source: trunk/FACT++/sofa/src/p06e.c@ 18375

Last change on this file since 18375 was 18346, checked in by tbretz, 11 years ago
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1#include "sofa.h"
2
3void iauP06e(double date1, double date2,
4 double *eps0, double *psia, double *oma, double *bpa,
5 double *bqa, double *pia, double *bpia,
6 double *epsa, double *chia, double *za, double *zetaa,
7 double *thetaa, double *pa,
8 double *gam, double *phi, double *psi)
9/*
10** - - - - - - - -
11** i a u P 0 6 e
12** - - - - - - - -
13**
14** Precession angles, IAU 2006, equinox based.
15**
16** This function is part of the International Astronomical Union's
17** SOFA (Standards Of Fundamental Astronomy) software collection.
18**
19** Status: canonical models.
20**
21** Given:
22** date1,date2 double TT as a 2-part Julian Date (Note 1)
23**
24** Returned (see Note 2):
25** eps0 double epsilon_0
26** psia double psi_A
27** oma double omega_A
28** bpa double P_A
29** bqa double Q_A
30** pia double pi_A
31** bpia double Pi_A
32** epsa double obliquity epsilon_A
33** chia double chi_A
34** za double z_A
35** zetaa double zeta_A
36** thetaa double theta_A
37** pa double p_A
38** gam double F-W angle gamma_J2000
39** phi double F-W angle phi_J2000
40** psi double F-W angle psi_J2000
41**
42** Notes:
43**
44** 1) The TT date date1+date2 is a Julian Date, apportioned in any
45** convenient way between the two arguments. For example,
46** JD(TT)=2450123.7 could be expressed in any of these ways,
47** among others:
48**
49** date1 date2
50**
51** 2450123.7 0.0 (JD method)
52** 2451545.0 -1421.3 (J2000 method)
53** 2400000.5 50123.2 (MJD method)
54** 2450123.5 0.2 (date & time method)
55**
56** The JD method is the most natural and convenient to use in
57** cases where the loss of several decimal digits of resolution
58** is acceptable. The J2000 method is best matched to the way
59** the argument is handled internally and will deliver the
60** optimum resolution. The MJD method and the date & time methods
61** are both good compromises between resolution and convenience.
62**
63** 2) This function returns the set of equinox based angles for the
64** Capitaine et al. "P03" precession theory, adopted by the IAU in
65** 2006. The angles are set out in Table 1 of Hilton et al. (2006):
66**
67** eps0 epsilon_0 obliquity at J2000.0
68** psia psi_A luni-solar precession
69** oma omega_A inclination of equator wrt J2000.0 ecliptic
70** bpa P_A ecliptic pole x, J2000.0 ecliptic triad
71** bqa Q_A ecliptic pole -y, J2000.0 ecliptic triad
72** pia pi_A angle between moving and J2000.0 ecliptics
73** bpia Pi_A longitude of ascending node of the ecliptic
74** epsa epsilon_A obliquity of the ecliptic
75** chia chi_A planetary precession
76** za z_A equatorial precession: -3rd 323 Euler angle
77** zetaa zeta_A equatorial precession: -1st 323 Euler angle
78** thetaa theta_A equatorial precession: 2nd 323 Euler angle
79** pa p_A general precession
80** gam gamma_J2000 J2000.0 RA difference of ecliptic poles
81** phi phi_J2000 J2000.0 codeclination of ecliptic pole
82** psi psi_J2000 longitude difference of equator poles, J2000.0
83**
84** The returned values are all radians.
85**
86** 3) Hilton et al. (2006) Table 1 also contains angles that depend on
87** models distinct from the P03 precession theory itself, namely the
88** IAU 2000A frame bias and nutation. The quoted polynomials are
89** used in other SOFA functions:
90**
91** . iauXy06 contains the polynomial parts of the X and Y series.
92**
93** . iauS06 contains the polynomial part of the s+XY/2 series.
94**
95** . iauPfw06 implements the series for the Fukushima-Williams
96** angles that are with respect to the GCRS pole (i.e. the variants
97** that include frame bias).
98**
99** 4) The IAU resolution stipulated that the choice of parameterization
100** was left to the user, and so an IAU compliant precession
101** implementation can be constructed using various combinations of
102** the angles returned by the present function.
103**
104** 5) The parameterization used by SOFA is the version of the Fukushima-
105** Williams angles that refers directly to the GCRS pole. These
106** angles may be calculated by calling the function iauPfw06. SOFA
107** also supports the direct computation of the CIP GCRS X,Y by
108** series, available by calling iauXy06.
109**
110** 6) The agreement between the different parameterizations is at the
111** 1 microarcsecond level in the present era.
112**
113** 7) When constructing a precession formulation that refers to the GCRS
114** pole rather than the dynamical pole, it may (depending on the
115** choice of angles) be necessary to introduce the frame bias
116** explicitly.
117**
118** 8) It is permissible to re-use the same variable in the returned
119** arguments. The quantities are stored in the stated order.
120**
121** Reference:
122**
123** Hilton, J. et al., 2006, Celest.Mech.Dyn.Astron. 94, 351
124**
125** Called:
126** iauObl06 mean obliquity, IAU 2006
127**
128** This revision: 2013 June 18
129**
130** SOFA release 2015-02-09
131**
132** Copyright (C) 2015 IAU SOFA Board. See notes at end.
133*/
134{
135 double t;
136
137/* Interval between fundamental date J2000.0 and given date (JC). */
138 t = ((date1 - DJ00) + date2) / DJC;
139
140/* Obliquity at J2000.0. */
141
142 *eps0 = 84381.406 * DAS2R;
143
144/* Luni-solar precession. */
145
146 *psia = ( 5038.481507 +
147 ( -1.0790069 +
148 ( -0.00114045 +
149 ( 0.000132851 +
150 ( -0.0000000951 )
151 * t) * t) * t) * t) * t * DAS2R;
152
153/* Inclination of mean equator with respect to the J2000.0 ecliptic. */
154
155 *oma = *eps0 + ( -0.025754 +
156 ( 0.0512623 +
157 ( -0.00772503 +
158 ( -0.000000467 +
159 ( 0.0000003337 )
160 * t) * t) * t) * t) * t * DAS2R;
161
162/* Ecliptic pole x, J2000.0 ecliptic triad. */
163
164 *bpa = ( 4.199094 +
165 ( 0.1939873 +
166 ( -0.00022466 +
167 ( -0.000000912 +
168 ( 0.0000000120 )
169 * t) * t) * t) * t) * t * DAS2R;
170
171/* Ecliptic pole -y, J2000.0 ecliptic triad. */
172
173 *bqa = ( -46.811015 +
174 ( 0.0510283 +
175 ( 0.00052413 +
176 ( -0.000000646 +
177 ( -0.0000000172 )
178 * t) * t) * t) * t) * t * DAS2R;
179
180/* Angle between moving and J2000.0 ecliptics. */
181
182 *pia = ( 46.998973 +
183 ( -0.0334926 +
184 ( -0.00012559 +
185 ( 0.000000113 +
186 ( -0.0000000022 )
187 * t) * t) * t) * t) * t * DAS2R;
188
189/* Longitude of ascending node of the moving ecliptic. */
190
191 *bpia = ( 629546.7936 +
192 ( -867.95758 +
193 ( 0.157992 +
194 ( -0.0005371 +
195 ( -0.00004797 +
196 ( 0.000000072 )
197 * t) * t) * t) * t) * t) * DAS2R;
198
199/* Mean obliquity of the ecliptic. */
200
201 *epsa = iauObl06(date1, date2);
202
203/* Planetary precession. */
204
205 *chia = ( 10.556403 +
206 ( -2.3814292 +
207 ( -0.00121197 +
208 ( 0.000170663 +
209 ( -0.0000000560 )
210 * t) * t) * t) * t) * t * DAS2R;
211
212/* Equatorial precession: minus the third of the 323 Euler angles. */
213
214 *za = ( -2.650545 +
215 ( 2306.077181 +
216 ( 1.0927348 +
217 ( 0.01826837 +
218 ( -0.000028596 +
219 ( -0.0000002904 )
220 * t) * t) * t) * t) * t) * DAS2R;
221
222/* Equatorial precession: minus the first of the 323 Euler angles. */
223
224 *zetaa = ( 2.650545 +
225 ( 2306.083227 +
226 ( 0.2988499 +
227 ( 0.01801828 +
228 ( -0.000005971 +
229 ( -0.0000003173 )
230 * t) * t) * t) * t) * t) * DAS2R;
231
232/* Equatorial precession: second of the 323 Euler angles. */
233
234 *thetaa = ( 2004.191903 +
235 ( -0.4294934 +
236 ( -0.04182264 +
237 ( -0.000007089 +
238 ( -0.0000001274 )
239 * t) * t) * t) * t) * t * DAS2R;
240
241/* General precession. */
242
243 *pa = ( 5028.796195 +
244 ( 1.1054348 +
245 ( 0.00007964 +
246 ( -0.000023857 +
247 ( 0.0000000383 )
248 * t) * t) * t) * t) * t * DAS2R;
249
250/* Fukushima-Williams angles for precession. */
251
252 *gam = ( 10.556403 +
253 ( 0.4932044 +
254 ( -0.00031238 +
255 ( -0.000002788 +
256 ( 0.0000000260 )
257 * t) * t) * t) * t) * t * DAS2R;
258
259 *phi = *eps0 + ( -46.811015 +
260 ( 0.0511269 +
261 ( 0.00053289 +
262 ( -0.000000440 +
263 ( -0.0000000176 )
264 * t) * t) * t) * t) * t * DAS2R;
265
266 *psi = ( 5038.481507 +
267 ( 1.5584176 +
268 ( -0.00018522 +
269 ( -0.000026452 +
270 ( -0.0000000148 )
271 * t) * t) * t) * t) * t * DAS2R;
272
273 return;
274
275/*----------------------------------------------------------------------
276**
277** Copyright (C) 2015
278** Standards Of Fundamental Astronomy Board
279** of the International Astronomical Union.
280**
281** =====================
282** SOFA Software License
283** =====================
284**
285** NOTICE TO USER:
286**
287** BY USING THIS SOFTWARE YOU ACCEPT THE FOLLOWING SIX TERMS AND
288** CONDITIONS WHICH APPLY TO ITS USE.
289**
290** 1. The Software is owned by the IAU SOFA Board ("SOFA").
291**
292** 2. Permission is granted to anyone to use the SOFA software for any
293** purpose, including commercial applications, free of charge and
294** without payment of royalties, subject to the conditions and
295** restrictions listed below.
296**
297** 3. You (the user) may copy and distribute SOFA source code to others,
298** and use and adapt its code and algorithms in your own software,
299** on a world-wide, royalty-free basis. That portion of your
300** distribution that does not consist of intact and unchanged copies
301** of SOFA source code files is a "derived work" that must comply
302** with the following requirements:
303**
304** a) Your work shall be marked or carry a statement that it
305** (i) uses routines and computations derived by you from
306** software provided by SOFA under license to you; and
307** (ii) does not itself constitute software provided by and/or
308** endorsed by SOFA.
309**
310** b) The source code of your derived work must contain descriptions
311** of how the derived work is based upon, contains and/or differs
312** from the original SOFA software.
313**
314** c) The names of all routines in your derived work shall not
315** include the prefix "iau" or "sofa" or trivial modifications
316** thereof such as changes of case.
317**
318** d) The origin of the SOFA components of your derived work must
319** not be misrepresented; you must not claim that you wrote the
320** original software, nor file a patent application for SOFA
321** software or algorithms embedded in the SOFA software.
322**
323** e) These requirements must be reproduced intact in any source
324** distribution and shall apply to anyone to whom you have
325** granted a further right to modify the source code of your
326** derived work.
327**
328** Note that, as originally distributed, the SOFA software is
329** intended to be a definitive implementation of the IAU standards,
330** and consequently third-party modifications are discouraged. All
331** variations, no matter how minor, must be explicitly marked as
332** such, as explained above.
333**
334** 4. You shall not cause the SOFA software to be brought into
335** disrepute, either by misuse, or use for inappropriate tasks, or
336** by inappropriate modification.
337**
338** 5. The SOFA software is provided "as is" and SOFA makes no warranty
339** as to its use or performance. SOFA does not and cannot warrant
340** the performance or results which the user may obtain by using the
341** SOFA software. SOFA makes no warranties, express or implied, as
342** to non-infringement of third party rights, merchantability, or
343** fitness for any particular purpose. In no event will SOFA be
344** liable to the user for any consequential, incidental, or special
345** damages, including any lost profits or lost savings, even if a
346** SOFA representative has been advised of such damages, or for any
347** claim by any third party.
348**
349** 6. The provision of any version of the SOFA software under the terms
350** and conditions specified herein does not imply that future
351** versions will also be made available under the same terms and
352** conditions.
353*
354** In any published work or commercial product which uses the SOFA
355** software directly, acknowledgement (see www.iausofa.org) is
356** appreciated.
357**
358** Correspondence concerning SOFA software should be addressed as
359** follows:
360**
361** By email: sofa@ukho.gov.uk
362** By post: IAU SOFA Center
363** HM Nautical Almanac Office
364** UK Hydrographic Office
365** Admiralty Way, Taunton
366** Somerset, TA1 2DN
367** United Kingdom
368**
369**--------------------------------------------------------------------*/
370}
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