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40 #include "gromacs/domdec/domdec.h"
41 #include "gromacs/fileio/confio.h"
42 #include "gromacs/fileio/gmxfio.h"
43 #include "gromacs/fileio/trnio.h"
44 #include "gromacs/fileio/xtcio.h"
45 #include "gromacs/legacyheaders/calcmu.h"
46 #include "gromacs/legacyheaders/chargegroup.h"
47 #include "gromacs/legacyheaders/constr.h"
48 #include "gromacs/legacyheaders/disre.h"
49 #include "gromacs/legacyheaders/force.h"
50 #include "gromacs/legacyheaders/macros.h"
51 #include "gromacs/legacyheaders/mdatoms.h"
52 #include "gromacs/legacyheaders/mdrun.h"
53 #include "gromacs/legacyheaders/names.h"
54 #include "gromacs/legacyheaders/network.h"
55 #include "gromacs/legacyheaders/nrnb.h"
56 #include "gromacs/legacyheaders/orires.h"
57 #include "gromacs/legacyheaders/txtdump.h"
58 #include "gromacs/legacyheaders/typedefs.h"
59 #include "gromacs/legacyheaders/update.h"
60 #include "gromacs/math/units.h"
61 #include "gromacs/math/vec.h"
62 #include "gromacs/random/random.h"
63 #include "gromacs/timing/wallcycle.h"
64 #include "gromacs/utility/fatalerror.h"
65 #include "gromacs/utility/gmxmpi.h"
66 #include "gromacs/utility/smalloc.h"
68 static void init_df_history_weights(df_history_t *dfhist, t_expanded *expand, int nlim)
71 dfhist->wl_delta = expand->init_wl_delta;
72 for (i = 0; i < nlim; i++)
74 dfhist->sum_weights[i] = expand->init_lambda_weights[i];
75 dfhist->sum_dg[i] = expand->init_lambda_weights[i];
79 /* Eventually should contain all the functions needed to initialize expanded ensemble
80 before the md loop starts */
81 extern void init_expanded_ensemble(gmx_bool bStateFromCP, t_inputrec *ir, df_history_t *dfhist)
85 init_df_history_weights(dfhist, ir->expandedvals, ir->fepvals->n_lambda);
89 static void GenerateGibbsProbabilities(real *ene, double *p_k, double *pks, int minfep, int maxfep)
97 /* find the maximum value */
98 for (i = minfep; i <= maxfep; i++)
105 /* find the denominator */
106 for (i = minfep; i <= maxfep; i++)
108 *pks += exp(ene[i]-maxene);
111 for (i = minfep; i <= maxfep; i++)
113 p_k[i] = exp(ene[i]-maxene) / *pks;
117 static void GenerateWeightedGibbsProbabilities(real *ene, double *p_k, double *pks, int nlim, real *nvals, real delta)
126 for (i = 0; i < nlim; i++)
130 /* add the delta, since we need to make sure it's greater than zero, and
131 we need a non-arbitrary number? */
132 nene[i] = ene[i] + log(nvals[i]+delta);
136 nene[i] = ene[i] + log(nvals[i]);
140 /* find the maximum value */
142 for (i = 0; i < nlim; i++)
144 if (nene[i] > maxene)
150 /* subtract off the maximum, avoiding overflow */
151 for (i = 0; i < nlim; i++)
156 /* find the denominator */
157 for (i = 0; i < nlim; i++)
159 *pks += exp(nene[i]);
163 for (i = 0; i < nlim; i++)
165 p_k[i] = exp(nene[i]) / *pks;
170 real do_logsum(int N, real *a_n)
174 /* log(\sum_{i=0}^(N-1) exp[a_n]) */
179 /* compute maximum argument to exp(.) */
182 for (i = 1; i < N; i++)
184 maxarg = max(maxarg, a_n[i]);
187 /* compute sum of exp(a_n - maxarg) */
189 for (i = 0; i < N; i++)
191 sum = sum + exp(a_n[i] - maxarg);
194 /* compute log sum */
195 logsum = log(sum) + maxarg;
199 int FindMinimum(real *min_metric, int N)
206 min_val = min_metric[0];
208 for (nval = 0; nval < N; nval++)
210 if (min_metric[nval] < min_val)
212 min_val = min_metric[nval];
219 static gmx_bool CheckHistogramRatios(int nhisto, real *histo, real ratio)
227 for (i = 0; i < nhisto; i++)
234 /* no samples! is bad!*/
238 nmean /= (real)nhisto;
241 for (i = 0; i < nhisto; i++)
243 /* make sure that all points are in the ratio < x < 1/ratio range */
244 if (!((histo[i]/nmean < 1.0/ratio) && (histo[i]/nmean > ratio)))
253 static gmx_bool CheckIfDoneEquilibrating(int nlim, t_expanded *expand, df_history_t *dfhist, gmx_int64_t step)
257 gmx_bool bDoneEquilibrating = TRUE;
260 /* assume we have equilibrated the weights, then check to see if any of the conditions are not met */
262 /* calculate the total number of samples */
263 switch (expand->elmceq)
266 /* We have not equilibrated, and won't, ever. */
269 /* we have equilibrated -- we're done */
272 /* first, check if we are equilibrating by steps, if we're still under */
273 if (step < expand->equil_steps)
275 bDoneEquilibrating = FALSE;
280 for (i = 0; i < nlim; i++)
282 totalsamples += dfhist->n_at_lam[i];
284 if (totalsamples < expand->equil_samples)
286 bDoneEquilibrating = FALSE;
290 for (i = 0; i < nlim; i++)
292 if (dfhist->n_at_lam[i] < expand->equil_n_at_lam) /* we are still doing the initial sweep, so we're definitely not
295 bDoneEquilibrating = FALSE;
301 if (EWL(expand->elamstats)) /* This check is in readir as well, but
304 if (dfhist->wl_delta > expand->equil_wl_delta)
306 bDoneEquilibrating = FALSE;
311 /* we can use the flatness as a judge of good weights, as long as
312 we're not doing minvar, or Wang-Landau.
313 But turn off for now until we figure out exactly how we do this.
316 if (!(EWL(expand->elamstats) || expand->elamstats == elamstatsMINVAR))
318 /* we want to use flatness -avoiding- the forced-through samples. Plus, we need to convert to
319 floats for this histogram function. */
322 snew(modhisto, nlim);
323 for (i = 0; i < nlim; i++)
325 modhisto[i] = 1.0*(dfhist->n_at_lam[i]-expand->lmc_forced_nstart);
327 bIfFlat = CheckHistogramRatios(nlim, modhisto, expand->equil_ratio);
331 bDoneEquilibrating = FALSE;
335 bDoneEquilibrating = TRUE;
337 /* one last case to go though, if we are doing slow growth to get initial values, we haven't finished equilibrating */
339 if (expand->lmc_forced_nstart > 0)
341 for (i = 0; i < nlim; i++)
343 if (dfhist->n_at_lam[i] < expand->lmc_forced_nstart) /* we are still doing the initial sweep, so we're definitely not
346 bDoneEquilibrating = FALSE;
351 return bDoneEquilibrating;
354 static gmx_bool UpdateWeights(int nlim, t_expanded *expand, df_history_t *dfhist,
355 int fep_state, real *scaled_lamee, real *weighted_lamee, gmx_int64_t step)
357 real maxdiff = 0.000000001;
358 gmx_bool bSufficientSamples;
359 int i, k, n, nz, indexi, indexk, min_n, max_n, totali;
360 int n0, np1, nm1, nval, min_nvalm, min_nvalp, maxc;
361 real omega_m1_0, omega_p1_m1, omega_m1_p1, omega_p1_0, clam_osum;
362 real de, de_function, dr, denom, maxdr;
363 real min_val, cnval, zero_sum_weights;
364 real *omegam_array, *weightsm_array, *omegap_array, *weightsp_array, *varm_array, *varp_array, *dwp_array, *dwm_array;
365 real clam_varm, clam_varp, clam_weightsm, clam_weightsp, clam_minvar;
366 real *lam_weights, *lam_minvar_corr, *lam_variance, *lam_dg;
369 real *numweighted_lamee, *logfrac;
371 real chi_m1_0, chi_p1_0, chi_m2_0, chi_p2_0, chi_p1_m1, chi_p2_m1, chi_m1_p1, chi_m2_p1;
373 /* if we have equilibrated the weights, exit now */
379 if (CheckIfDoneEquilibrating(nlim, expand, dfhist, step))
381 dfhist->bEquil = TRUE;
382 /* zero out the visited states so we know how many equilibrated states we have
384 for (i = 0; i < nlim; i++)
386 dfhist->n_at_lam[i] = 0;
391 /* If we reached this far, we have not equilibrated yet, keep on
392 going resetting the weights */
394 if (EWL(expand->elamstats))
396 if (expand->elamstats == elamstatsWL) /* Standard Wang-Landau */
398 dfhist->sum_weights[fep_state] -= dfhist->wl_delta;
399 dfhist->wl_histo[fep_state] += 1.0;
401 else if (expand->elamstats == elamstatsWWL) /* Weighted Wang-Landau */
405 /* first increment count */
406 GenerateGibbsProbabilities(weighted_lamee, p_k, &pks, 0, nlim-1);
407 for (i = 0; i < nlim; i++)
409 dfhist->wl_histo[i] += (real)p_k[i];
412 /* then increment weights (uses count) */
414 GenerateWeightedGibbsProbabilities(weighted_lamee, p_k, &pks, nlim, dfhist->wl_histo, dfhist->wl_delta);
416 for (i = 0; i < nlim; i++)
418 dfhist->sum_weights[i] -= dfhist->wl_delta*(real)p_k[i];
420 /* Alternate definition, using logarithms. Shouldn't make very much difference! */
425 di = (real)1.0 + dfhist->wl_delta*(real)p_k[i];
426 dfhist->sum_weights[i] -= log(di);
432 zero_sum_weights = dfhist->sum_weights[0];
433 for (i = 0; i < nlim; i++)
435 dfhist->sum_weights[i] -= zero_sum_weights;
439 if (expand->elamstats == elamstatsBARKER || expand->elamstats == elamstatsMETROPOLIS || expand->elamstats == elamstatsMINVAR)
442 de_function = 0; /* to get rid of warnings, but this value will not be used because of the logic */
443 maxc = 2*expand->c_range+1;
446 snew(lam_variance, nlim);
448 snew(omegap_array, maxc);
449 snew(weightsp_array, maxc);
450 snew(varp_array, maxc);
451 snew(dwp_array, maxc);
453 snew(omegam_array, maxc);
454 snew(weightsm_array, maxc);
455 snew(varm_array, maxc);
456 snew(dwm_array, maxc);
458 /* unpack the current lambdas -- we will only update 2 of these */
460 for (i = 0; i < nlim-1; i++)
461 { /* only through the second to last */
462 lam_dg[i] = dfhist->sum_dg[i+1] - dfhist->sum_dg[i];
463 lam_variance[i] = pow(dfhist->sum_variance[i+1], 2) - pow(dfhist->sum_variance[i], 2);
466 /* accumulate running averages */
467 for (nval = 0; nval < maxc; nval++)
469 /* constants for later use */
470 cnval = (real)(nval-expand->c_range);
471 /* actually, should be able to rewrite it w/o exponential, for better numerical stability */
474 de = exp(cnval - (scaled_lamee[fep_state]-scaled_lamee[fep_state-1]));
475 if (expand->elamstats == elamstatsBARKER || expand->elamstats == elamstatsMINVAR)
477 de_function = 1.0/(1.0+de);
479 else if (expand->elamstats == elamstatsMETROPOLIS)
487 de_function = 1.0/de;
490 dfhist->accum_m[fep_state][nval] += de_function;
491 dfhist->accum_m2[fep_state][nval] += de_function*de_function;
494 if (fep_state < nlim-1)
496 de = exp(-cnval + (scaled_lamee[fep_state+1]-scaled_lamee[fep_state]));
497 if (expand->elamstats == elamstatsBARKER || expand->elamstats == elamstatsMINVAR)
499 de_function = 1.0/(1.0+de);
501 else if (expand->elamstats == elamstatsMETROPOLIS)
509 de_function = 1.0/de;
512 dfhist->accum_p[fep_state][nval] += de_function;
513 dfhist->accum_p2[fep_state][nval] += de_function*de_function;
516 /* Metropolis transition and Barker transition (unoptimized Bennett) acceptance weight determination */
518 n0 = dfhist->n_at_lam[fep_state];
521 nm1 = dfhist->n_at_lam[fep_state-1];
527 if (fep_state < nlim-1)
529 np1 = dfhist->n_at_lam[fep_state+1];
536 /* logic SHOULD keep these all set correctly whatever the logic, but apparently it can't figure it out. */
537 chi_m1_0 = chi_p1_0 = chi_m2_0 = chi_p2_0 = chi_p1_m1 = chi_p2_m1 = chi_m1_p1 = chi_m2_p1 = 0;
541 chi_m1_0 = dfhist->accum_m[fep_state][nval]/n0;
542 chi_p1_0 = dfhist->accum_p[fep_state][nval]/n0;
543 chi_m2_0 = dfhist->accum_m2[fep_state][nval]/n0;
544 chi_p2_0 = dfhist->accum_p2[fep_state][nval]/n0;
547 if ((fep_state > 0 ) && (nm1 > 0))
549 chi_p1_m1 = dfhist->accum_p[fep_state-1][nval]/nm1;
550 chi_p2_m1 = dfhist->accum_p2[fep_state-1][nval]/nm1;
553 if ((fep_state < nlim-1) && (np1 > 0))
555 chi_m1_p1 = dfhist->accum_m[fep_state+1][nval]/np1;
556 chi_m2_p1 = dfhist->accum_m2[fep_state+1][nval]/np1;
570 omega_m1_0 = chi_m2_0/(chi_m1_0*chi_m1_0) - 1.0;
574 omega_p1_m1 = chi_p2_m1/(chi_p1_m1*chi_p1_m1) - 1.0;
576 if ((n0 > 0) && (nm1 > 0))
578 clam_weightsm = (log(chi_m1_0) - log(chi_p1_m1)) + cnval;
579 clam_varm = (1.0/n0)*(omega_m1_0) + (1.0/nm1)*(omega_p1_m1);
583 if (fep_state < nlim-1)
587 omega_p1_0 = chi_p2_0/(chi_p1_0*chi_p1_0) - 1.0;
591 omega_m1_p1 = chi_m2_p1/(chi_m1_p1*chi_m1_p1) - 1.0;
593 if ((n0 > 0) && (np1 > 0))
595 clam_weightsp = (log(chi_m1_p1) - log(chi_p1_0)) + cnval;
596 clam_varp = (1.0/np1)*(omega_m1_p1) + (1.0/n0)*(omega_p1_0);
602 omegam_array[nval] = omega_m1_0;
606 omegam_array[nval] = 0;
608 weightsm_array[nval] = clam_weightsm;
609 varm_array[nval] = clam_varm;
612 dwm_array[nval] = fabs( (cnval + log((1.0*n0)/nm1)) - lam_dg[fep_state-1] );
616 dwm_array[nval] = fabs( cnval - lam_dg[fep_state-1] );
621 omegap_array[nval] = omega_p1_0;
625 omegap_array[nval] = 0;
627 weightsp_array[nval] = clam_weightsp;
628 varp_array[nval] = clam_varp;
629 if ((np1 > 0) && (n0 > 0))
631 dwp_array[nval] = fabs( (cnval + log((1.0*np1)/n0)) - lam_dg[fep_state] );
635 dwp_array[nval] = fabs( cnval - lam_dg[fep_state] );
640 /* find the C's closest to the old weights value */
642 min_nvalm = FindMinimum(dwm_array, maxc);
643 omega_m1_0 = omegam_array[min_nvalm];
644 clam_weightsm = weightsm_array[min_nvalm];
645 clam_varm = varm_array[min_nvalm];
647 min_nvalp = FindMinimum(dwp_array, maxc);
648 omega_p1_0 = omegap_array[min_nvalp];
649 clam_weightsp = weightsp_array[min_nvalp];
650 clam_varp = varp_array[min_nvalp];
652 clam_osum = omega_m1_0 + omega_p1_0;
656 clam_minvar = 0.5*log(clam_osum);
661 lam_dg[fep_state-1] = clam_weightsm;
662 lam_variance[fep_state-1] = clam_varm;
665 if (fep_state < nlim-1)
667 lam_dg[fep_state] = clam_weightsp;
668 lam_variance[fep_state] = clam_varp;
671 if (expand->elamstats == elamstatsMINVAR)
673 bSufficientSamples = TRUE;
674 /* make sure they are all past a threshold */
675 for (i = 0; i < nlim; i++)
677 if (dfhist->n_at_lam[i] < expand->minvarmin)
679 bSufficientSamples = FALSE;
682 if (bSufficientSamples)
684 dfhist->sum_minvar[fep_state] = clam_minvar;
687 for (i = 0; i < nlim; i++)
689 dfhist->sum_minvar[i] += (expand->minvar_const-clam_minvar);
691 expand->minvar_const = clam_minvar;
692 dfhist->sum_minvar[fep_state] = 0.0;
696 dfhist->sum_minvar[fep_state] -= expand->minvar_const;
701 /* we need to rezero minvar now, since it could change at fep_state = 0 */
702 dfhist->sum_dg[0] = 0.0;
703 dfhist->sum_variance[0] = 0.0;
704 dfhist->sum_weights[0] = dfhist->sum_dg[0] + dfhist->sum_minvar[0]; /* should be zero */
706 for (i = 1; i < nlim; i++)
708 dfhist->sum_dg[i] = lam_dg[i-1] + dfhist->sum_dg[i-1];
709 dfhist->sum_variance[i] = sqrt(lam_variance[i-1] + pow(dfhist->sum_variance[i-1], 2));
710 dfhist->sum_weights[i] = dfhist->sum_dg[i] + dfhist->sum_minvar[i];
717 sfree(weightsm_array);
722 sfree(weightsp_array);
729 static int ChooseNewLambda(int nlim, t_expanded *expand, df_history_t *dfhist, int fep_state, real *weighted_lamee, double *p_k,
730 gmx_int64_t seed, gmx_int64_t step)
732 /* Choose new lambda value, and update transition matrix */
734 int i, ifep, jfep, minfep, maxfep, lamnew, lamtrial, starting_fep_state;
735 real r1, r2, de_old, de_new, de, trialprob, tprob = 0;
737 double *propose, *accept, *remainder;
740 gmx_bool bRestricted;
742 starting_fep_state = fep_state;
743 lamnew = fep_state; /* so that there is a default setting -- stays the same */
745 if (!EWL(expand->elamstats)) /* ignore equilibrating the weights if using WL */
747 if ((expand->lmc_forced_nstart > 0) && (dfhist->n_at_lam[nlim-1] <= expand->lmc_forced_nstart))
749 /* Use a marching method to run through the lambdas and get preliminary free energy data,
750 before starting 'free' sampling. We start free sampling when we have enough at each lambda */
752 /* if we have enough at this lambda, move on to the next one */
754 if (dfhist->n_at_lam[fep_state] == expand->lmc_forced_nstart)
756 lamnew = fep_state+1;
757 if (lamnew == nlim) /* whoops, stepped too far! */
772 snew(remainder, nlim);
774 for (i = 0; i < expand->lmc_repeats; i++)
778 gmx_rng_cycle_2uniform(step, i, seed, RND_SEED_EXPANDED, rnd);
780 for (ifep = 0; ifep < nlim; ifep++)
786 if ((expand->elmcmove == elmcmoveGIBBS) || (expand->elmcmove == elmcmoveMETGIBBS))
789 /* use the Gibbs sampler, with restricted range */
790 if (expand->gibbsdeltalam < 0)
798 minfep = fep_state - expand->gibbsdeltalam;
799 maxfep = fep_state + expand->gibbsdeltalam;
810 GenerateGibbsProbabilities(weighted_lamee, p_k, &pks, minfep, maxfep);
812 if (expand->elmcmove == elmcmoveGIBBS)
814 for (ifep = minfep; ifep <= maxfep; ifep++)
816 propose[ifep] = p_k[ifep];
821 for (lamnew = minfep; lamnew <= maxfep; lamnew++)
823 if (r1 <= p_k[lamnew])
830 else if (expand->elmcmove == elmcmoveMETGIBBS)
833 /* Metropolized Gibbs sampling */
834 for (ifep = minfep; ifep <= maxfep; ifep++)
836 remainder[ifep] = 1 - p_k[ifep];
839 /* find the proposal probabilities */
841 if (remainder[fep_state] == 0)
843 /* only the current state has any probability */
844 /* we have to stay at the current state */
849 for (ifep = minfep; ifep <= maxfep; ifep++)
851 if (ifep != fep_state)
853 propose[ifep] = p_k[ifep]/remainder[fep_state];
862 for (lamtrial = minfep; lamtrial <= maxfep; lamtrial++)
864 pnorm = p_k[lamtrial]/remainder[fep_state];
865 if (lamtrial != fep_state)
875 /* we have now selected lamtrial according to p(lamtrial)/1-p(fep_state) */
877 /* trial probability is min{1,\frac{1 - p(old)}{1-p(new)} MRS 1/8/2008 */
878 trialprob = (remainder[fep_state])/(remainder[lamtrial]);
879 if (trialprob < tprob)
894 /* now figure out the acceptance probability for each */
895 for (ifep = minfep; ifep <= maxfep; ifep++)
898 if (remainder[ifep] != 0)
900 trialprob = (remainder[fep_state])/(remainder[ifep]);
904 trialprob = 1.0; /* this state is the only choice! */
906 if (trialprob < tprob)
910 /* probability for fep_state=0, but that's fine, it's never proposed! */
911 accept[ifep] = tprob;
917 /* it's possible some rounding is failing */
918 if (gmx_within_tol(remainder[fep_state], 0, 50*GMX_DOUBLE_EPS))
920 /* numerical rounding error -- no state other than the original has weight */
925 /* probably not a numerical issue */
927 int nerror = 200+(maxfep-minfep+1)*60;
929 snew(errorstr, nerror);
930 /* if its greater than maxfep, then something went wrong -- probably underflow in the calculation
931 of sum weights. Generated detailed info for failure */
932 loc += sprintf(errorstr, "Something wrong in choosing new lambda state with a Gibbs move -- probably underflow in weight determination.\nDenominator is: %3d%17.10e\n i dE numerator weights\n", 0, pks);
933 for (ifep = minfep; ifep <= maxfep; ifep++)
935 loc += sprintf(&errorstr[loc], "%3d %17.10e%17.10e%17.10e\n", ifep, weighted_lamee[ifep], p_k[ifep], dfhist->sum_weights[ifep]);
937 gmx_fatal(FARGS, errorstr);
941 else if ((expand->elmcmove == elmcmoveMETROPOLIS) || (expand->elmcmove == elmcmoveBARKER))
943 /* use the metropolis sampler with trial +/- 1 */
949 lamtrial = fep_state;
953 lamtrial = fep_state-1;
958 if (fep_state == nlim-1)
960 lamtrial = fep_state;
964 lamtrial = fep_state+1;
968 de = weighted_lamee[lamtrial] - weighted_lamee[fep_state];
969 if (expand->elmcmove == elmcmoveMETROPOLIS)
973 if (trialprob < tprob)
977 propose[fep_state] = 0;
978 propose[lamtrial] = 1.0; /* note that this overwrites the above line if fep_state = ntrial, which only occurs at the ends */
979 accept[fep_state] = 1.0; /* doesn't actually matter, never proposed unless fep_state = ntrial, in which case it's 1.0 anyway */
980 accept[lamtrial] = tprob;
983 else if (expand->elmcmove == elmcmoveBARKER)
985 tprob = 1.0/(1.0+exp(-de));
987 propose[fep_state] = (1-tprob);
988 propose[lamtrial] += tprob; /* we add, to account for the fact that at the end, they might be the same point */
989 accept[fep_state] = 1.0;
990 accept[lamtrial] = 1.0;
1004 for (ifep = 0; ifep < nlim; ifep++)
1006 dfhist->Tij[fep_state][ifep] += propose[ifep]*accept[ifep];
1007 dfhist->Tij[fep_state][fep_state] += propose[ifep]*(1.0-accept[ifep]);
1012 dfhist->Tij_empirical[starting_fep_state][lamnew] += 1.0;
1021 /* print out the weights to the log, along with current state */
1022 extern void PrintFreeEnergyInfoToFile(FILE *outfile, t_lambda *fep, t_expanded *expand, t_simtemp *simtemp, df_history_t *dfhist,
1023 int fep_state, int frequency, gmx_int64_t step)
1025 int nlim, i, ifep, jfep;
1026 real dw, dg, dv, dm, Tprint;
1028 const char *print_names[efptNR] = {" FEPL", "MassL", "CoulL", " VdwL", "BondL", "RestT", "Temp.(K)"};
1029 gmx_bool bSimTemp = FALSE;
1031 nlim = fep->n_lambda;
1032 if (simtemp != NULL)
1037 if (mod(step, frequency) == 0)
1039 fprintf(outfile, " MC-lambda information\n");
1040 if (EWL(expand->elamstats) && (!(dfhist->bEquil)))
1042 fprintf(outfile, " Wang-Landau incrementor is: %11.5g\n", dfhist->wl_delta);
1044 fprintf(outfile, " N");
1045 for (i = 0; i < efptNR; i++)
1047 if (fep->separate_dvdl[i])
1049 fprintf(outfile, "%7s", print_names[i]);
1051 else if ((i == efptTEMPERATURE) && bSimTemp)
1053 fprintf(outfile, "%10s", print_names[i]); /* more space for temperature formats */
1056 fprintf(outfile, " Count ");
1057 if (expand->elamstats == elamstatsMINVAR)
1059 fprintf(outfile, "W(in kT) G(in kT) dG(in kT) dV(in kT)\n");
1063 fprintf(outfile, "G(in kT) dG(in kT)\n");
1065 for (ifep = 0; ifep < nlim; ifep++)
1076 dw = dfhist->sum_weights[ifep+1] - dfhist->sum_weights[ifep];
1077 dg = dfhist->sum_dg[ifep+1] - dfhist->sum_dg[ifep];
1078 dv = sqrt(pow(dfhist->sum_variance[ifep+1], 2) - pow(dfhist->sum_variance[ifep], 2));
1079 dm = dfhist->sum_minvar[ifep+1] - dfhist->sum_minvar[ifep];
1082 fprintf(outfile, "%3d", (ifep+1));
1083 for (i = 0; i < efptNR; i++)
1085 if (fep->separate_dvdl[i])
1087 fprintf(outfile, "%7.3f", fep->all_lambda[i][ifep]);
1089 else if (i == efptTEMPERATURE && bSimTemp)
1091 fprintf(outfile, "%9.3f", simtemp->temperatures[ifep]);
1094 if (EWL(expand->elamstats) && (!(dfhist->bEquil))) /* if performing WL and still haven't equilibrated */
1096 if (expand->elamstats == elamstatsWL)
1098 fprintf(outfile, " %8d", (int)dfhist->wl_histo[ifep]);
1102 fprintf(outfile, " %8.3f", dfhist->wl_histo[ifep]);
1105 else /* we have equilibrated weights */
1107 fprintf(outfile, " %8d", dfhist->n_at_lam[ifep]);
1109 if (expand->elamstats == elamstatsMINVAR)
1111 fprintf(outfile, " %10.5f %10.5f %10.5f %10.5f", dfhist->sum_weights[ifep], dfhist->sum_dg[ifep], dg, dv);
1115 fprintf(outfile, " %10.5f %10.5f", dfhist->sum_weights[ifep], dw);
1117 if (ifep == fep_state)
1119 fprintf(outfile, " <<\n");
1123 fprintf(outfile, " \n");
1126 fprintf(outfile, "\n");
1128 if ((mod(step, expand->nstTij) == 0) && (expand->nstTij > 0) && (step > 0))
1130 fprintf(outfile, " Transition Matrix\n");
1131 for (ifep = 0; ifep < nlim; ifep++)
1133 fprintf(outfile, "%12d", (ifep+1));
1135 fprintf(outfile, "\n");
1136 for (ifep = 0; ifep < nlim; ifep++)
1138 for (jfep = 0; jfep < nlim; jfep++)
1140 if (dfhist->n_at_lam[ifep] > 0)
1142 if (expand->bSymmetrizedTMatrix)
1144 Tprint = (dfhist->Tij[ifep][jfep]+dfhist->Tij[jfep][ifep])/(dfhist->n_at_lam[ifep]+dfhist->n_at_lam[jfep]);
1148 Tprint = (dfhist->Tij[ifep][jfep])/(dfhist->n_at_lam[ifep]);
1155 fprintf(outfile, "%12.8f", Tprint);
1157 fprintf(outfile, "%3d\n", (ifep+1));
1160 fprintf(outfile, " Empirical Transition Matrix\n");
1161 for (ifep = 0; ifep < nlim; ifep++)
1163 fprintf(outfile, "%12d", (ifep+1));
1165 fprintf(outfile, "\n");
1166 for (ifep = 0; ifep < nlim; ifep++)
1168 for (jfep = 0; jfep < nlim; jfep++)
1170 if (dfhist->n_at_lam[ifep] > 0)
1172 if (expand->bSymmetrizedTMatrix)
1174 Tprint = (dfhist->Tij_empirical[ifep][jfep]+dfhist->Tij_empirical[jfep][ifep])/(dfhist->n_at_lam[ifep]+dfhist->n_at_lam[jfep]);
1178 Tprint = dfhist->Tij_empirical[ifep][jfep]/(dfhist->n_at_lam[ifep]);
1185 fprintf(outfile, "%12.8f", Tprint);
1187 fprintf(outfile, "%3d\n", (ifep+1));
1193 extern int ExpandedEnsembleDynamics(FILE *log, t_inputrec *ir, gmx_enerdata_t *enerd,
1194 t_state *state, t_extmass *MassQ, int fep_state, df_history_t *dfhist,
1196 rvec *v, t_mdatoms *mdatoms)
1197 /* Note that the state variable is only needed for simulated tempering, not
1198 Hamiltonian expanded ensemble. May be able to remove it after integrator refactoring. */
1200 real *pfep_lamee, *scaled_lamee, *weighted_lamee;
1202 int i, nlim, lamnew, totalsamples;
1203 real oneovert, maxscaled = 0, maxweighted = 0;
1206 double *temperature_lambdas;
1207 gmx_bool bIfReset, bSwitchtoOneOverT, bDoneEquilibrating = FALSE;
1209 expand = ir->expandedvals;
1210 simtemp = ir->simtempvals;
1211 nlim = ir->fepvals->n_lambda;
1213 snew(scaled_lamee, nlim);
1214 snew(weighted_lamee, nlim);
1215 snew(pfep_lamee, nlim);
1218 /* update the count at the current lambda*/
1219 dfhist->n_at_lam[fep_state]++;
1221 /* need to calculate the PV term somewhere, but not needed here? Not until there's a lambda state that's
1222 pressure controlled.*/
1225 where does this PV term go?
1226 for (i=0;i<nlim;i++)
1228 fep_lamee[i] += pVTerm;
1232 /* determine the minimum value to avoid overflow. Probably a better way to do this */
1233 /* we don't need to include the pressure term, since the volume is the same between the two.
1234 is there some term we are neglecting, however? */
1236 if (ir->efep != efepNO)
1238 for (i = 0; i < nlim; i++)
1242 /* Note -- this assumes no mass changes, since kinetic energy is not added . . . */
1243 scaled_lamee[i] = (enerd->enerpart_lambda[i+1]-enerd->enerpart_lambda[0])/(simtemp->temperatures[i]*BOLTZ)
1244 + enerd->term[F_EPOT]*(1.0/(simtemp->temperatures[i])- 1.0/(simtemp->temperatures[fep_state]))/BOLTZ;
1248 scaled_lamee[i] = (enerd->enerpart_lambda[i+1]-enerd->enerpart_lambda[0])/(expand->mc_temp*BOLTZ);
1249 /* mc_temp is currently set to the system reft unless otherwise defined */
1252 /* save these energies for printing, so they don't get overwritten by the next step */
1253 /* they aren't overwritten in the non-free energy case, but we always print with these
1261 for (i = 0; i < nlim; i++)
1263 scaled_lamee[i] = enerd->term[F_EPOT]*(1.0/simtemp->temperatures[i] - 1.0/simtemp->temperatures[fep_state])/BOLTZ;
1268 for (i = 0; i < nlim; i++)
1270 pfep_lamee[i] = scaled_lamee[i];
1272 weighted_lamee[i] = dfhist->sum_weights[i] - scaled_lamee[i];
1275 maxscaled = scaled_lamee[i];
1276 maxweighted = weighted_lamee[i];
1280 if (scaled_lamee[i] > maxscaled)
1282 maxscaled = scaled_lamee[i];
1284 if (weighted_lamee[i] > maxweighted)
1286 maxweighted = weighted_lamee[i];
1291 for (i = 0; i < nlim; i++)
1293 scaled_lamee[i] -= maxscaled;
1294 weighted_lamee[i] -= maxweighted;
1297 /* update weights - we decide whether or not to actually do this inside */
1299 bDoneEquilibrating = UpdateWeights(nlim, expand, dfhist, fep_state, scaled_lamee, weighted_lamee, step);
1300 if (bDoneEquilibrating)
1304 fprintf(log, "\nStep %d: Weights have equilibrated, using criteria: %s\n", (int)step, elmceq_names[expand->elmceq]);
1308 lamnew = ChooseNewLambda(nlim, expand, dfhist, fep_state, weighted_lamee, p_k,
1309 ir->expandedvals->lmc_seed, step);
1310 /* if using simulated tempering, we need to adjust the temperatures */
1311 if (ir->bSimTemp && (lamnew != fep_state)) /* only need to change the temperatures if we change the state */
1316 int nstart, nend, gt;
1318 snew(buf_ngtc, ir->opts.ngtc);
1320 for (i = 0; i < ir->opts.ngtc; i++)
1322 if (ir->opts.ref_t[i] > 0)
1324 told = ir->opts.ref_t[i];
1325 ir->opts.ref_t[i] = simtemp->temperatures[lamnew];
1326 buf_ngtc[i] = sqrt(ir->opts.ref_t[i]/told); /* using the buffer as temperature scaling */
1330 /* we don't need to manipulate the ekind information, as it isn't due to be reset until the next step anyway */
1333 nend = mdatoms->homenr;
1334 for (n = nstart; n < nend; n++)
1339 gt = mdatoms->cTC[n];
1341 for (d = 0; d < DIM; d++)
1343 v[n][d] *= buf_ngtc[gt];
1347 if (IR_NPT_TROTTER(ir) || IR_NPH_TROTTER(ir) || IR_NVT_TROTTER(ir))
1349 /* we need to recalculate the masses if the temperature has changed */
1350 init_npt_masses(ir, state, MassQ, FALSE);
1351 for (i = 0; i < state->nnhpres; i++)
1353 for (j = 0; j < ir->opts.nhchainlength; j++)
1355 state->nhpres_vxi[i+j] *= buf_ngtc[i];
1358 for (i = 0; i < ir->opts.ngtc; i++)
1360 for (j = 0; j < ir->opts.nhchainlength; j++)
1362 state->nosehoover_vxi[i+j] *= buf_ngtc[i];
1369 /* now check on the Wang-Landau updating critera */
1371 if (EWL(expand->elamstats))
1373 bSwitchtoOneOverT = FALSE;
1374 if (expand->bWLoneovert)
1377 for (i = 0; i < nlim; i++)
1379 totalsamples += dfhist->n_at_lam[i];
1381 oneovert = (1.0*nlim)/totalsamples;
1382 /* oneovert has decreasd by a bit since last time, so we actually make sure its within one of this number */
1383 /* switch to 1/t incrementing when wl_delta has decreased at least once, and wl_delta is now less than 1/t */
1384 if ((dfhist->wl_delta <= ((totalsamples)/(totalsamples-1.00001))*oneovert) &&
1385 (dfhist->wl_delta < expand->init_wl_delta))
1387 bSwitchtoOneOverT = TRUE;
1390 if (bSwitchtoOneOverT)
1392 dfhist->wl_delta = oneovert; /* now we reduce by this each time, instead of only at flatness */
1396 bIfReset = CheckHistogramRatios(nlim, dfhist->wl_histo, expand->wl_ratio);
1399 for (i = 0; i < nlim; i++)
1401 dfhist->wl_histo[i] = 0;
1403 dfhist->wl_delta *= expand->wl_scale;
1406 fprintf(log, "\nStep %d: weights are now:", (int)step);
1407 for (i = 0; i < nlim; i++)
1409 fprintf(log, " %.5f", dfhist->sum_weights[i]);
1417 sfree(scaled_lamee);
1418 sfree(weighted_lamee);