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33 * GROningen Mixture of Alchemy and Childrens' Stories
45 #include "gmx_fatal.h"
63 typedef struct gmx_structurefactors {
65 int *p; /* proton number */
66 int *n; /* neutron number */
67 /* Parameters for the Cromer Mann fit */
68 real **a; /* parameter a */
69 real **b; /* parameter b */
70 real *c; /* parameter c */
71 char **atomnm; /* atomname */
73 } gmx_structurefactors;
75 typedef struct reduced_atom{
81 typedef struct structure_factor
95 extern int * create_indexed_atom_type (reduced_atom_t * atm, int size)
98 * create an index of the atom types found in a group
99 * i.e.: for water index_atp[0]=type_number_of_O and
100 * index_atp[1]=type_number_of_H
102 * the last element is set to 0
104 int *index_atp, i, i_tmp, j;
106 reduced_atom *att=(reduced_atom *)atm;
110 index_atp[0] = att[0].t;
111 for (i = 1; i < size; i++) {
112 for (j = 0; j < i_tmp; j++)
113 if (att[i].t == index_atp[j])
115 if (j == i_tmp) { /* i.e. no indexed atom type is == to atm[i].t */
117 srenew (index_atp, i_tmp * sizeof (int));
118 index_atp[i_tmp - 1] = att[i].t;
122 srenew (index_atp, i_tmp * sizeof (int));
123 index_atp[i_tmp - 1] = 0;
129 extern t_complex *** rc_tensor_allocation(int x, int y, int z)
134 t = (t_complex ***)calloc(x,sizeof(t_complex**));
135 if(!t) exit(fprintf(stderr,"\nallocation error"));
136 t[0] = (t_complex **)calloc(x*y,sizeof(t_complex*));
137 if(!t[0]) exit(fprintf(stderr,"\nallocation error"));
138 t[0][0] = (t_complex *)calloc(x*y*z,sizeof(t_complex));
139 if(!t[0][0]) exit(fprintf(stderr,"\nallocation error"));
141 for( j = 1 ; j < y ; j++)
142 t[0][j] = t[0][j-1] + z;
143 for( i = 1 ; i < x ; i++) {
145 t[i][0] = t[i-1][0] + y*z;
146 for( j = 1 ; j < y ; j++)
147 t[i][j] = t[i][j-1] + z;
153 extern void compute_structure_factor (structure_factor_t * sft, matrix box,
154 reduced_atom_t * red, int isize, real start_q,
155 real end_q, int group,real **sf_table)
157 structure_factor *sf=(structure_factor *)sft;
158 reduced_atom *redt=(reduced_atom *)red;
162 real kdotx, asf, kx, ky, kz, krr;
163 int kr, maxkx, maxky, maxkz, i, j, k, p, *counter;
166 k_factor[XX] = 2 * M_PI / box[XX][XX];
167 k_factor[YY] = 2 * M_PI / box[YY][YY];
168 k_factor[ZZ] = 2 * M_PI / box[ZZ][ZZ];
170 maxkx = (int) (end_q / k_factor[XX] + 0.5);
171 maxky = (int) (end_q / k_factor[YY] + 0.5);
172 maxkz = (int) (end_q / k_factor[ZZ] + 0.5);
174 snew (counter, sf->n_angles);
176 tmpSF = rc_tensor_allocation(maxkx,maxky,maxkz);
179 * compute real and imaginary part of the structure factor for every
182 fprintf(stderr,"\n");
183 for (i = 0; i < maxkx; i++) {
184 fprintf (stderr,"\rdone %3.1f%% ", (double)(100.0*(i+1))/maxkx);
185 kx = i * k_factor[XX];
186 for (j = 0; j < maxky; j++) {
187 ky = j * k_factor[YY];
188 for (k = 0; k < maxkz; k++)
189 if (i != 0 || j != 0 || k != 0) {
190 kz = k * k_factor[ZZ];
191 krr = sqrt (sqr (kx) + sqr (ky) + sqr (kz));
192 if (krr >= start_q && krr <= end_q) {
193 kr = (int) (krr/sf->ref_k + 0.5);
194 if (kr < sf->n_angles) {
195 counter[kr]++; /* will be used for the copmutation
197 for (p = 0; p < isize; p++) {
198 asf = sf_table[redt[p].t][kr];
200 kdotx = kx * redt[p].x[XX] +
201 ky * redt[p].x[YY] + kz * redt[p].x[ZZ];
203 tmpSF[i][j][k].re += cos (kdotx) * asf;
204 tmpSF[i][j][k].im += sin (kdotx) * asf;
210 } /* end loop on i */
212 * compute the square modulus of the structure factor, averaging on the surface
213 * kx*kx + ky*ky + kz*kz = krr*krr
214 * note that this is correct only for a (on the macroscopic scale)
217 for (i = 0; i < maxkx; i++) {
218 kx = i * k_factor[XX]; for (j = 0; j < maxky; j++) {
219 ky = j * k_factor[YY]; for (k = 0; k < maxkz; k++) {
220 kz = k * k_factor[ZZ]; krr = sqrt (sqr (kx) + sqr (ky)
221 + sqr (kz)); if (krr >= start_q && krr <= end_q) {
222 kr = (int) (krr / sf->ref_k + 0.5);
223 if (kr < sf->n_angles && counter[kr] != 0)
225 (sqr (tmpSF[i][j][k].re) +
226 sqr (tmpSF[i][j][k].im))/ counter[kr];
230 } sfree (counter); free(tmpSF[0][0]); free(tmpSF[0]); free(tmpSF);
234 extern gmx_structurefactors_t *gmx_structurefactors_init(const char *datfn) {
236 /* Read the database for the structure factor of the different atoms */
240 gmx_structurefactors *gsf;
241 double a1,a2,a3,a4,b1,b2,b3,b4,c;
251 snew(gsf->atomnm,nralloc);
252 snew(gsf->a,nralloc);
253 snew(gsf->b,nralloc);
254 snew(gsf->c,nralloc);
255 snew(gsf->p,nralloc);
257 gsf->nratoms=line_no;
258 while(get_a_line(fp,line,STRLEN)) {
260 if (sscanf(line,"%s %d %lf %lf %lf %lf %lf %lf %lf %lf %lf",
261 atomn,&p,&a1,&a2,&a3,&a4,&b1,&b2,&b3,&b4,&c) == 11) {
262 gsf->atomnm[i]=strdup(atomn);
276 gsf->nratoms=line_no;
277 if (line_no==nralloc){
279 srenew(gsf->atomnm,nralloc);
280 srenew(gsf->a,nralloc);
281 srenew(gsf->b,nralloc);
282 srenew(gsf->c,nralloc);
283 srenew(gsf->p,nralloc);
287 fprintf(stderr,"WARNING: Error in file %s at line %d ignored\n",
291 srenew(gsf->atomnm,gsf->nratoms);
292 srenew(gsf->a,gsf->nratoms);
293 srenew(gsf->b,gsf->nratoms);
294 srenew(gsf->c,gsf->nratoms);
295 srenew(gsf->p,gsf->nratoms);
299 return (gmx_structurefactors_t *) gsf;
304 extern void rearrange_atoms (reduced_atom_t * positions, t_trxframe *fr, atom_id * index,
305 int isize, t_topology * top, gmx_bool flag,gmx_structurefactors_t *gsf)
306 /* given the group's index, return the (continuous) array of atoms */
310 reduced_atom *pos=(reduced_atom *)positions;
313 for (i = 0; i < isize; i++)
315 return_atom_type (*(top->atoms.atomname[index[i]]),gsf);
316 for (i = 0; i < isize; i++)
317 copy_rvec (fr->x[index[i]], pos[i].x);
319 positions=(reduced_atom_t *)pos;
323 extern int return_atom_type (const char *name,gmx_structurefactors_t *gsf)
330 { "CH1", 1 }, { "CH2", 2 }, { "CH3", 3 },
331 { "CS1", 1 }, { "CS2", 2 }, { "CS3", 3 },
332 { "CP1", 1 }, { "CP2", 2 }, { "CP3", 3 }
340 gmx_structurefactors *gsft=(gmx_structurefactors *)gsf;
346 for(i=0; (i<asize(uh)); i++)
347 if (strcmp(name,uh[i].name) == 0)
348 return NCMT-1+uh[i].nh;
350 for(i=0; (i<NCMT); i++){
351 if (strncmp (name, gsft->atomnm[i],strlen(gsft->atomnm[i])) == 0){
358 gmx_fatal(FARGS,"\nError: atom (%s) not in list (%d types checked)!\n",
363 if(strlen(gsft->atomnm[tndx[i]])>(size_t)nrc){
364 nrc=strlen(gsft->atomnm[tndx[i]]);
375 extern int gmx_structurefactors_get_sf(gmx_structurefactors_t *gsf, int elem, real a[4], real b[4], real *c){
379 gmx_structurefactors *gsft=(gmx_structurefactors *)gsf;
383 a[i]=gsft->a[elem][i];
384 b[i]=gsft->b[elem][i];
392 extern int do_scattering_intensity (const char* fnTPS, const char* fnNDX,
393 const char* fnXVG, const char *fnTRX,
395 real start_q,real end_q,
396 real energy,int ng,const output_env_t oenv)
398 int i,*isize,flags = TRX_READ_X,**index_atp;
400 char **grpname,title[STRLEN];
405 reduced_atom_t **red;
406 structure_factor *sf;
413 gmx_structurefactors_t *gmx_sf;
421 gmx_sf=gmx_structurefactors_init(fnDAT);
423 success=gmx_structurefactors_get_sf(gmx_sf,0, a, b, &c);
428 /* Read the topology informations */
429 read_tps_conf (fnTPS, title, &top, &ePBC, &xtop, NULL, box, TRUE);
432 /* groups stuff... */
437 fprintf (stderr, "\nSelect %d group%s\n", ng,
440 get_index (&top.atoms, fnNDX, ng, isize, index, grpname);
442 rd_index (fnNDX, ng, isize, index, grpname);
444 /* The first time we read data is a little special */
445 read_first_frame (oenv,&status, fnTRX, &fr, flags);
447 sf->total_n_atoms = fr.natoms;
450 snew (index_atp, ng);
452 r_tmp = max (box[XX][XX], box[YY][YY]);
453 r_tmp = (double) max (box[ZZ][ZZ], r_tmp);
455 sf->ref_k = (2.0 * M_PI) / (r_tmp);
456 /* ref_k will be the reference momentum unit */
457 sf->n_angles = (int) (end_q / sf->ref_k + 0.5);
460 for (i = 0; i < ng; i++)
461 snew (sf->F[i], sf->n_angles);
462 for (i = 0; i < ng; i++) {
463 snew (red[i], isize[i]);
464 rearrange_atoms (red[i], &fr, index[i], isize[i], &top, TRUE,gmx_sf);
465 index_atp[i] = create_indexed_atom_type (red[i], isize[i]);
468 sf_table = compute_scattering_factor_table (gmx_sf,(structure_factor_t *)sf,&nsftable);
471 /* This is the main loop over frames */
475 for (i = 0; i < ng; i++) {
476 rearrange_atoms (red[i], &fr, index[i], isize[i], &top,FALSE,gmx_sf);
478 compute_structure_factor ((structure_factor_t *)sf, box, red[i], isize[i],
479 start_q, end_q, i, sf_table);
483 while (read_next_frame (oenv,status, &fr));
485 save_data ((structure_factor_t *)sf, fnXVG, ng, start_q, end_q,oenv);
491 gmx_structurefactors_done(gmx_sf);
497 extern void save_data (structure_factor_t *sft, const char *file, int ngrps,
498 real start_q, real end_q, const output_env_t oenv)
503 double *tmp, polarization_factor, A;
505 structure_factor *sf=(structure_factor *)sft;
507 fp = xvgropen (file, "Scattering Intensity", "q (1/nm)",
508 "Intensity (a.u.)",oenv);
512 for (g = 0; g < ngrps; g++)
513 for (i = 0; i < sf->n_angles; i++) {
516 * theta is half the angle between incoming and scattered vectors.
518 * polar. fact. = 0.5*(1+cos^2(2*theta)) = 1 - 0.5 * sin^2(2*theta)
520 * sin(theta) = q/(2k) := A -> sin^2(theta) = 4*A^2 (1-A^2) ->
521 * -> 0.5*(1+cos^2(2*theta)) = 1 - 2 A^2 (1-A^2)
523 A = (double) (i * sf->ref_k) / (2.0 * sf->momentum);
524 polarization_factor = 1 - 2.0 * sqr (A) * (1 - sqr (A));
525 sf->F[g][i] *= polarization_factor;
527 for (i = 0; i < sf->n_angles; i++) {
528 if (i * sf->ref_k >= start_q && i * sf->ref_k <= end_q) {
529 fprintf (fp, "%10.5f ", i * sf->ref_k);
530 for (g = 0; g < ngrps; g++)
531 fprintf (fp, " %10.5f ", (sf->F[g][i]) /( sf->total_n_atoms*
541 extern double CMSF (gmx_structurefactors_t *gsf,int type,int nh,double lambda, double sin_theta)
543 * return Cromer-Mann fit for the atomic scattering factor:
544 * sin_theta is the sine of half the angle between incoming and scattered
545 * vectors. See g_sq.h for a short description of CM fit.
549 double tmp = 0.0, k2;
558 * f0[k] = c + [SUM a_i*EXP(-b_i*(k^2)) ]
567 tmp = (CMSF (gsf,return_atom_type ("C",gsf),0,lambda, sin_theta) +
568 nh*CMSF (gsf,return_atom_type ("H",gsf),0,lambda, sin_theta));
572 k2 = (sqr (sin_theta) / sqr (10.0 * lambda));
573 success=gmx_structurefactors_get_sf(gsf,type,a,b,&c);
575 for (i = 0; (i < 4); i++)
576 tmp += a[i] * exp (-b[i] * k2);
583 extern real **gmx_structurefactors_table(gmx_structurefactors_t *gsf,real momentum, real ref_k, real lambda, int n_angles){
590 gmx_structurefactors *gsft=(gmx_structurefactors *)gsf;
595 snew (sf_table,nsftable);
596 for (i = 0; (i < nsftable); i++) {
597 snew (sf_table[i], n_angles);
598 for (j = 0; j < n_angles; j++) {
599 q = ((double) j * ref_k);
600 /* theta is half the angle between incoming
601 and scattered wavevectors. */
602 sin_theta = q / (2.0 * momentum);
604 sf_table[i][j] = CMSF (gsf,i,0,lambda, sin_theta);
607 sf_table[i][j] = CMSF (gsf,i,i-NCMT+1,lambda, sin_theta);
613 extern void gmx_structurefactors_done(gmx_structurefactors_t *gsf){
616 gmx_structurefactors *sf;
617 sf=(gmx_structurefactors *) gsf;
619 for(i=0;i<sf->nratoms;i++){
622 sfree(sf->atomnm[i]);
635 extern real **compute_scattering_factor_table (gmx_structurefactors_t *gsf,structure_factor_t *sft,int *nsftable)
638 * this function build up a table of scattering factors for every atom
639 * type and for every scattering angle.
645 structure_factor *sf=(structure_factor *)sft;
648 /* \hbar \omega \lambda = hc = 1239.842 eV * nm */
649 sf->momentum = ((double) (2. * 1000.0 * M_PI * sf->energy) / hc);
650 sf->lambda = hc / (1000.0 * sf->energy);
651 fprintf (stderr, "\nwavelenght = %f nm\n", sf->lambda);
653 sf_table=gmx_structurefactors_table(gsf,sf->momentum,sf->ref_k,sf->lambda,sf->n_angles);