549 |  | 
| 550 | template<typename T> void Integrator<T>::constrainB(void){ | 
| 551 | int i, j; | 
| 552 | int done; | 
| 553 | double posA[3], posB[3]; | 
| 554 | double velA[3], velB[3]; | 
| 555 | double vxab, vyab, vzab; | 
| 556 | double rab[3]; | 
| 557 | int a, b, ax, ay, az, bx, by, bz; | 
| 558 | double rma, rmb; | 
| 559 | double dx, dy, dz; | 
| 560 | double rvab; | 
| 561 | double gab; | 
| 562 | int iteration; | 
| 563 |  | 
| 564 | for (i = 0; i < nAtoms; i++){ | 
| 565 | moving[i] = 0; | 
| 566 | moved[i] = 1; | 
| 567 | } | 
| 568 |  | 
| 569 | done = 0; | 
| 570 | iteration = 0; | 
| 571 | while (!done && (iteration < maxIteration)){ | 
| 572 | done = 1; | 
| 573 |  | 
| 574 | for (i = 0; i < nConstrained; i++){ | 
| 575 | a = constrainedA[i]; | 
| 576 | b = constrainedB[i]; | 
| 577 |  | 
| 578 | ax = (a * 3) + 0; | 
| 579 | ay = (a * 3) + 1; | 
| 580 | az = (a * 3) + 2; | 
| 581 |  | 
| 582 | bx = (b * 3) + 0; | 
| 583 | by = (b * 3) + 1; | 
| 584 | bz = (b * 3) + 2; | 
| 585 |  | 
| 586 | if (moved[a] || moved[b]){ | 
| 587 | atoms[a]->getVel(velA); | 
| 588 | atoms[b]->getVel(velB); | 
| 589 |  | 
| 590 | vxab = velA[0] - velB[0]; | 
| 591 | vyab = velA[1] - velB[1]; | 
| 592 | vzab = velA[2] - velB[2]; | 
| 593 |  | 
| 594 | atoms[a]->getPos(posA); | 
| 595 | atoms[b]->getPos(posB); | 
| 596 |  | 
| 597 | for (j = 0; j < 3; j++) | 
| 598 | rab[j] = posA[j] - posB[j]; | 
| 599 |  | 
| 600 | info->wrapVector(rab); | 
| 601 |  | 
| 602 | rma = 1.0 / atoms[a]->getMass(); | 
| 603 | rmb = 1.0 / atoms[b]->getMass(); | 
| 604 |  | 
| 605 | rvab = rab[0] * vxab + rab[1] * vyab + rab[2] * vzab; | 
| 606 |  | 
| 607 | gab = -rvab / ((rma + rmb) * constrainedDsqr[i]); | 
| 608 |  | 
| 609 | 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 | } | 
| 631 | } | 
| 632 |  | 
| 633 | for (i = 0; i < nAtoms; i++){ | 
| 634 | moved[i] = moving[i]; | 
| 635 | moving[i] = 0; | 
| 636 | } | 
| 637 |  | 
| 638 | iteration++; | 
| 639 | } | 
| 640 |  | 
| 641 | if (!done){ | 
| 642 | sprintf(painCave.errMsg, | 
| 643 | "Constraint failure in constrainB, too many iterations: %d\n", | 
| 644 | iteration); | 
| 645 | painCave.isFatal = 1; | 
| 646 | simError(); | 
| 647 | } | 
| 648 | } | 
| 649 |  | 
| 650 | 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 | 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 | 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 | for (i = 0; i < 3; i++){ | 
| 701 | for (j = 0; j < 3; j++){ | 
| 702 | tempA[j][i] = A[i][j]; | 
| 703 | } | 
| 704 | } | 
| 705 |  | 
| 706 | // initialize the tempJ | 
| 707 |  | 
| 708 | for (i = 0; i < 3; i++) | 
| 709 | tempJ[i] = ji[i]; | 
| 710 |  | 
| 711 | // 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 |  | 
| 721 | rot[2][0] = 0.0; | 
| 722 | rot[2][1] = 0.0; | 
| 723 | rot[2][2] = 1.0; | 
| 724 |  | 
| 725 | // use a small angle aproximation for sin and cosine | 
| 726 |  | 
| 727 | angleSqr = angle * angle; | 
| 728 | 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 |  | 
| 741 | // rotate the momentum acoording to: ji[] = rot[][] * ji[] | 
| 742 |  | 
| 743 | for (i = 0; i < 3; i++){ | 
| 744 | ji[i] = 0.0; | 
| 745 | for (k = 0; k < 3; k++){ | 
| 746 | 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 | // NOte for as yet unknown reason, we are performing the | 
| 755 | // calculation as: | 
| 756 | //                transpose(A[][]) = transpose(A[][]) * transpose(rot[][]) | 
| 757 |  | 
| 758 | for (i = 0; i < 3; i++){ | 
| 759 | for (j = 0; j < 3; j++){ | 
| 760 | A[j][i] = 0.0; | 
| 761 | for (k = 0; k < 3; k++){ | 
| 762 | A[j][i] += tempA[i][k] * rot[j][k]; | 
| 763 | } | 
| 764 | } | 
| 765 | } | 
| 766 | } | 
| 767 |  | 
| 768 | template<typename T> void Integrator<T>::calcForce(int calcPot, int calcStress){ | 
| 769 | myFF->doForces(calcPot, calcStress); | 
| 770 | } | 
| 771 |  | 
| 772 | template<typename T> void Integrator<T>::thermalize(){ | 
| 773 | tStats->velocitize(); | 
| 774 | } | 
| 775 |  | 
| 776 | template<typename T> double Integrator<T>::getConservedQuantity(void){ | 
| 777 | return tStats->getTotalE(); | 
| 778 | } | 
| 779 | template<typename T> string Integrator<T>::getAdditionalParameters(void){ | 
| 780 | //By default, return a null string | 
| 781 | //The reason we use string instead of char* is that if we use char*, we will | 
| 782 | //return a pointer point to local variable which might cause problem | 
| 783 | return string(); | 
| 784 | } |