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49 #include "gromacs/fileio/tpxio.h"
50 #include "gromacs/fileio/trxio.h"
57 int gmx_filter(int argc, char *argv[])
59 const char *desc[] = {
60 "[TT]g_filter[tt] performs frequency filtering on a trajectory.",
61 "The filter shape is cos([GRK]pi[grk] t/A) + 1 from -A to +A, where A is given",
62 "by the option [TT]-nf[tt] times the time step in the input trajectory.",
63 "This filter reduces fluctuations with period A by 85%, with period",
64 "2*A by 50% and with period 3*A by 17% for low-pass filtering.",
65 "Both a low-pass and high-pass filtered trajectory can be written.[PAR]",
67 "Option [TT]-ol[tt] writes a low-pass filtered trajectory.",
68 "A frame is written every [TT]-nf[tt] input frames.",
69 "This ratio of filter length and output interval ensures a good",
70 "suppression of aliasing of high-frequency motion, which is useful for",
71 "making smooth movies. Also averages of properties which are linear",
72 "in the coordinates are preserved, since all input frames are weighted",
73 "equally in the output.",
74 "When all frames are needed, use the [TT]-all[tt] option.[PAR]",
76 "Option [TT]-oh[tt] writes a high-pass filtered trajectory.",
77 "The high-pass filtered coordinates are added to the coordinates",
78 "from the structure file. When using high-pass filtering use [TT]-fit[tt]",
79 "or make sure you use a trajectory that has been fitted on",
80 "the coordinates in the structure file."
84 static gmx_bool bNoJump = TRUE, bFit = FALSE, bLowAll = FALSE;
86 { "-nf", FALSE, etINT, {&nf},
87 "Sets the filter length as well as the output interval for low-pass filtering" },
88 { "-all", FALSE, etBOOL, {&bLowAll},
89 "Write all low-pass filtered frames" },
90 { "-nojump", FALSE, etBOOL, {&bNoJump},
91 "Remove jumps of atoms across the box" },
92 { "-fit", FALSE, etBOOL, {&bFit},
93 "Fit all frames to a reference structure" }
95 const char *topfile, *lowfile, *highfile;
96 gmx_bool bTop = FALSE;
100 matrix topbox, *box, boxf;
101 char title[256], *grpname;
106 t_trxstatus *outl, *outh;
107 int nffr, i, fr, nat, j, d, m;
109 real flen, *filt, sum, *t;
110 rvec xcmtop, xcm, **x, *ptr, *xf, *xn, *xp, hbox;
112 gmx_rmpbc_t gpbc = NULL;
114 #define NLEG asize(leg)
116 { efTRX, "-f", NULL, ffREAD },
117 { efTPS, NULL, NULL, ffOPTRD },
118 { efNDX, NULL, NULL, ffOPTRD },
119 { efTRO, "-ol", "lowpass", ffOPTWR },
120 { efTRO, "-oh", "highpass", ffOPTWR }
122 #define NFILE asize(fnm)
124 if (!parse_common_args(&argc, argv, PCA_CAN_TIME | PCA_CAN_VIEW | PCA_BE_NICE,
125 NFILE, fnm, asize(pa), pa, asize(desc), desc, 0, NULL, &oenv))
130 highfile = opt2fn_null("-oh", NFILE, fnm);
133 topfile = ftp2fn(efTPS, NFILE, fnm);
134 lowfile = opt2fn_null("-ol", NFILE, fnm);
138 topfile = ftp2fn_null(efTPS, NFILE, fnm);
139 lowfile = opt2fn("-ol", NFILE, fnm);
143 bTop = read_tps_conf(ftp2fn(efTPS, NFILE, fnm), title, &top, &ePBC,
144 &xtop, NULL, topbox, TRUE);
147 gpbc = gmx_rmpbc_init(&top.idef, ePBC, top.atoms.nr);
148 gmx_rmpbc(gpbc, top.atoms.nr, topbox, xtop);
155 fprintf(stderr, "Select group for least squares fit\n");
156 get_index(&top.atoms, ftp2fn_null(efNDX, NFILE, fnm), 1, &isize, &index, &grpname);
158 snew(w_rls, top.atoms.nr);
159 for (i = 0; i < isize; i++)
161 w_rls[index[i]] = top.atoms.atom[index[i]].m;
163 calc_xcm(xtop, isize, index, top.atoms.atom, xcmtop, FALSE);
164 for (j = 0; j < top.atoms.nr; j++)
166 rvec_dec(xtop[j], xcmtop);
170 /* The actual filter length flen can actually be any real number */
172 /* nffr is the number of frames that we filter over */
176 for (i = 0; i < nffr; i++)
178 filt[i] = cos(2*M_PI*(i - nf + 1)/(real)flen) + 1;
181 fprintf(stdout, "filter weights:");
182 for (i = 0; i < nffr; i++)
185 fprintf(stdout, " %5.3f", filt[i]);
187 fprintf(stdout, "\n");
193 nat = read_first_x(oenv, &in, opt2fn("-f", NFILE, fnm),
194 &(t[nffr - 1]), &(x[nffr - 1]), box[nffr - 1]);
196 for (i = 0; i < nat; i++)
200 /* x[nffr - 1] was already allocated by read_first_x */
201 for (i = 0; i < nffr-1; i++)
208 outl = open_trx(lowfile, "w");
216 outh = open_trx(highfile, "w");
227 if (bNoJump && fr > 0)
230 for (j = 0; j < nat; j++)
232 for (d = 0; d < DIM; d++)
234 hbox[d] = 0.5*box[nffr - 1][d][d];
237 for (i = 0; i < nat; i++)
239 for (m = DIM-1; m >= 0; m--)
243 while (xn[i][m] - xp[i][m] <= -hbox[m])
245 for (d = 0; d <= m; d++)
247 xn[i][d] += box[nffr - 1][m][d];
250 while (xn[i][m] - xp[i][m] > hbox[m])
252 for (d = 0; d <= m; d++)
254 xn[i][d] -= box[nffr - 1][m][d];
263 gmx_rmpbc(gpbc, nat, box[nffr - 1], xn);
267 calc_xcm(xn, isize, index, top.atoms.atom, xcm, FALSE);
268 for (j = 0; j < nat; j++)
270 rvec_dec(xn[j], xcm);
272 do_fit(nat, w_rls, xtop, xn);
273 for (j = 0; j < nat; j++)
275 rvec_inc(xn[j], xcmtop);
278 if (fr >= nffr && (outh || bLowAll || fr % nf == nf - 1))
280 /* Lowpass filtering */
281 for (j = 0; j < nat; j++)
286 for (i = 0; i < nffr; i++)
288 for (j = 0; j < nat; j++)
290 for (d = 0; d < DIM; d++)
292 xf[j][d] += filt[i]*x[i][j][d];
295 for (j = 0; j < DIM; j++)
297 for (d = 0; d < DIM; d++)
299 boxf[j][d] += filt[i]*box[i][j][d];
303 if (outl && (bLowAll || fr % nf == nf - 1))
305 write_trx(outl, nat, ind, topfile ? &(top.atoms) : NULL,
306 0, t[nf - 1], bFit ? topbox : boxf, xf, NULL, NULL);
310 /* Highpass filtering */
311 for (j = 0; j < nat; j++)
313 for (d = 0; d < DIM; d++)
315 xf[j][d] = xtop[j][d] + x[nf - 1][j][d] - xf[j][d];
320 for (j = 0; j < nat; j++)
322 rvec_inc(xf[j], xcmtop);
325 for (j = 0; j < DIM; j++)
327 for (d = 0; d < DIM; d++)
329 boxf[j][d] = topbox[j][d] + box[nf - 1][j][d] - boxf[j][d];
332 write_trx(outh, nat, ind, topfile ? &(top.atoms) : NULL,
333 0, t[nf - 1], bFit ? topbox : boxf, xf, NULL, NULL);
336 /* Cycle all the pointer and the box by one */
338 for (i = 0; i < nffr-1; i++)
342 copy_mat(box[i+1], box[i]);
347 while (read_next_x(oenv, in, &(t[nffr - 1]), x[nffr - 1], box[nffr - 1]));
351 gmx_rmpbc_done(gpbc);