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57 #include "gmx_statistics.h"
65 #define FACTOR 1000.0 /* Convert nm^2/ps to 10e-5 cm^2/s */
66 /* NORMAL = total diffusion coefficient (default). X,Y,Z is diffusion
67 coefficient in X,Y,Z direction. LATERAL is diffusion coefficient in
68 plane perpendicular to axis
70 typedef enum { NOT_USED, NORMAL, X, Y, Z, LATERAL } msd_type;
73 real t0; /* start time and time increment between */
74 real delta_t; /* time between restart points */
75 real beginfit, /* the begin/end time for fits as reals between */
77 real dim_factor; /* the dimensionality factor for the diffusion
79 real **data; /* the displacement data. First index is the group
80 number, second is frame number */
81 real *time; /* frame time */
82 real *mass; /* masses for mass-weighted msd */
84 rvec **x0; /* original positions */
85 rvec *com; /* center of mass correction for each frame */
86 gmx_stats_t **lsq; /* fitting stats for individual molecule msds */
87 msd_type type; /* the type of msd to calculate (lateral, etc.)*/
88 int axis; /* the axis along which to calculate */
90 int nrestart; /* number of restart points */
91 int nmol; /* number of molecules (for bMol) */
92 int nframes; /* number of frames */
94 int ngrp; /* number of groups to use for msd calculation */
96 int **ndata; /* the number of msds (particles/mols) per data
100 typedef real t_calc_func(t_corr *,int,atom_id[],int,rvec[],rvec,gmx_bool,matrix,
101 const output_env_t oenv);
103 static real thistime(t_corr *curr)
105 return curr->time[curr->nframes];
108 static gmx_bool in_data(t_corr *curr,int nx00)
110 return curr->nframes-curr->n_offs[nx00];
113 t_corr *init_corr(int nrgrp,int type,int axis,real dim_factor,
114 int nmol,gmx_bool bTen,gmx_bool bMass,real dt,t_topology *top,
115 real beginfit,real endfit)
122 curr->type = (msd_type)type;
127 curr->beginfit = (1 - 2*GMX_REAL_EPS)*beginfit;
128 curr->endfit = (1 + 2*GMX_REAL_EPS)*endfit;
133 curr->dim_factor = dim_factor;
135 snew(curr->ndata,nrgrp);
136 snew(curr->data,nrgrp);
138 snew(curr->datam,nrgrp);
139 for(i=0; (i<nrgrp); i++) {
140 curr->ndata[i] = NULL;
141 curr->data[i] = NULL;
143 curr->datam[i] = NULL;
148 if (curr->nmol > 0) {
149 snew(curr->mass,curr->nmol);
150 for(i=0; i<curr->nmol; i++)
156 snew(curr->mass,atoms->nr);
157 for(i=0; (i<atoms->nr); i++) {
158 curr->mass[i] = atoms->atom[i].m;
166 static void corr_print(t_corr *curr,gmx_bool bTen,const char *fn,const char *title,
168 real msdtime,real beginfit,real endfit,
169 real *DD,real *SigmaD,char *grpname[],
170 const output_env_t oenv)
175 out=xvgropen(fn,title,output_env_get_xvgr_tlabel(oenv),yaxis,oenv);
177 fprintf(out,"# MSD gathered over %g %s with %d restarts\n",
178 msdtime,output_env_get_time_unit(oenv),curr->nrestart);
179 fprintf(out,"# Diffusion constants fitted from time %g to %g %s\n",
180 beginfit,endfit,output_env_get_time_unit(oenv));
181 for(i=0; i<curr->ngrp; i++)
182 fprintf(out,"# D[%10s] = %.4f (+/- %.4f) (1e-5 cm^2/s)\n",
183 grpname[i],DD[i],SigmaD[i]);
185 for(i=0; i<curr->nframes; i++) {
186 fprintf(out,"%10g",output_env_conv_time(oenv,curr->time[i]));
187 for(j=0; j<curr->ngrp; j++) {
188 fprintf(out," %10g",curr->data[j][i]);
190 fprintf(out," %10g %10g %10g %10g %10g %10g",
191 curr->datam[j][i][XX][XX],
192 curr->datam[j][i][YY][YY],
193 curr->datam[j][i][ZZ][ZZ],
194 curr->datam[j][i][YY][XX],
195 curr->datam[j][i][ZZ][XX],
196 curr->datam[j][i][ZZ][YY]);
204 /* called from corr_loop, to do the main calculations */
205 static void calc_corr(t_corr *curr,int nr,int nx,atom_id index[],rvec xc[],
206 gmx_bool bRmCOMM,rvec com,t_calc_func *calc1,gmx_bool bTen,
207 const output_env_t oenv)
214 /* Check for new starting point */
215 if (curr->nlast < curr->nrestart) {
216 if ((thistime(curr) >= (curr->nlast*curr->delta_t)) && (nr==0)) {
217 memcpy(curr->x0[curr->nlast],xc,curr->ncoords*sizeof(xc[0]));
218 curr->n_offs[curr->nlast]=curr->nframes;
219 copy_rvec(com,curr->com[curr->nlast]);
224 /* nx0 appears to be the number of new starting points,
225 * so for all starting points, call calc1.
227 for(nx0=0; (nx0<curr->nlast); nx0++) {
229 rvec_sub(com,curr->com[nx0],dcom);
233 g = calc1(curr,nx,index,nx0,xc,dcom,bTen,mat,oenv);
235 printf("g[%d]=%g\n",nx0,g);
237 curr->data[nr][in_data(curr,nx0)] += g;
239 m_add(curr->datam[nr][in_data(curr,nx0)],mat,
240 curr->datam[nr][in_data(curr,nx0)]);
242 curr->ndata[nr][in_data(curr,nx0)]++;
246 /* the non-mass-weighted mean-squared displacement calcuation */
247 static real calc1_norm(t_corr *curr,int nx,atom_id index[],int nx0,rvec xc[],
248 rvec dcom,gmx_bool bTen,matrix mat, const output_env_t oenv)
257 for(i=0; (i<nx); i++) {
260 switch (curr->type) {
262 for(m=0; (m<DIM); m++) {
263 rv[m] = xc[ix][m] - curr->x0[nx0][ix][m] - dcom[m];
266 for(m2=0; m2<=m; m2++)
267 mat[m][m2] += rv[m]*rv[m2];
274 r = xc[ix][curr->type-X] - curr->x0[nx0][ix][curr->type-X] -
279 for(m=0; (m<DIM); m++) {
280 if (m != curr->axis) {
281 r = xc[ix][m] - curr->x0[nx0][ix][m] - dcom[m];
287 gmx_fatal(FARGS,"Error: did not expect option value %d",curr->type);
292 msmul(mat,1.0/nx,mat);
297 /* calculate the com of molecules in x and put it into xa */
298 static void calc_mol_com(int nmol,int *molindex,t_block *mols,t_atoms *atoms,
305 for(m=0; m<nmol; m++) {
309 for(i=mols->index[mol]; i<mols->index[mol+1]; i++) {
310 mass = atoms->atom[i].m;
312 xm[d] += mass*x[i][d];
315 svmul(1/mtot,xm,xa[m]);
319 static real calc_one_mw(t_corr *curr,int ix,int nx0,rvec xc[],real *tm,
320 rvec dcom,gmx_bool bTen,matrix mat)
331 switch (curr->type) {
333 for(m=0; (m<DIM); m++) {
334 rv[m] = xc[ix][m] - curr->x0[nx0][ix][m] - dcom[m];
335 r2 += mm*rv[m]*rv[m];
337 for(m2=0; m2<=m; m2++)
338 mat[m][m2] += mm*rv[m]*rv[m2];
345 r = xc[ix][curr->type-X] - curr->x0[nx0][ix][curr->type-X] -
350 for(m=0; (m<DIM); m++) {
351 if (m != curr->axis) {
352 r = xc[ix][m] - curr->x0[nx0][ix][m] - dcom[m];
358 gmx_fatal(FARGS,"Options got screwed. Did not expect value %d\n",curr->type);
363 /* the normal, mass-weighted mean-squared displacement calcuation */
364 static real calc1_mw(t_corr *curr,int nx,atom_id index[],int nx0,rvec xc[],
365 rvec dcom,gmx_bool bTen,matrix mat,const output_env_t oenv)
372 for(i=0; (i<nx); i++)
373 g += calc_one_mw(curr,index[i],nx0,xc,&tm,dcom,bTen,mat);
382 /* prepare the coordinates by removing periodic boundary crossings.
383 gnx = the number of atoms/molecules
385 xcur = the current coordinates
386 xprev = the previous coordinates
387 box = the box matrix */
388 static void prep_data(gmx_bool bMol,int gnx,atom_id index[],
389 rvec xcur[],rvec xprev[],matrix box)
394 /* Remove periodicity */
395 for(m=0; (m<DIM); m++)
396 hbox[m]=0.5*box[m][m];
398 for(i=0; (i<gnx); i++) {
404 for(m=DIM-1; m>=0; m--)
410 while(xcur[ind][m]-xprev[ind][m] <= -hbox[m])
411 rvec_inc(xcur[ind],box[m]);
412 while(xcur[ind][m]-xprev[ind][m] > hbox[m])
413 rvec_dec(xcur[ind],box[m]);
418 /* calculate the center of mass for a group
419 gnx = the number of atoms/molecules
421 xcur = the current coordinates
422 xprev = the previous coordinates
424 atoms = atom data (for mass)
425 com(output) = center of mass */
426 static void calc_com(gmx_bool bMol, int gnx, atom_id index[],
427 rvec xcur[],rvec xprev[],matrix box, t_atoms *atoms,
439 prep_data(bMol, gnx, index, xcur, xprev, box);
440 for(i=0; (i<gnx); i++)
448 mass = atoms->atom[ind].m;
450 sx[m] += mass*xcur[ind][m];
454 com[m] = sx[m]/tmass;
458 static real calc1_mol(t_corr *curr,int nx,atom_id index[],int nx0,rvec xc[],
459 rvec dcom,gmx_bool bTen,matrix mat, const output_env_t oenv)
464 tt = curr->time[in_data(curr,nx0)];
468 for(i=0; (i<nx); i++) {
469 g = calc_one_mw(curr,i,nx0,xc,&tm,dcom,bTen,mat);
470 /* We don't need to normalize as the mass was set to 1 */
472 if (tt >= curr->beginfit && (curr->endfit < 0 || tt <= curr->endfit))
473 gmx_stats_add_point(curr->lsq[nx0][i],tt,g,0,0);
475 msmul(mat,1.0/nx,mat);
480 void printmol(t_corr *curr,const char *fn,
481 const char *fn_pdb,int *molindex,t_topology *top,
482 rvec *x,int ePBC,matrix box, const output_env_t oenv)
488 real a,b,D,Dav,D2av,VarD,sqrtD,sqrtD_max,scale;
489 t_pdbinfo *pdbinfo=NULL;
492 out=xvgropen(fn,"Diffusion Coefficients / Molecule","Molecule","D",oenv);
495 if (top->atoms.pdbinfo == NULL)
496 snew(top->atoms.pdbinfo,top->atoms.nr);
497 pdbinfo = top->atoms.pdbinfo;
498 mol2a = top->mols.index;
503 for(i=0; (i<curr->nmol); i++) {
504 lsq1 = gmx_stats_init();
505 for(j=0; (j<curr->nrestart); j++) {
508 while(gmx_stats_get_point(curr->lsq[j][i],&xx,&yy,&dx,&dy) == estatsOK)
509 gmx_stats_add_point(lsq1,xx,yy,dx,dy);
511 gmx_stats_get_ab(lsq1,elsqWEIGHT_NONE,&a,&b,NULL,NULL,NULL,NULL);
512 gmx_stats_done(lsq1);
514 D = a*FACTOR/curr->dim_factor;
519 fprintf(out,"%10d %10g\n",i,D);
522 if (sqrtD > sqrtD_max)
524 for(j=mol2a[molindex[i]]; j<mol2a[molindex[i]+1]; j++)
525 pdbinfo[j].bfac = sqrtD;
529 do_view(oenv,fn,"-graphtype bar");
531 /* Compute variance, stddev and error */
534 VarD = D2av - sqr(Dav);
535 printf("<D> = %.4f Std. Dev. = %.4f Error = %.4f\n",
536 Dav,sqrt(VarD),sqrt(VarD/curr->nmol));
540 while (scale*sqrtD_max > 10)
542 while (scale*sqrtD_max < 0.1)
544 for(i=0; i<top->atoms.nr; i++)
545 pdbinfo[i].bfac *= scale;
546 write_sto_conf(fn_pdb,"molecular MSD",&top->atoms,x,NULL,ePBC,box);
550 /* this is the main loop for the correlation type functions
551 * fx and nx are file pointers to things like read_first_x and
554 int corr_loop(t_corr *curr,const char *fn,t_topology *top,int ePBC,
555 gmx_bool bMol,int gnx[],atom_id *index[],
556 t_calc_func *calc1,gmx_bool bTen, int *gnx_com, atom_id *index_com[],
557 real dt, real t_pdb,rvec **x_pdb,matrix box_pdb,
558 const output_env_t oenv)
560 rvec *x[2]; /* the coordinates to read */
561 rvec *xa[2]; /* the coordinates to calculate displacements for */
564 int natoms,i,j,cur=0,maxframes=0;
569 gmx_rmpbc_t gpbc=NULL;
571 natoms = read_first_x(oenv,&status,fn,&curr->t0,&(x[cur]),box);
573 fprintf(stderr,"Read %d atoms for first frame\n",natoms);
575 if ((gnx_com!=NULL) && natoms < top->atoms.nr) {
576 fprintf(stderr,"WARNING: The trajectory only contains part of the system (%d of %d atoms) and therefore the COM motion of only this part of the system will be removed\n",natoms,top->atoms.nr);
579 snew(x[prev],natoms);
582 curr->ncoords = curr->nmol;
583 snew(xa[0],curr->ncoords);
584 snew(xa[1],curr->ncoords);
586 curr->ncoords = natoms;
597 gpbc = gmx_rmpbc_init(&top->idef,ePBC,natoms,box);
599 /* the loop over all frames */
602 if (x_pdb && ((bFirst && t_pdb < t) ||
604 t_pdb > t - 0.5*(t - t_prev) &&
605 t_pdb < t + 0.5*(t - t_prev))))
609 for(i=0; i<natoms; i++)
610 copy_rvec(x[cur][i],(*x_pdb)[i]);
611 copy_mat(box,box_pdb);
615 /* check whether we've reached a restart point */
616 if (bRmod(t,curr->t0,dt)) {
619 srenew(curr->x0,curr->nrestart);
620 snew(curr->x0[curr->nrestart-1],curr->ncoords);
621 srenew(curr->com,curr->nrestart);
622 srenew(curr->n_offs,curr->nrestart);
623 srenew(curr->lsq,curr->nrestart);
624 snew(curr->lsq[curr->nrestart-1],curr->nmol);
625 for(i=0;i<curr->nmol;i++)
626 curr->lsq[curr->nrestart-1][i] = gmx_stats_init();
629 fprintf(debug,"Extended data structures because of new restart %d\n",
632 /* create or extend the frame-based arrays */
633 if (curr->nframes >= maxframes-1) {
635 for(i=0; (i<curr->ngrp); i++) {
636 curr->ndata[i] = NULL;
637 curr->data[i] = NULL;
639 curr->datam[i] = NULL;
644 for(i=0; (i<curr->ngrp); i++) {
645 srenew(curr->ndata[i],maxframes);
646 srenew(curr->data[i],maxframes);
648 srenew(curr->datam[i],maxframes);
649 for(j=maxframes-10; j<maxframes; j++) {
653 clear_mat(curr->datam[i][j]);
656 srenew(curr->time,maxframes);
660 curr->time[curr->nframes] = t - curr->t0;
662 /* for the first frame, the previous frame is a copy of the first frame */
664 memcpy(xa[prev],xa[cur],curr->ncoords*sizeof(xa[prev][0]));
668 /* make the molecules whole */
670 gmx_rmpbc(gpbc,natoms,box,x[cur]);
672 /* calculate the molecules' centers of masses and put them into xa */
674 calc_mol_com(gnx[0],index[0],&top->mols,&top->atoms, x[cur],xa[cur]);
676 /* first remove the periodic boundary condition crossings */
677 for(i=0;i<curr->ngrp;i++)
679 prep_data(bMol, gnx[i], index[i], xa[cur], xa[prev], box);
682 /* calculate the center of mass */
685 prep_data(bMol, gnx_com[0], index_com[0], xa[cur], xa[prev], box);
686 calc_com(bMol, gnx_com[0], index_com[0], xa[cur], xa[prev], box,
690 /* loop over all groups in index file */
691 for(i=0; (i<curr->ngrp); i++)
693 /* calculate something useful, like mean square displacements */
694 calc_corr(curr,i,gnx[i],index[i],xa[cur], (gnx_com!=NULL),com,
701 } while (read_next_x(oenv,status,&t,natoms,x[cur],box));
702 fprintf(stderr,"\nUsed %d restart points spaced %g %s over %g %s\n\n",
704 output_env_conv_time(oenv,dt), output_env_get_time_unit(oenv),
705 output_env_conv_time(oenv,curr->time[curr->nframes-1]),
706 output_env_get_time_unit(oenv) );
709 gmx_rmpbc_done(gpbc);
716 static void index_atom2mol(int *n,int *index,t_block *mols)
718 int nat,i,nmol,mol,j;
725 while (index[i] > mols->index[mol]) {
728 gmx_fatal(FARGS,"Atom index out of range: %d",index[i]+1);
730 for(j=mols->index[mol]; j<mols->index[mol+1]; j++) {
731 if (i >= nat || index[i] != j)
732 gmx_fatal(FARGS,"The index group does not consist of whole molecules");
738 fprintf(stderr,"Split group of %d atoms into %d molecules\n",nat,nmol);
743 void do_corr(const char *trx_file, const char *ndx_file, const char *msd_file,
744 const char *mol_file, const char *pdb_file,real t_pdb,
745 int nrgrp, t_topology *top,int ePBC,
746 gmx_bool bTen,gmx_bool bMW,gmx_bool bRmCOMM,
747 int type,real dim_factor,int axis,
748 real dt,real beginfit,real endfit,const output_env_t oenv)
751 int *gnx; /* the selected groups' sizes */
752 atom_id **index; /* selected groups' indices */
754 int i,i0,i1,j,N,nat_trx;
755 real *DD,*SigmaD,a,a2,b,r,chi2;
758 int *gnx_com=NULL; /* the COM removal group size */
759 atom_id **index_com=NULL; /* the COM removal group atom indices */
760 char **grpname_com=NULL; /* the COM removal group name */
766 fprintf(stderr, "\nSelect a group to calculate mean squared displacement for:\n");
767 get_index(&top->atoms,ndx_file,nrgrp,gnx,index,grpname);
775 fprintf(stderr, "\nNow select a group for center of mass removal:\n");
776 get_index(&top->atoms, ndx_file, 1, gnx_com, index_com, grpname_com);
780 index_atom2mol(&gnx[0],index[0],&top->mols);
782 msd = init_corr(nrgrp,type,axis,dim_factor,
783 mol_file==NULL ? 0 : gnx[0],bTen,bMW,dt,top,
787 corr_loop(msd,trx_file,top,ePBC,mol_file ? gnx[0] : 0,gnx,index,
788 (mol_file!=NULL) ? calc1_mol : (bMW ? calc1_mw : calc1_norm),
789 bTen, gnx_com, index_com, dt,t_pdb,
790 pdb_file ? &x : NULL,box,oenv);
792 /* Correct for the number of points */
793 for(j=0; (j<msd->ngrp); j++) {
794 for(i=0; (i<msd->nframes); i++) {
795 msd->data[j][i] /= msd->ndata[j][i];
797 msmul(msd->datam[j][i],1.0/msd->ndata[j][i],msd->datam[j][i]);
802 if (pdb_file && x == NULL) {
803 fprintf(stderr,"\nNo frame found need time tpdb = %g ps\n"
804 "Can not write %s\n\n",t_pdb,pdb_file);
807 top->atoms.nr = nat_trx;
808 printmol(msd,mol_file,pdb_file,index[0],top,x,ePBC,box,oenv);
815 if (beginfit == -1) {
816 i0 = (int)(0.1*(msd->nframes - 1) + 0.5);
817 beginfit = msd->time[i0];
819 for(i0=0; i0<msd->nframes && msd->time[i0]<beginfit; i0++)
823 i1 = (int)(0.9*(msd->nframes - 1) + 0.5) + 1;
824 endfit = msd->time[i1-1];
826 for(i1=i0; i1<msd->nframes && msd->time[i1]<=endfit; i1++)
828 fprintf(stdout,"Fitting from %g to %g %s\n\n",beginfit,endfit,
829 output_env_get_time_unit(oenv));
833 fprintf(stdout,"Not enough points for fitting (%d).\n"
834 "Can not determine the diffusion constant.\n",N);
837 snew(SigmaD,msd->ngrp);
838 for(j=0; j<msd->ngrp; j++) {
840 lsq_y_ax_b(N/2,&(msd->time[i0]),&(msd->data[j][i0]),&a,&b,&r,&chi2);
841 lsq_y_ax_b(N/2,&(msd->time[i0+N/2]),&(msd->data[j][i0+N/2]),&a2,&b,&r,&chi2);
842 SigmaD[j] = fabs(a-a2);
845 lsq_y_ax_b(N,&(msd->time[i0]),&(msd->data[j][i0]),&(DD[j]),&b,&r,&chi2);
846 DD[j] *= FACTOR/msd->dim_factor;
847 SigmaD[j] *= FACTOR/msd->dim_factor;
848 if (DD[j] > 0.01 && DD[j] < 1e4)
849 fprintf(stdout,"D[%10s] %.4f (+/- %.4f) 1e-5 cm^2/s\n",
850 grpname[j],DD[j],SigmaD[j]);
852 fprintf(stdout,"D[%10s] %.4g (+/- %.4g) 1e-5 cm^2/s\n",
853 grpname[j],DD[j], SigmaD[j]);
856 /* Print mean square displacement */
857 corr_print(msd,bTen,msd_file,
858 "Mean Square Displacement",
860 msd->time[msd->nframes-1],beginfit,endfit,DD,SigmaD,grpname,oenv);
863 int gmx_msd(int argc,char *argv[])
865 const char *desc[] = {
866 "[TT]g_msd[tt] computes the mean square displacement (MSD) of atoms from",
867 "a set of initial positions. This provides an easy way to compute",
868 "the diffusion constant using the Einstein relation.",
869 "The time between the reference points for the MSD calculation",
870 "is set with [TT]-trestart[tt].",
871 "The diffusion constant is calculated by least squares fitting a",
872 "straight line (D*t + c) through the MSD(t) from [TT]-beginfit[tt] to",
873 "[TT]-endfit[tt] (note that t is time from the reference positions,",
874 "not simulation time). An error estimate given, which is the difference",
875 "of the diffusion coefficients obtained from fits over the two halves",
876 "of the fit interval.[PAR]",
877 "There are three, mutually exclusive, options to determine different",
878 "types of mean square displacement: [TT]-type[tt], [TT]-lateral[tt]",
879 "and [TT]-ten[tt]. Option [TT]-ten[tt] writes the full MSD tensor for",
880 "each group, the order in the output is: trace xx yy zz yx zx zy.[PAR]",
881 "If [TT]-mol[tt] is set, [TT]g_msd[tt] plots the MSD for individual molecules",
882 "(including making molecules whole across periodic boundaries): ",
883 "for each individual molecule a diffusion constant is computed for ",
884 "its center of mass. The chosen index group will be split into ",
886 "The default way to calculate a MSD is by using mass-weighted averages.",
887 "This can be turned off with [TT]-nomw[tt].[PAR]",
888 "With the option [TT]-rmcomm[tt], the center of mass motion of a ",
889 "specific group can be removed. For trajectories produced with ",
890 "GROMACS this is usually not necessary, ",
891 "as [TT]mdrun[tt] usually already removes the center of mass motion.",
892 "When you use this option be sure that the whole system is stored",
893 "in the trajectory file.[PAR]",
894 "The diffusion coefficient is determined by linear regression of the MSD,",
895 "where, unlike for the normal output of D, the times are weighted",
896 "according to the number of reference points, i.e. short times have",
897 "a higher weight. Also when [TT]-beginfit[tt]=-1,fitting starts at 10%",
898 "and when [TT]-endfit[tt]=-1, fitting goes to 90%.",
899 "Using this option one also gets an accurate error estimate",
900 "based on the statistics between individual molecules.",
901 "Note that this diffusion coefficient and error estimate are only",
902 "accurate when the MSD is completely linear between",
903 "[TT]-beginfit[tt] and [TT]-endfit[tt].[PAR]",
904 "Option [TT]-pdb[tt] writes a [TT].pdb[tt] file with the coordinates of the frame",
905 "at time [TT]-tpdb[tt] with in the B-factor field the square root of",
906 "the diffusion coefficient of the molecule.",
907 "This option implies option [TT]-mol[tt]."
909 static const char *normtype[]= { NULL,"no","x","y","z",NULL };
910 static const char *axtitle[] = { NULL,"no","x","y","z",NULL };
911 static int ngroup = 1;
913 static real t_pdb = 0;
914 static real beginfit = -1;
915 static real endfit = -1;
916 static gmx_bool bTen = FALSE;
917 static gmx_bool bMW = TRUE;
918 static gmx_bool bRmCOMM = FALSE;
920 { "-type", FALSE, etENUM, {normtype},
921 "Compute diffusion coefficient in one direction" },
922 { "-lateral", FALSE, etENUM, {axtitle},
923 "Calculate the lateral diffusion in a plane perpendicular to" },
924 { "-ten", FALSE, etBOOL, {&bTen},
925 "Calculate the full tensor" },
926 { "-ngroup", FALSE, etINT, {&ngroup},
927 "Number of groups to calculate MSD for" },
928 { "-mw", FALSE, etBOOL, {&bMW},
929 "Mass weighted MSD" },
930 { "-rmcomm", FALSE, etBOOL, {&bRmCOMM},
931 "Remove center of mass motion" },
932 { "-tpdb",FALSE, etTIME, {&t_pdb},
933 "The frame to use for option [TT]-pdb[tt] (%t)" },
934 { "-trestart",FALSE, etTIME, {&dt},
935 "Time between restarting points in trajectory (%t)" },
936 { "-beginfit",FALSE, etTIME, {&beginfit},
937 "Start time for fitting the MSD (%t), -1 is 10%" },
938 { "-endfit",FALSE, etTIME, {&endfit},
939 "End time for fitting the MSD (%t), -1 is 90%" }
943 { efTRX, NULL, NULL, ffREAD },
944 { efTPS, NULL, NULL, ffREAD },
945 { efNDX, NULL, NULL, ffOPTRD },
946 { efXVG, NULL, "msd", ffWRITE },
947 { efXVG, "-mol", "diff_mol",ffOPTWR },
948 { efPDB, "-pdb", "diff_mol", ffOPTWR }
950 #define NFILE asize(fnm)
956 const char *trx_file, *tps_file, *ndx_file, *msd_file, *mol_file, *pdb_file;
963 CopyRight(stderr,argv[0]);
965 parse_common_args(&argc,argv,
966 PCA_CAN_VIEW | PCA_CAN_BEGIN | PCA_CAN_END | PCA_TIME_UNIT | PCA_BE_NICE,
967 NFILE,fnm,asize(pa),pa,asize(desc),desc,0,NULL,&oenv);
968 trx_file = ftp2fn_null(efTRX,NFILE,fnm);
969 tps_file = ftp2fn_null(efTPS,NFILE,fnm);
970 ndx_file = ftp2fn_null(efNDX,NFILE,fnm);
971 msd_file = ftp2fn_null(efXVG,NFILE,fnm);
972 pdb_file = opt2fn_null("-pdb",NFILE,fnm);
974 mol_file = opt2fn("-mol",NFILE,fnm);
976 mol_file = opt2fn_null("-mol",NFILE,fnm);
979 gmx_fatal(FARGS,"Must have at least 1 group (now %d)",ngroup);
980 if (mol_file && ngroup > 1)
981 gmx_fatal(FARGS,"With molecular msd can only have 1 group (now %d)",
987 fprintf(stderr,"Calculating diffusion coefficients for molecules.\n");
990 if (normtype[0][0]!='n') {
991 type = normtype[0][0] - 'x' + X; /* See defines above */
998 if ((type==NORMAL) && (axtitle[0][0]!='n')) {
1001 axis = (axtitle[0][0] - 'x'); /* See defines above */
1006 if (bTen && type != NORMAL)
1007 gmx_fatal(FARGS,"Can only calculate the full tensor for 3D msd");
1009 bTop = read_tps_conf(tps_file,title,&top,&ePBC,&xdum,NULL,box,bMW||bRmCOMM);
1010 if (mol_file && !bTop)
1012 "Could not read a topology from %s. Try a tpr file instead.",
1015 do_corr(trx_file,ndx_file,msd_file,mol_file,pdb_file,t_pdb,ngroup,
1016 &top,ePBC,bTen,bMW,bRmCOMM,type,dim_factor,axis,dt,beginfit,endfit,
1019 view_all(oenv,NFILE, fnm);