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41 #include "gromacs/commandline/pargs.h"
42 #include "gromacs/fileio/trxio.h"
43 #include "gromacs/fileio/xvgr.h"
44 #include "gromacs/gmxana/gmx_ana.h"
45 #include "gromacs/gmxana/gstat.h"
46 #include "gromacs/math/do_fit.h"
47 #include "gromacs/math/utilities.h"
48 #include "gromacs/math/vec.h"
49 #include "gromacs/pbcutil/pbc.h"
50 #include "gromacs/pbcutil/rmpbc.h"
51 #include "gromacs/topology/index.h"
52 #include "gromacs/topology/topology.h"
53 #include "gromacs/utility/arraysize.h"
54 #include "gromacs/utility/fatalerror.h"
55 #include "gromacs/utility/futil.h"
56 #include "gromacs/utility/smalloc.h"
58 int gmx_helixorient(int argc
, char* argv
[])
60 const char* desc
[] = {
61 "[THISMODULE] calculates the coordinates and direction of the average",
62 "axis inside an alpha helix, and the direction/vectors of both the",
63 "C[GRK]alpha[grk] and (optionally) a sidechain atom relative to the axis.[PAR]",
64 "As input, you need to specify an index group with C[GRK]alpha[grk] atoms",
65 "corresponding to an [GRK]alpha[grk]-helix of continuous residues. Sidechain",
66 "directions require a second index group of the same size, containing",
67 "the heavy atom in each residue that should represent the sidechain.[PAR]",
68 "[BB]Note[bb] that this program does not do any fitting of structures.[PAR]",
69 "We need four C[GRK]alpha[grk] coordinates to define the local direction of the helix",
71 "The tilt/rotation is calculated from Euler rotations, where we define",
72 "the helix axis as the local [IT]x[it]-axis, the residues/C[GRK]alpha[grk] vector as ",
74 "[IT]z[it]-axis from their cross product. We use the Euler Y-Z-X rotation, meaning",
75 "we first tilt the helix axis (1) around and (2) orthogonal to the residues",
76 "vector, and finally apply the (3) rotation around it. For debugging or other",
77 "purposes, we also write out the actual Euler rotation angles as [TT]theta[1-3].xvg[tt]"
80 t_topology
* top
= nullptr;
86 real theta1
, theta2
, theta3
;
102 rvec
* residuehelixaxis
;
105 rvec
* sidechainvector
;
107 rvec
* residuehelixaxis_t0
;
108 rvec
* residuevector_t0
;
110 rvec
* residuehelixaxis_tlast
;
111 rvec
* residuevector_tlast
;
113 rvec refaxes
[3], newaxes
[3];
115 rvec rot_refaxes
[3], rot_newaxes
[3];
119 real
*twist
, *residuetwist
;
120 real
*radius
, *residueradius
;
121 real
*rise
, *residuerise
;
122 real
* residuebending
;
129 FILE * fpaxis
, *fpcenter
, *fptilt
, *fprotation
;
130 FILE * fpradius
, *fprise
, *fptwist
;
131 FILE * fptheta1
, *fptheta2
, *fptheta3
;
135 gmx_output_env_t
* oenv
;
136 gmx_rmpbc_t gpbc
= nullptr;
138 static gmx_bool bSC
= FALSE
;
139 static gmx_bool bIncremental
= FALSE
;
141 static t_pargs pa
[] = {
146 "Calculate sidechain directions relative to helix axis too." },
151 "Calculate incremental rather than total rotation/tilt." },
153 #define NPA asize(pa)
156 { efTPR
, nullptr, nullptr, ffREAD
}, { efTRX
, "-f", nullptr, ffREAD
},
157 { efNDX
, nullptr, nullptr, ffOPTRD
}, { efDAT
, "-oaxis", "helixaxis", ffWRITE
},
158 { efDAT
, "-ocenter", "center", ffWRITE
}, { efXVG
, "-orise", "rise", ffWRITE
},
159 { efXVG
, "-oradius", "radius", ffWRITE
}, { efXVG
, "-otwist", "twist", ffWRITE
},
160 { efXVG
, "-obending", "bending", ffWRITE
}, { efXVG
, "-otilt", "tilt", ffWRITE
},
161 { efXVG
, "-orot", "rotation", ffWRITE
}
163 #define NFILE asize(fnm)
165 if (!parse_common_args(&argc
, argv
, PCA_CAN_TIME
, NFILE
, fnm
, NPA
, pa
, asize(desc
), desc
, 0,
171 top
= read_top(ftp2fn(efTPR
, NFILE
, fnm
), &pbcType
);
173 for (i
= 0; i
< 3; i
++)
178 /* read index files */
179 printf("Select a group of Calpha atoms corresponding to a single continuous helix:\n");
180 get_index(&(top
->atoms
), ftp2fn_null(efNDX
, NFILE
, fnm
), 1, &iCA
, &ind_CA
, &gn_CA
);
182 snew(x_SC
, iCA
); /* sic! */
187 snew(diff13
, iCA
- 3);
188 snew(diff24
, iCA
- 3);
189 snew(helixaxis
, iCA
- 3);
191 snew(residuetwist
, iCA
);
193 snew(residueradius
, iCA
);
195 snew(residuerise
, iCA
);
196 snew(residueorigin
, iCA
);
197 snew(residuehelixaxis
, iCA
);
198 snew(residuevector
, iCA
);
199 snew(sidechainvector
, iCA
);
200 snew(residuebending
, iCA
);
201 snew(residuehelixaxis_t0
, iCA
);
202 snew(residuevector_t0
, iCA
);
204 snew(residuehelixaxis_tlast
, iCA
);
205 snew(residuevector_tlast
, iCA
);
206 snew(axis3_tlast
, iCA
);
211 printf("Select a group of atoms defining the sidechain direction (1/residue):\n");
212 get_index(&(top
->atoms
), ftp2fn_null(efNDX
, NFILE
, fnm
), 1, &iSC
, &ind_SC
, &gn_SC
);
215 gmx_fatal(FARGS
, "Number of sidechain atoms (%d) != number of CA atoms (%d)", iSC
, iCA
);
219 natoms
= read_first_x(oenv
, &status
, ftp2fn(efTRX
, NFILE
, fnm
), &t
, &x
, box
);
221 fpaxis
= gmx_ffopen(opt2fn("-oaxis", NFILE
, fnm
), "w");
222 fpcenter
= gmx_ffopen(opt2fn("-ocenter", NFILE
, fnm
), "w");
223 fprise
= gmx_ffopen(opt2fn("-orise", NFILE
, fnm
), "w");
224 fpradius
= gmx_ffopen(opt2fn("-oradius", NFILE
, fnm
), "w");
225 fptwist
= gmx_ffopen(opt2fn("-otwist", NFILE
, fnm
), "w");
226 fpbending
= gmx_ffopen(opt2fn("-obending", NFILE
, fnm
), "w");
228 fptheta1
= gmx_ffopen("theta1.xvg", "w");
229 fptheta2
= gmx_ffopen("theta2.xvg", "w");
230 fptheta3
= gmx_ffopen("theta3.xvg", "w");
234 fptilt
= xvgropen(opt2fn("-otilt", NFILE
, fnm
), "Incremental local helix tilt", "Time(ps)",
235 "Tilt (degrees)", oenv
);
236 fprotation
= xvgropen(opt2fn("-orot", NFILE
, fnm
), "Incremental local helix rotation",
237 "Time(ps)", "Rotation (degrees)", oenv
);
241 fptilt
= xvgropen(opt2fn("-otilt", NFILE
, fnm
), "Cumulative local helix tilt", "Time(ps)",
242 "Tilt (degrees)", oenv
);
243 fprotation
= xvgropen(opt2fn("-orot", NFILE
, fnm
), "Cumulative local helix rotation",
244 "Time(ps)", "Rotation (degrees)", oenv
);
247 clear_rvecs(3, unitaxes
);
252 gpbc
= gmx_rmpbc_init(&top
->idef
, pbcType
, natoms
);
256 /* initialisation for correct distance calculations */
257 set_pbc(&pbc
, pbcType
, box
);
258 /* make molecules whole again */
259 gmx_rmpbc(gpbc
, natoms
, box
, x
);
261 /* copy coords to our smaller arrays */
262 for (i
= 0; i
< iCA
; i
++)
264 copy_rvec(x
[ind_CA
[i
]], x_CA
[i
]);
267 copy_rvec(x
[ind_SC
[i
]], x_SC
[i
]);
271 for (i
= 0; i
< iCA
- 3; i
++)
273 rvec_sub(x_CA
[i
+ 1], x_CA
[i
], r12
[i
]);
274 rvec_sub(x_CA
[i
+ 2], x_CA
[i
+ 1], r23
[i
]);
275 rvec_sub(x_CA
[i
+ 3], x_CA
[i
+ 2], r34
[i
]);
276 rvec_sub(r12
[i
], r23
[i
], diff13
[i
]);
277 rvec_sub(r23
[i
], r34
[i
], diff24
[i
]);
278 /* calculate helix axis */
279 cprod(diff13
[i
], diff24
[i
], helixaxis
[i
]);
280 svmul(1.0 / norm(helixaxis
[i
]), helixaxis
[i
], helixaxis
[i
]);
282 tmp
= cos_angle(diff13
[i
], diff24
[i
]);
283 twist
[i
] = 180.0 / M_PI
* std::acos(tmp
);
284 radius
[i
] = std::sqrt(norm(diff13
[i
]) * norm(diff24
[i
])) / (2.0 * (1.0 - tmp
));
285 rise
[i
] = std::abs(iprod(r23
[i
], helixaxis
[i
]));
287 svmul(radius
[i
] / norm(diff13
[i
]), diff13
[i
], v1
);
288 svmul(radius
[i
] / norm(diff24
[i
]), diff24
[i
], v2
);
290 rvec_sub(x_CA
[i
+ 1], v1
, residueorigin
[i
+ 1]);
291 rvec_sub(x_CA
[i
+ 2], v2
, residueorigin
[i
+ 2]);
293 residueradius
[0] = residuetwist
[0] = residuerise
[0] = 0;
295 residueradius
[1] = radius
[0];
296 residuetwist
[1] = twist
[0];
297 residuerise
[1] = rise
[0];
299 residuebending
[0] = residuebending
[1] = 0;
300 for (i
= 2; i
< iCA
- 2; i
++)
302 residueradius
[i
] = 0.5 * (radius
[i
- 2] + radius
[i
- 1]);
303 residuetwist
[i
] = 0.5 * (twist
[i
- 2] + twist
[i
- 1]);
304 residuerise
[i
] = 0.5 * (rise
[i
- 2] + rise
[i
- 1]);
305 residuebending
[i
] = 180.0 / M_PI
* std::acos(cos_angle(helixaxis
[i
- 2], helixaxis
[i
- 1]));
307 residueradius
[iCA
- 2] = radius
[iCA
- 4];
308 residuetwist
[iCA
- 2] = twist
[iCA
- 4];
309 residuerise
[iCA
- 2] = rise
[iCA
- 4];
310 residueradius
[iCA
- 1] = residuetwist
[iCA
- 1] = residuerise
[iCA
- 1] = 0;
311 residuebending
[iCA
- 2] = residuebending
[iCA
- 1] = 0;
313 clear_rvec(residueorigin
[0]);
314 clear_rvec(residueorigin
[iCA
- 1]);
316 /* average helix axes to define them on the residues.
317 * Just extrapolate second first/list atom.
319 copy_rvec(helixaxis
[0], residuehelixaxis
[0]);
320 copy_rvec(helixaxis
[0], residuehelixaxis
[1]);
322 for (i
= 2; i
< iCA
- 2; i
++)
324 rvec_add(helixaxis
[i
- 2], helixaxis
[i
- 1], residuehelixaxis
[i
]);
325 svmul(0.5, residuehelixaxis
[i
], residuehelixaxis
[i
]);
327 copy_rvec(helixaxis
[iCA
- 4], residuehelixaxis
[iCA
- 2]);
328 copy_rvec(helixaxis
[iCA
- 4], residuehelixaxis
[iCA
- 1]);
330 /* Normalize the axis */
331 for (i
= 0; i
< iCA
; i
++)
333 svmul(1.0 / norm(residuehelixaxis
[i
]), residuehelixaxis
[i
], residuehelixaxis
[i
]);
336 /* calculate vector from origin to residue CA */
337 fprintf(fpaxis
, "%15.12g ", t
);
338 fprintf(fpcenter
, "%15.12g ", t
);
339 fprintf(fprise
, "%15.12g ", t
);
340 fprintf(fpradius
, "%15.12g ", t
);
341 fprintf(fptwist
, "%15.12g ", t
);
342 fprintf(fpbending
, "%15.12g ", t
);
344 for (i
= 0; i
< iCA
; i
++)
346 if (i
== 0 || i
== iCA
- 1)
348 fprintf(fpaxis
, "%15.12g %15.12g %15.12g ", 0.0, 0.0, 0.0);
349 fprintf(fpcenter
, "%15.12g %15.12g %15.12g ", 0.0, 0.0, 0.0);
350 fprintf(fprise
, "%15.12g ", 0.0);
351 fprintf(fpradius
, "%15.12g ", 0.0);
352 fprintf(fptwist
, "%15.12g ", 0.0);
353 fprintf(fpbending
, "%15.12g ", 0.0);
357 rvec_sub(bSC
? x_SC
[i
] : x_CA
[i
], residueorigin
[i
], residuevector
[i
]);
358 svmul(1.0 / norm(residuevector
[i
]), residuevector
[i
], residuevector
[i
]);
359 cprod(residuehelixaxis
[i
], residuevector
[i
], axis3
[i
]);
360 fprintf(fpaxis
, "%15.12g %15.12g %15.12g ", residuehelixaxis
[i
][0],
361 residuehelixaxis
[i
][1], residuehelixaxis
[i
][2]);
362 fprintf(fpcenter
, "%15.12g %15.12g %15.12g ", residueorigin
[i
][0],
363 residueorigin
[i
][1], residueorigin
[i
][2]);
365 fprintf(fprise
, "%15.12g ", residuerise
[i
]);
366 fprintf(fpradius
, "%15.12g ", residueradius
[i
]);
367 fprintf(fptwist
, "%15.12g ", residuetwist
[i
]);
368 fprintf(fpbending
, "%15.12g ", residuebending
[i
]);
371 fprintf(fprise
, "\n");
372 fprintf(fpradius
, "\n");
373 fprintf(fpaxis
, "\n");
374 fprintf(fpcenter
, "\n");
375 fprintf(fptwist
, "\n");
376 fprintf(fpbending
, "\n");
380 for (i
= 0; i
< iCA
; i
++)
382 copy_rvec(residuehelixaxis
[i
], residuehelixaxis_t0
[i
]);
383 copy_rvec(residuevector
[i
], residuevector_t0
[i
]);
384 copy_rvec(axis3
[i
], axis3_t0
[i
]);
389 fprintf(fptilt
, "%15.12g ", t
);
390 fprintf(fprotation
, "%15.12g ", t
);
391 fprintf(fptheta1
, "%15.12g ", t
);
392 fprintf(fptheta2
, "%15.12g ", t
);
393 fprintf(fptheta3
, "%15.12g ", t
);
395 for (i
= 0; i
< iCA
; i
++)
397 if (i
== 0 || i
== iCA
- 1)
405 /* Total rotation & tilt */
406 copy_rvec(residuehelixaxis_t0
[i
], refaxes
[0]);
407 copy_rvec(residuevector_t0
[i
], refaxes
[1]);
408 copy_rvec(axis3_t0
[i
], refaxes
[2]);
412 /* Rotation/tilt since last step */
413 copy_rvec(residuehelixaxis_tlast
[i
], refaxes
[0]);
414 copy_rvec(residuevector_tlast
[i
], refaxes
[1]);
415 copy_rvec(axis3_tlast
[i
], refaxes
[2]);
417 copy_rvec(residuehelixaxis
[i
], newaxes
[0]);
418 copy_rvec(residuevector
[i
], newaxes
[1]);
419 copy_rvec(axis3
[i
], newaxes
[2]);
421 /* rotate reference frame onto unit axes */
422 calc_fit_R(3, 3, weight
, unitaxes
, refaxes
, A
);
423 for (j
= 0; j
< 3; j
++)
425 mvmul(A
, refaxes
[j
], rot_refaxes
[j
]);
426 mvmul(A
, newaxes
[j
], rot_newaxes
[j
]);
429 /* Determine local rotation matrix A */
430 calc_fit_R(3, 3, weight
, rot_newaxes
, rot_refaxes
, A
);
431 /* Calculate euler angles, from rotation order y-z-x, where
432 * x is helixaxis, y residuevector, and z axis3.
434 * A contains rotation column vectors.
437 theta1
= 180.0 / M_PI
* std::atan2(A
[0][2], A
[0][0]);
438 theta2
= 180.0 / M_PI
* std::asin(-A
[0][1]);
439 theta3
= 180.0 / M_PI
* std::atan2(A
[2][1], A
[1][1]);
441 tilt
= std::sqrt(theta1
* theta1
+ theta2
* theta2
);
443 fprintf(fptheta1
, "%15.12g ", theta1
);
444 fprintf(fptheta2
, "%15.12g ", theta2
);
445 fprintf(fptheta3
, "%15.12g ", theta3
);
447 fprintf(fptilt
, "%15.12g ", tilt
);
448 fprintf(fprotation
, "%15.12g ", rotation
);
450 fprintf(fptilt
, "\n");
451 fprintf(fprotation
, "\n");
452 fprintf(fptheta1
, "\n");
453 fprintf(fptheta2
, "\n");
454 fprintf(fptheta3
, "\n");
457 for (i
= 0; i
< iCA
; i
++)
459 copy_rvec(residuehelixaxis
[i
], residuehelixaxis_tlast
[i
]);
460 copy_rvec(residuevector
[i
], residuevector_tlast
[i
]);
461 copy_rvec(axis3
[i
], axis3_tlast
[i
]);
465 } while (read_next_x(oenv
, status
, &t
, x
, box
));
467 gmx_rmpbc_done(gpbc
);
470 gmx_ffclose(fpcenter
);
472 xvgrclose(fprotation
);
474 gmx_ffclose(fpradius
);
475 gmx_ffclose(fptwist
);
476 gmx_ffclose(fpbending
);
477 gmx_ffclose(fptheta1
);
478 gmx_ffclose(fptheta2
);
479 gmx_ffclose(fptheta3
);