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38 /* This file is completely threadsafe - keep it that way! */
43 #include "gromacs/math/functions.h"
44 #include "gromacs/math/invertmatrix.h"
45 #include "gromacs/math/vec.h"
46 #include "gromacs/math/vecdump.h"
47 #include "gromacs/mdlib/gmx_omp_nthreads.h"
48 #include "gromacs/mdtypes/inputrec.h"
49 #include "gromacs/mdtypes/md_enums.h"
50 #include "gromacs/mdtypes/mdatom.h"
51 #include "gromacs/pbcutil/pbc.h"
52 #include "gromacs/topology/topology.h"
53 #include "gromacs/utility/fatalerror.h"
54 #include "gromacs/utility/gmxassert.h"
55 #include "gromacs/utility/gmxomp.h"
56 #include "gromacs/utility/smalloc.h"
58 t_vcm::t_vcm(const SimulationGroups& groups, const t_inputrec& ir) :
59 integratorConservesMomentum(!EI_RANDOM(ir.eI))
61 mode = (ir.nstcomm > 0) ? ir.comm_mode : ComRemovalAlgorithm::No;
63 timeStep = ir.nstcomm * ir.delta_t;
65 if (mode == ComRemovalAlgorithm::Angular && ndim < 3)
67 gmx_fatal(FARGS, "Can not have angular comm removal with pbc=%s", c_pbcTypeNames[ir.pbcType].c_str());
70 if (mode != ComRemovalAlgorithm::No)
72 nr = groups.groups[SimulationAtomGroupType::MassCenterVelocityRemoval].size();
73 /* Allocate one extra for a possible rest group */
75 /* We need vcm->nr+1 elements per thread, but to avoid cache
76 * invalidation we add 2 elements to get a 152 byte separation.
79 if (mode == ComRemovalAlgorithm::Angular)
88 group_name.resize(size);
91 group_mass.resize(size);
92 group_ndf.resize(size);
93 for (int g = 0; (g < nr); g++)
95 group_ndf[g] = ir.opts.nrdf[g];
97 *groups.groupNames[groups.groups[SimulationAtomGroupType::MassCenterVelocityRemoval][g]];
100 thread_vcm.resize(gmx_omp_nthreads_get(emntDefault) * stride);
103 nFreeze = ir.opts.nFreeze;
108 if (mode == ComRemovalAlgorithm::Angular)
114 void reportComRemovalInfo(FILE* fp, const t_vcm& vcm)
117 /* Copy pointer to group names and print it. */
118 if (fp && vcm.mode != ComRemovalAlgorithm::No)
120 fprintf(fp, "Center of mass motion removal mode is %s\n", enumValueToString(vcm.mode));
122 "We have the following groups for center of"
123 " mass motion removal:\n");
125 for (int g = 0; (g < vcm.nr); g++)
128 fprintf(fp, "%3d: %s\n", g, vcm.group_name[g]);
134 static void update_tensor(const rvec x, real m0, tensor I)
138 /* Compute inertia tensor contribution due to this atom */
139 xy = x[XX] * x[YY] * m0;
140 xz = x[XX] * x[ZZ] * m0;
141 yz = x[YY] * x[ZZ] * m0;
142 I[XX][XX] += x[XX] * x[XX] * m0;
143 I[YY][YY] += x[YY] * x[YY] * m0;
144 I[ZZ][ZZ] += x[ZZ] * x[ZZ] * m0;
153 /* Center of mass code for groups */
154 void calc_vcm_grp(const t_mdatoms& md,
155 gmx::ArrayRef<const gmx::RVec> x,
156 gmx::ArrayRef<const gmx::RVec> v,
159 if (vcm->mode == ComRemovalAlgorithm::No)
163 int nthreads = gmx_omp_nthreads_get(emntDefault);
166 #pragma omp parallel num_threads(nthreads) default(none) shared(x, v, vcm, md)
168 int t = gmx_omp_get_thread_num();
169 for (int g = 0; g < vcm->size; g++)
171 /* Reset linear momentum */
172 t_vcm_thread* vcm_t = &vcm->thread_vcm[t * vcm->stride + g];
174 clear_rvec(vcm_t->p);
175 if (vcm->mode == ComRemovalAlgorithm::Angular)
177 /* Reset angular momentum */
178 clear_rvec(vcm_t->j);
179 clear_rvec(vcm_t->x);
184 #pragma omp for schedule(static)
185 for (int i = 0; i < md.homenr; i++)
188 real m0 = md.massT[i];
193 t_vcm_thread* vcm_t = &vcm->thread_vcm[t * vcm->stride + g];
194 /* Calculate linear momentum */
197 for (m = 0; (m < DIM); m++)
199 vcm_t->p[m] += m0 * v[i][m];
202 if (vcm->mode == ComRemovalAlgorithm::Angular)
204 /* Calculate angular momentum */
206 cprod(x[i], v[i], j0);
208 for (m = 0; (m < DIM); m++)
210 vcm_t->j[m] += m0 * j0[m];
211 vcm_t->x[m] += m0 * x[i][m];
213 /* Update inertia tensor */
214 update_tensor(x[i], m0, vcm_t->i);
218 for (int g = 0; g < vcm->size; g++)
220 /* Reset linear momentum */
221 vcm->group_mass[g] = 0;
222 clear_rvec(vcm->group_p[g]);
223 if (vcm->mode == ComRemovalAlgorithm::Angular)
225 /* Reset angular momentum */
226 clear_rvec(vcm->group_j[g]);
227 clear_rvec(vcm->group_x[g]);
228 clear_rvec(vcm->group_w[g]);
229 clear_mat(vcm->group_i[g]);
232 for (int t = 0; t < nthreads; t++)
234 t_vcm_thread* vcm_t = &vcm->thread_vcm[t * vcm->stride + g];
235 vcm->group_mass[g] += vcm_t->mass;
236 rvec_inc(vcm->group_p[g], vcm_t->p);
237 if (vcm->mode == ComRemovalAlgorithm::Angular)
239 rvec_inc(vcm->group_j[g], vcm_t->j);
240 rvec_inc(vcm->group_x[g], vcm_t->x);
241 m_add(vcm_t->i, vcm->group_i[g], vcm->group_i[g]);
248 /*! \brief Remove the COM motion velocity from the velocities
250 * \note This routine should be called from within an OpenMP parallel region.
252 * \tparam numDimensions Correct dimensions 0 to \p numDimensions-1
253 * \param[in] mdatoms The atom property and group information
254 * \param[in,out] v The velocities to correct
255 * \param[in] vcm VCM data
257 template<int numDimensions>
258 static void doStopComMotionLinear(const t_mdatoms& mdatoms, gmx::ArrayRef<gmx::RVec> v, const t_vcm& vcm)
260 const int homenr = mdatoms.homenr;
261 const unsigned short* group_id = mdatoms.cVCM;
263 if (mdatoms.cFREEZE != nullptr)
265 GMX_RELEASE_ASSERT(vcm.nFreeze != nullptr, "Need freeze dimension info with freeze groups");
267 #pragma omp for schedule(static)
268 for (int i = 0; i < homenr; i++)
270 unsigned short vcmGroup = (group_id == nullptr ? 0 : group_id[i]);
271 unsigned short freezeGroup = mdatoms.cFREEZE[i];
272 for (int d = 0; d < numDimensions; d++)
274 if (vcm.nFreeze[freezeGroup][d] == 0)
276 v[i][d] -= vcm.group_v[vcmGroup][d];
281 else if (group_id == nullptr)
282 { // NOLINT bugprone-branch-clone This is actually a clang-tidy bug
283 #pragma omp for schedule(static)
284 for (int i = 0; i < homenr; i++)
286 for (int d = 0; d < numDimensions; d++)
288 v[i][d] -= vcm.group_v[0][d];
294 #pragma omp for schedule(static)
295 for (int i = 0; i < homenr; i++)
297 const int g = group_id[i];
298 for (int d = 0; d < numDimensions; d++)
300 v[i][d] -= vcm.group_v[g][d];
306 /*! \brief Remove the COM motion velocity from the velocities, correct the coordinates assuming constant acceleration
308 * \note This routine should be called from within an OpenMP parallel region.
310 * \tparam numDimensions Correct dimensions 0 to \p numDimensions-1
311 * \param[in] homenr The number of atoms to correct
312 * \param[in] group_id List of VCM group ids, when nullptr is passed all atoms are assumed to be in group 0
313 * \param[in,out] x The coordinates to correct
314 * \param[in,out] v The velocities to correct
315 * \param[in] vcm VCM data
317 template<int numDimensions>
318 static void doStopComMotionAccelerationCorrection(int homenr,
319 const unsigned short* group_id,
320 gmx::ArrayRef<gmx::RVec> x,
321 gmx::ArrayRef<gmx::RVec> v,
324 const real xCorrectionFactor = 0.5 * vcm.timeStep;
326 // NOLINTNEXTLINE bugprone-branch-clone This is actually a clang-tidy bug
327 if (group_id == nullptr)
329 #pragma omp for schedule(static)
330 for (int i = 0; i < homenr; i++)
332 for (int d = 0; d < numDimensions; d++)
334 x[i][d] -= vcm.group_v[0][d] * xCorrectionFactor;
335 v[i][d] -= vcm.group_v[0][d];
341 #pragma omp for schedule(static)
342 for (int i = 0; i < homenr; i++)
344 const int g = group_id[i];
345 for (int d = 0; d < numDimensions; d++)
347 x[i][d] -= vcm.group_v[g][d] * xCorrectionFactor;
348 v[i][d] -= vcm.group_v[g][d];
354 static void do_stopcm_grp(const t_mdatoms& mdatoms,
355 gmx::ArrayRef<gmx::RVec> x,
356 gmx::ArrayRef<gmx::RVec> v,
359 if (vcm.mode == ComRemovalAlgorithm::No)
364 const int homenr = mdatoms.homenr;
365 const unsigned short* group_id = mdatoms.cVCM;
367 int gmx_unused nth = gmx_omp_nthreads_get(emntDefault);
368 // homenr could be shared, but gcc-8 & gcc-9 don't agree how to write that...
369 // https://www.gnu.org/software/gcc/gcc-9/porting_to.html -> OpenMP data sharing
370 #pragma omp parallel num_threads(nth) default(none) shared(x, v, vcm, group_id, mdatoms) \
373 if (vcm.mode == ComRemovalAlgorithm::Linear || vcm.mode == ComRemovalAlgorithm::Angular
374 || (vcm.mode == ComRemovalAlgorithm::LinearAccelerationCorrection && x.empty()))
376 /* Subtract linear momentum for v */
379 case 1: doStopComMotionLinear<1>(mdatoms, v, vcm); break;
380 case 2: doStopComMotionLinear<2>(mdatoms, v, vcm); break;
381 case 3: doStopComMotionLinear<3>(mdatoms, v, vcm); break;
386 GMX_ASSERT(vcm.mode == ComRemovalAlgorithm::LinearAccelerationCorrection,
387 "When the mode is not linear or angular, it should be acceleration "
389 /* Subtract linear momentum for v and x*/
393 doStopComMotionAccelerationCorrection<1>(homenr, group_id, x, v, vcm);
396 doStopComMotionAccelerationCorrection<2>(homenr, group_id, x, v, vcm);
399 doStopComMotionAccelerationCorrection<3>(homenr, group_id, x, v, vcm);
403 if (vcm.mode == ComRemovalAlgorithm::Angular)
405 /* Subtract angular momentum */
406 GMX_ASSERT(!x.empty(), "Need x to compute angular momentum correction");
409 #pragma omp for schedule(static)
410 for (int i = 0; i < homenr; i++)
416 /* Compute the correction to the velocity for each atom */
418 rvec_sub(x[i], vcm.group_x[g], dx);
419 cprod(vcm.group_w[g], dx, dv);
427 static void get_minv(tensor A, tensor B)
433 tmp[XX][XX] = A[YY][YY] + A[ZZ][ZZ];
434 tmp[YY][XX] = -A[XX][YY];
435 tmp[ZZ][XX] = -A[XX][ZZ];
436 tmp[XX][YY] = -A[XX][YY];
437 tmp[YY][YY] = A[XX][XX] + A[ZZ][ZZ];
438 tmp[ZZ][YY] = -A[YY][ZZ];
439 tmp[XX][ZZ] = -A[XX][ZZ];
440 tmp[YY][ZZ] = -A[YY][ZZ];
441 tmp[ZZ][ZZ] = A[XX][XX] + A[YY][YY];
443 /* This is a hack to prevent very large determinants */
444 rfac = (tmp[XX][XX] + tmp[YY][YY] + tmp[ZZ][ZZ]) / 3;
447 gmx_fatal(FARGS, "Can not stop center of mass: maybe 2dimensional system");
450 for (m = 0; (m < DIM); m++)
452 for (n = 0; (n < DIM); n++)
457 gmx::invertMatrix(tmp, B);
458 for (m = 0; (m < DIM); m++)
460 for (n = 0; (n < DIM); n++)
467 /* Processes VCM after reduction over ranks and prints warning with high VMC and fp != nullptr */
468 static void process_and_check_cm_grp(FILE* fp, t_vcm* vcm, real Temp_Max)
471 real ekcm, ekrot, tm, tm_1, Temp_cm;
475 /* First analyse the total results */
476 if (vcm->mode != ComRemovalAlgorithm::No)
478 for (g = 0; (g < vcm->nr); g++)
480 tm = vcm->group_mass[g];
484 svmul(tm_1, vcm->group_p[g], vcm->group_v[g]);
486 /* Else it's zero anyway! */
488 if (vcm->mode == ComRemovalAlgorithm::Angular)
490 for (g = 0; (g < vcm->nr); g++)
492 tm = vcm->group_mass[g];
497 /* Compute center of mass for this group */
498 for (m = 0; (m < DIM); m++)
500 vcm->group_x[g][m] *= tm_1;
503 /* Subtract the center of mass contribution to the
506 cprod(vcm->group_x[g], vcm->group_v[g], jcm);
507 for (m = 0; (m < DIM); m++)
509 vcm->group_j[g][m] -= tm * jcm[m];
512 /* Subtract the center of mass contribution from the inertia
513 * tensor (this is not as trivial as it seems, but due to
514 * some cancellation we can still do it, even in parallel).
517 update_tensor(vcm->group_x[g], tm, Icm);
518 m_sub(vcm->group_i[g], Icm, vcm->group_i[g]);
520 /* Compute angular velocity, using matrix operation
525 get_minv(vcm->group_i[g], Icm);
526 mvmul(Icm, vcm->group_j[g], vcm->group_w[g]);
528 /* Else it's zero anyway! */
532 for (g = 0; (g < vcm->nr); g++)
535 if (vcm->group_mass[g] != 0 && vcm->group_ndf[g] > 0)
537 for (m = 0; m < vcm->ndim; m++)
539 ekcm += gmx::square(vcm->group_v[g][m]);
541 ekcm *= 0.5 * vcm->group_mass[g];
542 Temp_cm = 2 * ekcm / vcm->group_ndf[g];
544 if ((Temp_cm > Temp_Max) && fp)
547 "Large VCM(group %s): %12.5f, %12.5f, %12.5f, Temp-cm: %12.5e\n",
555 if (vcm->mode == ComRemovalAlgorithm::Angular)
557 ekrot = 0.5 * iprod(vcm->group_j[g], vcm->group_w[g]);
558 // TODO: Change absolute energy comparison to relative
559 if ((ekrot > 1) && fp && vcm->integratorConservesMomentum)
561 /* if we have an integrator that may not conserve momenta, skip */
562 tm = vcm->group_mass[g];
564 "Group %s with mass %12.5e, Ekrot %12.5e Det(I) = %12.5e\n",
568 det(vcm->group_i[g]));
570 " COM: %12.5f %12.5f %12.5f\n",
573 vcm->group_x[g][ZZ]);
575 " P: %12.5f %12.5f %12.5f\n",
578 vcm->group_p[g][ZZ]);
580 " V: %12.5f %12.5f %12.5f\n",
583 vcm->group_v[g][ZZ]);
585 " J: %12.5f %12.5f %12.5f\n",
588 vcm->group_j[g][ZZ]);
590 " w: %12.5f %12.5f %12.5f\n",
593 vcm->group_w[g][ZZ]);
594 pr_rvecs(fp, 0, "Inertia tensor", vcm->group_i[g], DIM);
601 void process_and_stopcm_grp(FILE* fplog,
603 const t_mdatoms& mdatoms,
604 gmx::ArrayRef<gmx::RVec> x,
605 gmx::ArrayRef<gmx::RVec> v)
607 if (vcm->mode != ComRemovalAlgorithm::No)
609 // TODO: Replace fixed temperature of 1 by a system value
610 process_and_check_cm_grp(fplog, vcm, 1);
612 do_stopcm_grp(mdatoms, x, v, *vcm);