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60 int gmx_vanhove(int argc,char *argv[])
62 const char *desc[] = {
63 "[TT]g_vanhove[tt] computes the Van Hove correlation function.",
64 "The Van Hove G(r,t) is the probability that a particle that is at r[SUB]0[sub]",
65 "at time zero can be found at position r[SUB]0[sub]+r at time t.",
66 "[TT]g_vanhove[tt] determines G not for a vector r, but for the length of r.",
67 "Thus it gives the probability that a particle moves a distance of r",
69 "Jumps across the periodic boundaries are removed.",
70 "Corrections are made for scaling due to isotropic",
71 "or anisotropic pressure coupling.",
73 "With option [TT]-om[tt] the whole matrix can be written as a function",
74 "of t and r or as a function of [SQRT]t[sqrt] and r (option [TT]-sqrt[tt]).",
76 "With option [TT]-or[tt] the Van Hove function is plotted for one",
77 "or more values of t. Option [TT]-nr[tt] sets the number of times,",
78 "option [TT]-fr[tt] the number spacing between the times.",
79 "The binwidth is set with option [TT]-rbin[tt]. The number of bins",
80 "is determined automatically.",
82 "With option [TT]-ot[tt] the integral up to a certain distance",
83 "(option [TT]-rt[tt]) is plotted as a function of time.",
85 "For all frames that are read the coordinates of the selected particles",
86 "are stored in memory. Therefore the program may use a lot of memory.",
87 "For options [TT]-om[tt] and [TT]-ot[tt] the program may be slow.",
88 "This is because the calculation scales as the number of frames times",
89 "[TT]-fm[tt] or [TT]-ft[tt].",
90 "Note that with the [TT]-dt[tt] option the memory usage and calculation",
91 "time can be reduced."
93 static int fmmax=0,ftmax=0,nlev=81,nr=1,fshift=0;
94 static real sbin=0,rmax=2,rbin=0.01,mmax=0,rint=0;
96 { "-sqrt", FALSE, etREAL,{&sbin},
97 "Use [SQRT]t[sqrt] on the matrix axis which binspacing # in [SQRT]ps[sqrt]" },
98 { "-fm", FALSE, etINT, {&fmmax},
99 "Number of frames in the matrix, 0 is plot all" },
100 { "-rmax", FALSE, etREAL, {&rmax},
101 "Maximum r in the matrix (nm)" },
102 { "-rbin", FALSE, etREAL, {&rbin},
103 "Binwidth in the matrix and for [TT]-or[tt] (nm)" },
104 { "-mmax", FALSE, etREAL, {&mmax},
105 "Maximum density in the matrix, 0 is calculate (1/nm)" },
106 { "-nlevels" ,FALSE, etINT, {&nlev},
107 "Number of levels in the matrix" },
108 { "-nr", FALSE, etINT, {&nr},
109 "Number of curves for the [TT]-or[tt] output" },
110 { "-fr", FALSE, etINT, {&fshift},
111 "Frame spacing for the [TT]-or[tt] output" },
112 { "-rt", FALSE, etREAL, {&rint},
113 "Integration limit for the [TT]-ot[tt] output (nm)" },
114 { "-ft", FALSE, etINT, {&ftmax},
115 "Number of frames in the [TT]-ot[tt] output, 0 is plot all" }
117 #define NPA asize(pa)
120 { efTRX, NULL, NULL, ffREAD },
121 { efTPS, NULL, NULL, ffREAD },
122 { efNDX, NULL, NULL, ffOPTRD },
123 { efXPM, "-om", "vanhove", ffOPTWR },
124 { efXVG, "-or", "vanhove_r", ffOPTWR },
125 { efXVG, "-ot", "vanhove_t", ffOPTWR }
127 #define NFILE asize(fnm)
130 const char *matfile,*otfile,*orfile;
134 matrix boxtop,box,*sbox,avbox,corr;
136 int isize,nalloc,nallocn,natom;
140 int nfr,f,ff,i,m,mat_nx=0,nbin=0,bin,mbin,fbin;
141 real *time,t,invbin=0,rmax2=0,rint2=0,d2;
142 real invsbin=0,matmax,normfac,dt,*tickx,*ticky;
143 char buf[STRLEN],**legend;
145 int *pt=NULL,**pr=NULL,*mcount=NULL,*tcount=NULL,*rcount=NULL;
147 t_rgb rlo={1,1,1}, rhi={0,0,0};
149 CopyRight(stderr,argv[0]);
151 parse_common_args(&argc,argv,PCA_CAN_VIEW | PCA_CAN_TIME | PCA_BE_NICE,
152 NFILE,fnm,asize(pa),pa,asize(desc),desc,0,NULL,&oenv);
154 matfile = opt2fn_null("-om",NFILE,fnm);
155 if (opt2parg_bSet("-fr",NPA,pa))
156 orfile = opt2fn("-or",NFILE,fnm);
158 orfile = opt2fn_null("-or",NFILE,fnm);
159 if (opt2parg_bSet("-rt",NPA,pa))
160 otfile = opt2fn("-ot",NFILE,fnm);
162 otfile = opt2fn_null("-ot",NFILE,fnm);
164 if (!matfile && !otfile && !orfile) {
166 "For output set one (or more) of the output file options\n");
170 read_tps_conf(ftp2fn(efTPS,NFILE,fnm),title,&top,&ePBC,&xtop,NULL,boxtop,
172 get_index(&top.atoms,ftp2fn_null(efNDX,NFILE,fnm),1,&isize,&index,&grpname);
180 natom=read_first_x(oenv,&status,ftp2fn(efTRX,NFILE,fnm),&t,&x,box);
191 copy_mat(box,sbox[nfr]);
192 /* This assumes that the off-diagonal box elements
193 * are not affected by jumps across the periodic boundaries.
195 m_add(avbox,box,avbox);
197 for(i=0; i<isize; i++)
198 copy_rvec(x[index[i]],sx[nfr][i]);
201 } while (read_next_x(oenv,status,&t,natom,x,box));
207 fprintf(stderr,"Read %d frames\n",nfr);
209 dt = (time[nfr-1] - time[0])/(nfr - 1);
210 /* Some ugly rounding to get nice nice times in the output */
211 dt = (int)(10000.0*dt + 0.5)/10000.0;
216 if (fmmax <= 0 || fmmax >= nfr)
219 nbin = (int)(rmax*invbin + 0.5);
224 mat_nx = sqrt(fmmax*dt)*invsbin + 1;
227 for(f=0; f<mat_nx; f++)
229 rmax2 = sqr(nbin*rbin);
230 /* Initialize time zero */
231 mat[0][0] = nfr*isize;
249 /* Initialize time zero */
256 msmul(avbox,1.0/nfr,avbox);
257 for(f=0; f<nfr; f++) {
259 fprintf(stderr,"\rProcessing frame %d",f);
260 /* Scale all the configuration to the average box */
261 m_inv_ur0(sbox[f],corr);
262 mmul_ur0(avbox,corr,corr);
263 for(i=0; i<isize; i++) {
264 mvmul_ur0(corr,sx[f][i],sx[f][i]);
266 /* Correct for periodic jumps */
267 for(m=DIM-1; m>=0; m--) {
268 while(sx[f][i][m] - sx[f-1][i][m] > 0.5*avbox[m][m])
269 rvec_dec(sx[f][i],avbox[m]);
270 while(sx[f][i][m] - sx[f-1][i][m] <= -0.5*avbox[m][m])
271 rvec_inc(sx[f][i],avbox[m]);
275 for(ff=0; ff<f; ff++) {
277 if (fbin <= fmmax || fbin <= ftmax) {
281 mbin = (int)(sqrt(fbin*dt)*invsbin + 0.5);
282 for(i=0; i<isize; i++) {
283 d2 = distance2(sx[f][i],sx[ff][i]);
284 if (mbin < mat_nx && d2 < rmax2) {
285 bin = (int)(sqrt(d2)*invbin + 0.5);
290 if (fbin <= ftmax && d2 <= rint2)
300 for(fbin=0; fbin<nr; fbin++) {
301 ff = f - (fbin + 1)*fshift;
303 for(i=0; i<isize; i++) {
304 d2 = distance2(sx[f][i],sx[ff][i]);
305 bin = (int)(sqrt(d2)*invbin);
307 nallocn = 10*(bin/10) + 11;
308 for(m=0; m<nr; m++) {
309 srenew(pr[m],nallocn);
310 for(i=nalloc; i<nallocn; i++)
322 fprintf(stderr,"\n");
326 for(f=0; f<mat_nx; f++) {
327 normfac = 1.0/(mcount[f]*isize*rbin);
328 for(i=0; i<nbin; i++) {
329 mat[f][i] *= normfac;
330 if (mat[f][i] > matmax && (f!=0 || i!=0))
334 fprintf(stdout,"Value at (0,0): %.3f, maximum of the rest %.3f\n",
339 for(f=0; f<mat_nx; f++) {
346 for(i=0; i<=nbin; i++)
348 fp = ffopen(matfile,"w");
349 write_xpm(fp,MAT_SPATIAL_Y,"Van Hove function","G (1/nm)",
350 sbin==0 ? "time (ps)" : "sqrt(time) (ps^1/2)","r (nm)",
351 mat_nx,nbin,tickx,ticky,mat,0,matmax,rlo,rhi,&nlev);
356 fp = xvgropen(orfile,"Van Hove function","r (nm)","G (nm\\S-1\\N)",oenv);
357 fprintf(fp,"@ subtitle \"for particles in group %s\"\n",grpname);
359 for(fbin=0; fbin<nr; fbin++) {
360 sprintf(buf,"%g ps",(fbin + 1)*fshift*dt);
361 legend[fbin] = strdup(buf);
363 xvgr_legend(fp,nr,(const char**)legend,oenv);
364 for(i=0; i<nalloc; i++) {
365 fprintf(fp,"%g",i*rbin);
366 for(fbin=0; fbin<nr; fbin++)
368 (real)pr[fbin][i]/(rcount[fbin]*isize*rbin*(i==0 ? 0.5 : 1)));
375 sprintf(buf,"Probability of moving less than %g nm",rint);
376 fp = xvgropen(otfile,buf,"t (ps)","",oenv);
377 fprintf(fp,"@ subtitle \"for particles in group %s\"\n",grpname);
378 for(f=0; f<=ftmax; f++)
379 fprintf(fp,"%g %g\n",f*dt,(real)pt[f]/(tcount[f]*isize));
383 do_view(oenv, matfile,NULL);
384 do_view(oenv, orfile,NULL);
385 do_view(oenv, otfile,NULL);