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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/xtcio.h"
44 #include "gromacs/legacyheaders/calcmu.h"
45 #include "gromacs/legacyheaders/chargegroup.h"
46 #include "gromacs/legacyheaders/constr.h"
47 #include "gromacs/legacyheaders/disre.h"
48 #include "gromacs/legacyheaders/force.h"
49 #include "gromacs/legacyheaders/macros.h"
50 #include "gromacs/legacyheaders/mdatoms.h"
51 #include "gromacs/legacyheaders/mdrun.h"
52 #include "gromacs/legacyheaders/names.h"
53 #include "gromacs/legacyheaders/network.h"
54 #include "gromacs/legacyheaders/nrnb.h"
55 #include "gromacs/legacyheaders/orires.h"
56 #include "gromacs/legacyheaders/txtdump.h"
57 #include "gromacs/legacyheaders/typedefs.h"
58 #include "gromacs/legacyheaders/update.h"
59 #include "gromacs/math/units.h"
60 #include "gromacs/math/vec.h"
61 #include "gromacs/random/random.h"
62 #include "gromacs/timing/wallcycle.h"
63 #include "gromacs/utility/fatalerror.h"
64 #include "gromacs/utility/gmxmpi.h"
65 #include "gromacs/utility/smalloc.h"
67 static void init_df_history_weights(df_history_t *dfhist, t_expanded *expand, int nlim)
70 dfhist->wl_delta = expand->init_wl_delta;
71 for (i = 0; i < nlim; i++)
73 dfhist->sum_weights[i] = expand->init_lambda_weights[i];
74 dfhist->sum_dg[i] = expand->init_lambda_weights[i];
78 /* Eventually should contain all the functions needed to initialize expanded ensemble
79 before the md loop starts */
80 extern void init_expanded_ensemble(gmx_bool bStateFromCP, t_inputrec *ir, df_history_t *dfhist)
84 init_df_history_weights(dfhist, ir->expandedvals, ir->fepvals->n_lambda);
88 static void GenerateGibbsProbabilities(real *ene, double *p_k, double *pks, int minfep, int maxfep)
96 /* find the maximum value */
97 for (i = minfep; i <= maxfep; i++)
104 /* find the denominator */
105 for (i = minfep; i <= maxfep; i++)
107 *pks += exp(ene[i]-maxene);
110 for (i = minfep; i <= maxfep; i++)
112 p_k[i] = exp(ene[i]-maxene) / *pks;
116 static void GenerateWeightedGibbsProbabilities(real *ene, double *p_k, double *pks, int nlim, real *nvals, real delta)
125 for (i = 0; i < nlim; i++)
129 /* add the delta, since we need to make sure it's greater than zero, and
130 we need a non-arbitrary number? */
131 nene[i] = ene[i] + log(nvals[i]+delta);
135 nene[i] = ene[i] + log(nvals[i]);
139 /* find the maximum value */
141 for (i = 0; i < nlim; i++)
143 if (nene[i] > maxene)
149 /* subtract off the maximum, avoiding overflow */
150 for (i = 0; i < nlim; i++)
155 /* find the denominator */
156 for (i = 0; i < nlim; i++)
158 *pks += exp(nene[i]);
162 for (i = 0; i < nlim; i++)
164 p_k[i] = exp(nene[i]) / *pks;
169 real do_logsum(int N, real *a_n)
173 /* log(\sum_{i=0}^(N-1) exp[a_n]) */
178 /* compute maximum argument to exp(.) */
181 for (i = 1; i < N; i++)
183 maxarg = max(maxarg, a_n[i]);
186 /* compute sum of exp(a_n - maxarg) */
188 for (i = 0; i < N; i++)
190 sum = sum + exp(a_n[i] - maxarg);
193 /* compute log sum */
194 logsum = log(sum) + maxarg;
198 int FindMinimum(real *min_metric, int N)
205 min_val = min_metric[0];
207 for (nval = 0; nval < N; nval++)
209 if (min_metric[nval] < min_val)
211 min_val = min_metric[nval];
218 static gmx_bool CheckHistogramRatios(int nhisto, real *histo, real ratio)
226 for (i = 0; i < nhisto; i++)
233 /* no samples! is bad!*/
237 nmean /= (real)nhisto;
240 for (i = 0; i < nhisto; i++)
242 /* make sure that all points are in the ratio < x < 1/ratio range */
243 if (!((histo[i]/nmean < 1.0/ratio) && (histo[i]/nmean > ratio)))
252 static gmx_bool CheckIfDoneEquilibrating(int nlim, t_expanded *expand, df_history_t *dfhist, gmx_int64_t step)
256 gmx_bool bDoneEquilibrating = TRUE;
259 /* assume we have equilibrated the weights, then check to see if any of the conditions are not met */
261 /* calculate the total number of samples */
262 switch (expand->elmceq)
265 /* We have not equilibrated, and won't, ever. */
268 /* we have equilibrated -- we're done */
271 /* first, check if we are equilibrating by steps, if we're still under */
272 if (step < expand->equil_steps)
274 bDoneEquilibrating = FALSE;
279 for (i = 0; i < nlim; i++)
281 totalsamples += dfhist->n_at_lam[i];
283 if (totalsamples < expand->equil_samples)
285 bDoneEquilibrating = FALSE;
289 for (i = 0; i < nlim; i++)
291 if (dfhist->n_at_lam[i] < expand->equil_n_at_lam) /* we are still doing the initial sweep, so we're definitely not
294 bDoneEquilibrating = FALSE;
300 if (EWL(expand->elamstats)) /* This check is in readir as well, but
303 if (dfhist->wl_delta > expand->equil_wl_delta)
305 bDoneEquilibrating = FALSE;
310 /* we can use the flatness as a judge of good weights, as long as
311 we're not doing minvar, or Wang-Landau.
312 But turn off for now until we figure out exactly how we do this.
315 if (!(EWL(expand->elamstats) || expand->elamstats == elamstatsMINVAR))
317 /* we want to use flatness -avoiding- the forced-through samples. Plus, we need to convert to
318 floats for this histogram function. */
321 snew(modhisto, nlim);
322 for (i = 0; i < nlim; i++)
324 modhisto[i] = 1.0*(dfhist->n_at_lam[i]-expand->lmc_forced_nstart);
326 bIfFlat = CheckHistogramRatios(nlim, modhisto, expand->equil_ratio);
330 bDoneEquilibrating = FALSE;
334 bDoneEquilibrating = TRUE;
336 /* one last case to go though, if we are doing slow growth to get initial values, we haven't finished equilibrating */
338 if (expand->lmc_forced_nstart > 0)
340 for (i = 0; i < nlim; i++)
342 if (dfhist->n_at_lam[i] < expand->lmc_forced_nstart) /* we are still doing the initial sweep, so we're definitely not
345 bDoneEquilibrating = FALSE;
350 return bDoneEquilibrating;
353 static gmx_bool UpdateWeights(int nlim, t_expanded *expand, df_history_t *dfhist,
354 int fep_state, real *scaled_lamee, real *weighted_lamee, gmx_int64_t step)
356 real maxdiff = 0.000000001;
357 gmx_bool bSufficientSamples;
358 int i, k, n, nz, indexi, indexk, min_n, max_n, totali;
359 int n0, np1, nm1, nval, min_nvalm, min_nvalp, maxc;
360 real omega_m1_0, omega_p1_m1, omega_m1_p1, omega_p1_0, clam_osum;
361 real de, de_function, dr, denom, maxdr;
362 real min_val, cnval, zero_sum_weights;
363 real *omegam_array, *weightsm_array, *omegap_array, *weightsp_array, *varm_array, *varp_array, *dwp_array, *dwm_array;
364 real clam_varm, clam_varp, clam_weightsm, clam_weightsp, clam_minvar;
365 real *lam_weights, *lam_minvar_corr, *lam_variance, *lam_dg;
368 real *numweighted_lamee, *logfrac;
370 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;
372 /* if we have equilibrated the weights, exit now */
378 if (CheckIfDoneEquilibrating(nlim, expand, dfhist, step))
380 dfhist->bEquil = TRUE;
381 /* zero out the visited states so we know how many equilibrated states we have
383 for (i = 0; i < nlim; i++)
385 dfhist->n_at_lam[i] = 0;
390 /* If we reached this far, we have not equilibrated yet, keep on
391 going resetting the weights */
393 if (EWL(expand->elamstats))
395 if (expand->elamstats == elamstatsWL) /* Standard Wang-Landau */
397 dfhist->sum_weights[fep_state] -= dfhist->wl_delta;
398 dfhist->wl_histo[fep_state] += 1.0;
400 else if (expand->elamstats == elamstatsWWL) /* Weighted Wang-Landau */
404 /* first increment count */
405 GenerateGibbsProbabilities(weighted_lamee, p_k, &pks, 0, nlim-1);
406 for (i = 0; i < nlim; i++)
408 dfhist->wl_histo[i] += (real)p_k[i];
411 /* then increment weights (uses count) */
413 GenerateWeightedGibbsProbabilities(weighted_lamee, p_k, &pks, nlim, dfhist->wl_histo, dfhist->wl_delta);
415 for (i = 0; i < nlim; i++)
417 dfhist->sum_weights[i] -= dfhist->wl_delta*(real)p_k[i];
419 /* Alternate definition, using logarithms. Shouldn't make very much difference! */
424 di = (real)1.0 + dfhist->wl_delta*(real)p_k[i];
425 dfhist->sum_weights[i] -= log(di);
431 zero_sum_weights = dfhist->sum_weights[0];
432 for (i = 0; i < nlim; i++)
434 dfhist->sum_weights[i] -= zero_sum_weights;
438 if (expand->elamstats == elamstatsBARKER || expand->elamstats == elamstatsMETROPOLIS || expand->elamstats == elamstatsMINVAR)
441 de_function = 0; /* to get rid of warnings, but this value will not be used because of the logic */
442 maxc = 2*expand->c_range+1;
445 snew(lam_variance, nlim);
447 snew(omegap_array, maxc);
448 snew(weightsp_array, maxc);
449 snew(varp_array, maxc);
450 snew(dwp_array, maxc);
452 snew(omegam_array, maxc);
453 snew(weightsm_array, maxc);
454 snew(varm_array, maxc);
455 snew(dwm_array, maxc);
457 /* unpack the current lambdas -- we will only update 2 of these */
459 for (i = 0; i < nlim-1; i++)
460 { /* only through the second to last */
461 lam_dg[i] = dfhist->sum_dg[i+1] - dfhist->sum_dg[i];
462 lam_variance[i] = pow(dfhist->sum_variance[i+1], 2) - pow(dfhist->sum_variance[i], 2);
465 /* accumulate running averages */
466 for (nval = 0; nval < maxc; nval++)
468 /* constants for later use */
469 cnval = (real)(nval-expand->c_range);
470 /* actually, should be able to rewrite it w/o exponential, for better numerical stability */
473 de = exp(cnval - (scaled_lamee[fep_state]-scaled_lamee[fep_state-1]));
474 if (expand->elamstats == elamstatsBARKER || expand->elamstats == elamstatsMINVAR)
476 de_function = 1.0/(1.0+de);
478 else if (expand->elamstats == elamstatsMETROPOLIS)
486 de_function = 1.0/de;
489 dfhist->accum_m[fep_state][nval] += de_function;
490 dfhist->accum_m2[fep_state][nval] += de_function*de_function;
493 if (fep_state < nlim-1)
495 de = exp(-cnval + (scaled_lamee[fep_state+1]-scaled_lamee[fep_state]));
496 if (expand->elamstats == elamstatsBARKER || expand->elamstats == elamstatsMINVAR)
498 de_function = 1.0/(1.0+de);
500 else if (expand->elamstats == elamstatsMETROPOLIS)
508 de_function = 1.0/de;
511 dfhist->accum_p[fep_state][nval] += de_function;
512 dfhist->accum_p2[fep_state][nval] += de_function*de_function;
515 /* Metropolis transition and Barker transition (unoptimized Bennett) acceptance weight determination */
517 n0 = dfhist->n_at_lam[fep_state];
520 nm1 = dfhist->n_at_lam[fep_state-1];
526 if (fep_state < nlim-1)
528 np1 = dfhist->n_at_lam[fep_state+1];
535 /* logic SHOULD keep these all set correctly whatever the logic, but apparently it can't figure it out. */
536 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;
540 chi_m1_0 = dfhist->accum_m[fep_state][nval]/n0;
541 chi_p1_0 = dfhist->accum_p[fep_state][nval]/n0;
542 chi_m2_0 = dfhist->accum_m2[fep_state][nval]/n0;
543 chi_p2_0 = dfhist->accum_p2[fep_state][nval]/n0;
546 if ((fep_state > 0 ) && (nm1 > 0))
548 chi_p1_m1 = dfhist->accum_p[fep_state-1][nval]/nm1;
549 chi_p2_m1 = dfhist->accum_p2[fep_state-1][nval]/nm1;
552 if ((fep_state < nlim-1) && (np1 > 0))
554 chi_m1_p1 = dfhist->accum_m[fep_state+1][nval]/np1;
555 chi_m2_p1 = dfhist->accum_m2[fep_state+1][nval]/np1;
569 omega_m1_0 = chi_m2_0/(chi_m1_0*chi_m1_0) - 1.0;
573 omega_p1_m1 = chi_p2_m1/(chi_p1_m1*chi_p1_m1) - 1.0;
575 if ((n0 > 0) && (nm1 > 0))
577 clam_weightsm = (log(chi_m1_0) - log(chi_p1_m1)) + cnval;
578 clam_varm = (1.0/n0)*(omega_m1_0) + (1.0/nm1)*(omega_p1_m1);
582 if (fep_state < nlim-1)
586 omega_p1_0 = chi_p2_0/(chi_p1_0*chi_p1_0) - 1.0;
590 omega_m1_p1 = chi_m2_p1/(chi_m1_p1*chi_m1_p1) - 1.0;
592 if ((n0 > 0) && (np1 > 0))
594 clam_weightsp = (log(chi_m1_p1) - log(chi_p1_0)) + cnval;
595 clam_varp = (1.0/np1)*(omega_m1_p1) + (1.0/n0)*(omega_p1_0);
601 omegam_array[nval] = omega_m1_0;
605 omegam_array[nval] = 0;
607 weightsm_array[nval] = clam_weightsm;
608 varm_array[nval] = clam_varm;
611 dwm_array[nval] = fabs( (cnval + log((1.0*n0)/nm1)) - lam_dg[fep_state-1] );
615 dwm_array[nval] = fabs( cnval - lam_dg[fep_state-1] );
620 omegap_array[nval] = omega_p1_0;
624 omegap_array[nval] = 0;
626 weightsp_array[nval] = clam_weightsp;
627 varp_array[nval] = clam_varp;
628 if ((np1 > 0) && (n0 > 0))
630 dwp_array[nval] = fabs( (cnval + log((1.0*np1)/n0)) - lam_dg[fep_state] );
634 dwp_array[nval] = fabs( cnval - lam_dg[fep_state] );
639 /* find the C's closest to the old weights value */
641 min_nvalm = FindMinimum(dwm_array, maxc);
642 omega_m1_0 = omegam_array[min_nvalm];
643 clam_weightsm = weightsm_array[min_nvalm];
644 clam_varm = varm_array[min_nvalm];
646 min_nvalp = FindMinimum(dwp_array, maxc);
647 omega_p1_0 = omegap_array[min_nvalp];
648 clam_weightsp = weightsp_array[min_nvalp];
649 clam_varp = varp_array[min_nvalp];
651 clam_osum = omega_m1_0 + omega_p1_0;
655 clam_minvar = 0.5*log(clam_osum);
660 lam_dg[fep_state-1] = clam_weightsm;
661 lam_variance[fep_state-1] = clam_varm;
664 if (fep_state < nlim-1)
666 lam_dg[fep_state] = clam_weightsp;
667 lam_variance[fep_state] = clam_varp;
670 if (expand->elamstats == elamstatsMINVAR)
672 bSufficientSamples = TRUE;
673 /* make sure they are all past a threshold */
674 for (i = 0; i < nlim; i++)
676 if (dfhist->n_at_lam[i] < expand->minvarmin)
678 bSufficientSamples = FALSE;
681 if (bSufficientSamples)
683 dfhist->sum_minvar[fep_state] = clam_minvar;
686 for (i = 0; i < nlim; i++)
688 dfhist->sum_minvar[i] += (expand->minvar_const-clam_minvar);
690 expand->minvar_const = clam_minvar;
691 dfhist->sum_minvar[fep_state] = 0.0;
695 dfhist->sum_minvar[fep_state] -= expand->minvar_const;
700 /* we need to rezero minvar now, since it could change at fep_state = 0 */
701 dfhist->sum_dg[0] = 0.0;
702 dfhist->sum_variance[0] = 0.0;
703 dfhist->sum_weights[0] = dfhist->sum_dg[0] + dfhist->sum_minvar[0]; /* should be zero */
705 for (i = 1; i < nlim; i++)
707 dfhist->sum_dg[i] = lam_dg[i-1] + dfhist->sum_dg[i-1];
708 dfhist->sum_variance[i] = sqrt(lam_variance[i-1] + pow(dfhist->sum_variance[i-1], 2));
709 dfhist->sum_weights[i] = dfhist->sum_dg[i] + dfhist->sum_minvar[i];
716 sfree(weightsm_array);
721 sfree(weightsp_array);
728 static int ChooseNewLambda(int nlim, t_expanded *expand, df_history_t *dfhist, int fep_state, real *weighted_lamee, double *p_k,
729 gmx_int64_t seed, gmx_int64_t step)
731 /* Choose new lambda value, and update transition matrix */
733 int i, ifep, jfep, minfep, maxfep, lamnew, lamtrial, starting_fep_state;
734 real r1, r2, de_old, de_new, de, trialprob, tprob = 0;
736 double *propose, *accept, *remainder;
739 gmx_bool bRestricted;
741 starting_fep_state = fep_state;
742 lamnew = fep_state; /* so that there is a default setting -- stays the same */
744 if (!EWL(expand->elamstats)) /* ignore equilibrating the weights if using WL */
746 if ((expand->lmc_forced_nstart > 0) && (dfhist->n_at_lam[nlim-1] <= expand->lmc_forced_nstart))
748 /* Use a marching method to run through the lambdas and get preliminary free energy data,
749 before starting 'free' sampling. We start free sampling when we have enough at each lambda */
751 /* if we have enough at this lambda, move on to the next one */
753 if (dfhist->n_at_lam[fep_state] == expand->lmc_forced_nstart)
755 lamnew = fep_state+1;
756 if (lamnew == nlim) /* whoops, stepped too far! */
771 snew(remainder, nlim);
773 for (i = 0; i < expand->lmc_repeats; i++)
777 gmx_rng_cycle_2uniform(step, i, seed, RND_SEED_EXPANDED, rnd);
779 for (ifep = 0; ifep < nlim; ifep++)
785 if ((expand->elmcmove == elmcmoveGIBBS) || (expand->elmcmove == elmcmoveMETGIBBS))
788 /* use the Gibbs sampler, with restricted range */
789 if (expand->gibbsdeltalam < 0)
797 minfep = fep_state - expand->gibbsdeltalam;
798 maxfep = fep_state + expand->gibbsdeltalam;
809 GenerateGibbsProbabilities(weighted_lamee, p_k, &pks, minfep, maxfep);
811 if (expand->elmcmove == elmcmoveGIBBS)
813 for (ifep = minfep; ifep <= maxfep; ifep++)
815 propose[ifep] = p_k[ifep];
820 for (lamnew = minfep; lamnew <= maxfep; lamnew++)
822 if (r1 <= p_k[lamnew])
829 else if (expand->elmcmove == elmcmoveMETGIBBS)
832 /* Metropolized Gibbs sampling */
833 for (ifep = minfep; ifep <= maxfep; ifep++)
835 remainder[ifep] = 1 - p_k[ifep];
838 /* find the proposal probabilities */
840 if (remainder[fep_state] == 0)
842 /* only the current state has any probability */
843 /* we have to stay at the current state */
848 for (ifep = minfep; ifep <= maxfep; ifep++)
850 if (ifep != fep_state)
852 propose[ifep] = p_k[ifep]/remainder[fep_state];
861 for (lamtrial = minfep; lamtrial <= maxfep; lamtrial++)
863 pnorm = p_k[lamtrial]/remainder[fep_state];
864 if (lamtrial != fep_state)
874 /* we have now selected lamtrial according to p(lamtrial)/1-p(fep_state) */
876 /* trial probability is min{1,\frac{1 - p(old)}{1-p(new)} MRS 1/8/2008 */
877 trialprob = (remainder[fep_state])/(remainder[lamtrial]);
878 if (trialprob < tprob)
893 /* now figure out the acceptance probability for each */
894 for (ifep = minfep; ifep <= maxfep; ifep++)
897 if (remainder[ifep] != 0)
899 trialprob = (remainder[fep_state])/(remainder[ifep]);
903 trialprob = 1.0; /* this state is the only choice! */
905 if (trialprob < tprob)
909 /* probability for fep_state=0, but that's fine, it's never proposed! */
910 accept[ifep] = tprob;
916 /* it's possible some rounding is failing */
917 if (gmx_within_tol(remainder[fep_state], 0, 50*GMX_DOUBLE_EPS))
919 /* numerical rounding error -- no state other than the original has weight */
924 /* probably not a numerical issue */
926 int nerror = 200+(maxfep-minfep+1)*60;
928 snew(errorstr, nerror);
929 /* if its greater than maxfep, then something went wrong -- probably underflow in the calculation
930 of sum weights. Generated detailed info for failure */
931 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);
932 for (ifep = minfep; ifep <= maxfep; ifep++)
934 loc += sprintf(&errorstr[loc], "%3d %17.10e%17.10e%17.10e\n", ifep, weighted_lamee[ifep], p_k[ifep], dfhist->sum_weights[ifep]);
936 gmx_fatal(FARGS, errorstr);
940 else if ((expand->elmcmove == elmcmoveMETROPOLIS) || (expand->elmcmove == elmcmoveBARKER))
942 /* use the metropolis sampler with trial +/- 1 */
948 lamtrial = fep_state;
952 lamtrial = fep_state-1;
957 if (fep_state == nlim-1)
959 lamtrial = fep_state;
963 lamtrial = fep_state+1;
967 de = weighted_lamee[lamtrial] - weighted_lamee[fep_state];
968 if (expand->elmcmove == elmcmoveMETROPOLIS)
972 if (trialprob < tprob)
976 propose[fep_state] = 0;
977 propose[lamtrial] = 1.0; /* note that this overwrites the above line if fep_state = ntrial, which only occurs at the ends */
978 accept[fep_state] = 1.0; /* doesn't actually matter, never proposed unless fep_state = ntrial, in which case it's 1.0 anyway */
979 accept[lamtrial] = tprob;
982 else if (expand->elmcmove == elmcmoveBARKER)
984 tprob = 1.0/(1.0+exp(-de));
986 propose[fep_state] = (1-tprob);
987 propose[lamtrial] += tprob; /* we add, to account for the fact that at the end, they might be the same point */
988 accept[fep_state] = 1.0;
989 accept[lamtrial] = 1.0;
1003 for (ifep = 0; ifep < nlim; ifep++)
1005 dfhist->Tij[fep_state][ifep] += propose[ifep]*accept[ifep];
1006 dfhist->Tij[fep_state][fep_state] += propose[ifep]*(1.0-accept[ifep]);
1011 dfhist->Tij_empirical[starting_fep_state][lamnew] += 1.0;
1020 /* print out the weights to the log, along with current state */
1021 extern void PrintFreeEnergyInfoToFile(FILE *outfile, t_lambda *fep, t_expanded *expand, t_simtemp *simtemp, df_history_t *dfhist,
1022 int fep_state, int frequency, gmx_int64_t step)
1024 int nlim, i, ifep, jfep;
1025 real dw, dg, dv, dm, Tprint;
1027 const char *print_names[efptNR] = {" FEPL", "MassL", "CoulL", " VdwL", "BondL", "RestT", "Temp.(K)"};
1028 gmx_bool bSimTemp = FALSE;
1030 nlim = fep->n_lambda;
1031 if (simtemp != NULL)
1036 if (mod(step, frequency) == 0)
1038 fprintf(outfile, " MC-lambda information\n");
1039 if (EWL(expand->elamstats) && (!(dfhist->bEquil)))
1041 fprintf(outfile, " Wang-Landau incrementor is: %11.5g\n", dfhist->wl_delta);
1043 fprintf(outfile, " N");
1044 for (i = 0; i < efptNR; i++)
1046 if (fep->separate_dvdl[i])
1048 fprintf(outfile, "%7s", print_names[i]);
1050 else if ((i == efptTEMPERATURE) && bSimTemp)
1052 fprintf(outfile, "%10s", print_names[i]); /* more space for temperature formats */
1055 fprintf(outfile, " Count ");
1056 if (expand->elamstats == elamstatsMINVAR)
1058 fprintf(outfile, "W(in kT) G(in kT) dG(in kT) dV(in kT)\n");
1062 fprintf(outfile, "G(in kT) dG(in kT)\n");
1064 for (ifep = 0; ifep < nlim; ifep++)
1075 dw = dfhist->sum_weights[ifep+1] - dfhist->sum_weights[ifep];
1076 dg = dfhist->sum_dg[ifep+1] - dfhist->sum_dg[ifep];
1077 dv = sqrt(pow(dfhist->sum_variance[ifep+1], 2) - pow(dfhist->sum_variance[ifep], 2));
1078 dm = dfhist->sum_minvar[ifep+1] - dfhist->sum_minvar[ifep];
1081 fprintf(outfile, "%3d", (ifep+1));
1082 for (i = 0; i < efptNR; i++)
1084 if (fep->separate_dvdl[i])
1086 fprintf(outfile, "%7.3f", fep->all_lambda[i][ifep]);
1088 else if (i == efptTEMPERATURE && bSimTemp)
1090 fprintf(outfile, "%9.3f", simtemp->temperatures[ifep]);
1093 if (EWL(expand->elamstats) && (!(dfhist->bEquil))) /* if performing WL and still haven't equilibrated */
1095 if (expand->elamstats == elamstatsWL)
1097 fprintf(outfile, " %8d", (int)dfhist->wl_histo[ifep]);
1101 fprintf(outfile, " %8.3f", dfhist->wl_histo[ifep]);
1104 else /* we have equilibrated weights */
1106 fprintf(outfile, " %8d", dfhist->n_at_lam[ifep]);
1108 if (expand->elamstats == elamstatsMINVAR)
1110 fprintf(outfile, " %10.5f %10.5f %10.5f %10.5f", dfhist->sum_weights[ifep], dfhist->sum_dg[ifep], dg, dv);
1114 fprintf(outfile, " %10.5f %10.5f", dfhist->sum_weights[ifep], dw);
1116 if (ifep == fep_state)
1118 fprintf(outfile, " <<\n");
1122 fprintf(outfile, " \n");
1125 fprintf(outfile, "\n");
1127 if ((mod(step, expand->nstTij) == 0) && (expand->nstTij > 0) && (step > 0))
1129 fprintf(outfile, " Transition Matrix\n");
1130 for (ifep = 0; ifep < nlim; ifep++)
1132 fprintf(outfile, "%12d", (ifep+1));
1134 fprintf(outfile, "\n");
1135 for (ifep = 0; ifep < nlim; ifep++)
1137 for (jfep = 0; jfep < nlim; jfep++)
1139 if (dfhist->n_at_lam[ifep] > 0)
1141 if (expand->bSymmetrizedTMatrix)
1143 Tprint = (dfhist->Tij[ifep][jfep]+dfhist->Tij[jfep][ifep])/(dfhist->n_at_lam[ifep]+dfhist->n_at_lam[jfep]);
1147 Tprint = (dfhist->Tij[ifep][jfep])/(dfhist->n_at_lam[ifep]);
1154 fprintf(outfile, "%12.8f", Tprint);
1156 fprintf(outfile, "%3d\n", (ifep+1));
1159 fprintf(outfile, " Empirical Transition Matrix\n");
1160 for (ifep = 0; ifep < nlim; ifep++)
1162 fprintf(outfile, "%12d", (ifep+1));
1164 fprintf(outfile, "\n");
1165 for (ifep = 0; ifep < nlim; ifep++)
1167 for (jfep = 0; jfep < nlim; jfep++)
1169 if (dfhist->n_at_lam[ifep] > 0)
1171 if (expand->bSymmetrizedTMatrix)
1173 Tprint = (dfhist->Tij_empirical[ifep][jfep]+dfhist->Tij_empirical[jfep][ifep])/(dfhist->n_at_lam[ifep]+dfhist->n_at_lam[jfep]);
1177 Tprint = dfhist->Tij_empirical[ifep][jfep]/(dfhist->n_at_lam[ifep]);
1184 fprintf(outfile, "%12.8f", Tprint);
1186 fprintf(outfile, "%3d\n", (ifep+1));
1192 extern int ExpandedEnsembleDynamics(FILE *log, t_inputrec *ir, gmx_enerdata_t *enerd,
1193 t_state *state, t_extmass *MassQ, int fep_state, df_history_t *dfhist,
1195 rvec *v, t_mdatoms *mdatoms)
1196 /* Note that the state variable is only needed for simulated tempering, not
1197 Hamiltonian expanded ensemble. May be able to remove it after integrator refactoring. */
1199 real *pfep_lamee, *scaled_lamee, *weighted_lamee;
1201 int i, nlim, lamnew, totalsamples;
1202 real oneovert, maxscaled = 0, maxweighted = 0;
1205 double *temperature_lambdas;
1206 gmx_bool bIfReset, bSwitchtoOneOverT, bDoneEquilibrating = FALSE;
1208 expand = ir->expandedvals;
1209 simtemp = ir->simtempvals;
1210 nlim = ir->fepvals->n_lambda;
1212 snew(scaled_lamee, nlim);
1213 snew(weighted_lamee, nlim);
1214 snew(pfep_lamee, nlim);
1217 /* update the count at the current lambda*/
1218 dfhist->n_at_lam[fep_state]++;
1220 /* need to calculate the PV term somewhere, but not needed here? Not until there's a lambda state that's
1221 pressure controlled.*/
1224 where does this PV term go?
1225 for (i=0;i<nlim;i++)
1227 fep_lamee[i] += pVTerm;
1231 /* determine the minimum value to avoid overflow. Probably a better way to do this */
1232 /* we don't need to include the pressure term, since the volume is the same between the two.
1233 is there some term we are neglecting, however? */
1235 if (ir->efep != efepNO)
1237 for (i = 0; i < nlim; i++)
1241 /* Note -- this assumes no mass changes, since kinetic energy is not added . . . */
1242 scaled_lamee[i] = (enerd->enerpart_lambda[i+1]-enerd->enerpart_lambda[0])/(simtemp->temperatures[i]*BOLTZ)
1243 + enerd->term[F_EPOT]*(1.0/(simtemp->temperatures[i])- 1.0/(simtemp->temperatures[fep_state]))/BOLTZ;
1247 scaled_lamee[i] = (enerd->enerpart_lambda[i+1]-enerd->enerpart_lambda[0])/(expand->mc_temp*BOLTZ);
1248 /* mc_temp is currently set to the system reft unless otherwise defined */
1251 /* save these energies for printing, so they don't get overwritten by the next step */
1252 /* they aren't overwritten in the non-free energy case, but we always print with these
1260 for (i = 0; i < nlim; i++)
1262 scaled_lamee[i] = enerd->term[F_EPOT]*(1.0/simtemp->temperatures[i] - 1.0/simtemp->temperatures[fep_state])/BOLTZ;
1267 for (i = 0; i < nlim; i++)
1269 pfep_lamee[i] = scaled_lamee[i];
1271 weighted_lamee[i] = dfhist->sum_weights[i] - scaled_lamee[i];
1274 maxscaled = scaled_lamee[i];
1275 maxweighted = weighted_lamee[i];
1279 if (scaled_lamee[i] > maxscaled)
1281 maxscaled = scaled_lamee[i];
1283 if (weighted_lamee[i] > maxweighted)
1285 maxweighted = weighted_lamee[i];
1290 for (i = 0; i < nlim; i++)
1292 scaled_lamee[i] -= maxscaled;
1293 weighted_lamee[i] -= maxweighted;
1296 /* update weights - we decide whether or not to actually do this inside */
1298 bDoneEquilibrating = UpdateWeights(nlim, expand, dfhist, fep_state, scaled_lamee, weighted_lamee, step);
1299 if (bDoneEquilibrating)
1303 fprintf(log, "\nStep %d: Weights have equilibrated, using criteria: %s\n", (int)step, elmceq_names[expand->elmceq]);
1307 lamnew = ChooseNewLambda(nlim, expand, dfhist, fep_state, weighted_lamee, p_k,
1308 ir->expandedvals->lmc_seed, step);
1309 /* if using simulated tempering, we need to adjust the temperatures */
1310 if (ir->bSimTemp && (lamnew != fep_state)) /* only need to change the temperatures if we change the state */
1315 int nstart, nend, gt;
1317 snew(buf_ngtc, ir->opts.ngtc);
1319 for (i = 0; i < ir->opts.ngtc; i++)
1321 if (ir->opts.ref_t[i] > 0)
1323 told = ir->opts.ref_t[i];
1324 ir->opts.ref_t[i] = simtemp->temperatures[lamnew];
1325 buf_ngtc[i] = sqrt(ir->opts.ref_t[i]/told); /* using the buffer as temperature scaling */
1329 /* we don't need to manipulate the ekind information, as it isn't due to be reset until the next step anyway */
1332 nend = mdatoms->homenr;
1333 for (n = nstart; n < nend; n++)
1338 gt = mdatoms->cTC[n];
1340 for (d = 0; d < DIM; d++)
1342 v[n][d] *= buf_ngtc[gt];
1346 if (IR_NPT_TROTTER(ir) || IR_NPH_TROTTER(ir) || IR_NVT_TROTTER(ir))
1348 /* we need to recalculate the masses if the temperature has changed */
1349 init_npt_masses(ir, state, MassQ, FALSE);
1350 for (i = 0; i < state->nnhpres; i++)
1352 for (j = 0; j < ir->opts.nhchainlength; j++)
1354 state->nhpres_vxi[i+j] *= buf_ngtc[i];
1357 for (i = 0; i < ir->opts.ngtc; i++)
1359 for (j = 0; j < ir->opts.nhchainlength; j++)
1361 state->nosehoover_vxi[i+j] *= buf_ngtc[i];
1368 /* now check on the Wang-Landau updating critera */
1370 if (EWL(expand->elamstats))
1372 bSwitchtoOneOverT = FALSE;
1373 if (expand->bWLoneovert)
1376 for (i = 0; i < nlim; i++)
1378 totalsamples += dfhist->n_at_lam[i];
1380 oneovert = (1.0*nlim)/totalsamples;
1381 /* oneovert has decreasd by a bit since last time, so we actually make sure its within one of this number */
1382 /* switch to 1/t incrementing when wl_delta has decreased at least once, and wl_delta is now less than 1/t */
1383 if ((dfhist->wl_delta <= ((totalsamples)/(totalsamples-1.00001))*oneovert) &&
1384 (dfhist->wl_delta < expand->init_wl_delta))
1386 bSwitchtoOneOverT = TRUE;
1389 if (bSwitchtoOneOverT)
1391 dfhist->wl_delta = oneovert; /* now we reduce by this each time, instead of only at flatness */
1395 bIfReset = CheckHistogramRatios(nlim, dfhist->wl_histo, expand->wl_ratio);
1398 for (i = 0; i < nlim; i++)
1400 dfhist->wl_histo[i] = 0;
1402 dfhist->wl_delta *= expand->wl_scale;
1405 fprintf(log, "\nStep %d: weights are now:", (int)step);
1406 for (i = 0; i < nlim; i++)
1408 fprintf(log, " %.5f", dfhist->sum_weights[i]);
1416 sfree(scaled_lamee);
1417 sfree(weighted_lamee);