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#include "erfa.h"
void eraP06e(double date1, double date2,
double *eps0, double *psia, double *oma, double *bpa,
double *bqa, double *pia, double *bpia,
double *epsa, double *chia, double *za, double *zetaa,
double *thetaa, double *pa,
double *gam, double *phi, double *psi)
/*
** - - - - - - - -
** e r a P 0 6 e
** - - - - - - - -
**
** Precession angles, IAU 2006, equinox based.
**
** Given:
** date1,date2 double TT as a 2-part Julian Date (Note 1)
**
** Returned (see Note 2):
** eps0 double epsilon_0
** psia double psi_A
** oma double omega_A
** bpa double P_A
** bqa double Q_A
** pia double pi_A
** bpia double Pi_A
** epsa double obliquity epsilon_A
** chia double chi_A
** za double z_A
** zetaa double zeta_A
** thetaa double theta_A
** pa double p_A
** gam double F-W angle gamma_J2000
** phi double F-W angle phi_J2000
** psi double F-W angle psi_J2000
**
** Notes:
**
** 1) The TT date date1+date2 is a Julian Date, apportioned in any
** convenient way between the two arguments. For example,
** JD(TT)=2450123.7 could be expressed in any of these ways,
** among others:
**
** date1 date2
**
** 2450123.7 0.0 (JD method)
** 2451545.0 -1421.3 (J2000 method)
** 2400000.5 50123.2 (MJD method)
** 2450123.5 0.2 (date & time method)
**
** The JD method is the most natural and convenient to use in
** cases where the loss of several decimal digits of resolution
** is acceptable. The J2000 method is best matched to the way
** the argument is handled internally and will deliver the
** optimum resolution. The MJD method and the date & time methods
** are both good compromises between resolution and convenience.
**
** 2) This function returns the set of equinox based angles for the
** Capitaine et al. "P03" precession theory, adopted by the IAU in
** 2006. The angles are set out in Table 1 of Hilton et al. (2006):
**
** eps0 epsilon_0 obliquity at J2000.0
** psia psi_A luni-solar precession
** oma omega_A inclination of equator wrt J2000.0 ecliptic
** bpa P_A ecliptic pole x, J2000.0 ecliptic triad
** bqa Q_A ecliptic pole -y, J2000.0 ecliptic triad
** pia pi_A angle between moving and J2000.0 ecliptics
** bpia Pi_A longitude of ascending node of the ecliptic
** epsa epsilon_A obliquity of the ecliptic
** chia chi_A planetary precession
** za z_A equatorial precession: -3rd 323 Euler angle
** zetaa zeta_A equatorial precession: -1st 323 Euler angle
** thetaa theta_A equatorial precession: 2nd 323 Euler angle
** pa p_A general precession
** gam gamma_J2000 J2000.0 RA difference of ecliptic poles
** phi phi_J2000 J2000.0 codeclination of ecliptic pole
** psi psi_J2000 longitude difference of equator poles, J2000.0
**
** The returned values are all radians.
**
** 3) Hilton et al. (2006) Table 1 also contains angles that depend on
** models distinct from the P03 precession theory itself, namely the
** IAU 2000A frame bias and nutation. The quoted polynomials are
** used in other ERFA functions:
**
** . eraXy06 contains the polynomial parts of the X and Y series.
**
** . eraS06 contains the polynomial part of the s+XY/2 series.
**
** . eraPfw06 implements the series for the Fukushima-Williams
** angles that are with respect to the GCRS pole (i.e. the variants
** that include frame bias).
**
** 4) The IAU resolution stipulated that the choice of parameterization
** was left to the user, and so an IAU compliant precession
** implementation can be constructed using various combinations of
** the angles returned by the present function.
**
** 5) The parameterization used by ERFA is the version of the Fukushima-
** Williams angles that refers directly to the GCRS pole. These
** angles may be calculated by calling the function eraPfw06. ERFA
** also supports the direct computation of the CIP GCRS X,Y by
** series, available by calling eraXy06.
**
** 6) The agreement between the different parameterizations is at the
** 1 microarcsecond level in the present era.
**
** 7) When constructing a precession formulation that refers to the GCRS
** pole rather than the dynamical pole, it may (depending on the
** choice of angles) be necessary to introduce the frame bias
** explicitly.
**
** 8) It is permissible to re-use the same variable in the returned
** arguments. The quantities are stored in the stated order.
**
** Reference:
**
** Hilton, J. et al., 2006, Celest.Mech.Dyn.Astron. 94, 351
**
** Called:
** eraObl06 mean obliquity, IAU 2006
**
** Copyright (C) 2013-2016, NumFOCUS Foundation.
** Derived, with permission, from the SOFA library. See notes at end of file.
*/
{
double t;
/* Interval between fundamental date J2000.0 and given date (JC). */
t = ((date1 - ERFA_DJ00) + date2) / ERFA_DJC;
/* Obliquity at J2000.0. */
*eps0 = 84381.406 * ERFA_DAS2R;
/* Luni-solar precession. */
*psia = ( 5038.481507 +
( -1.0790069 +
( -0.00114045 +
( 0.000132851 +
( -0.0000000951 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
/* Inclination of mean equator with respect to the J2000.0 ecliptic. */
*oma = *eps0 + ( -0.025754 +
( 0.0512623 +
( -0.00772503 +
( -0.000000467 +
( 0.0000003337 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
/* Ecliptic pole x, J2000.0 ecliptic triad. */
*bpa = ( 4.199094 +
( 0.1939873 +
( -0.00022466 +
( -0.000000912 +
( 0.0000000120 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
/* Ecliptic pole -y, J2000.0 ecliptic triad. */
*bqa = ( -46.811015 +
( 0.0510283 +
( 0.00052413 +
( -0.000000646 +
( -0.0000000172 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
/* Angle between moving and J2000.0 ecliptics. */
*pia = ( 46.998973 +
( -0.0334926 +
( -0.00012559 +
( 0.000000113 +
( -0.0000000022 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
/* Longitude of ascending node of the moving ecliptic. */
*bpia = ( 629546.7936 +
( -867.95758 +
( 0.157992 +
( -0.0005371 +
( -0.00004797 +
( 0.000000072 )
* t) * t) * t) * t) * t) * ERFA_DAS2R;
/* Mean obliquity of the ecliptic. */
*epsa = eraObl06(date1, date2);
/* Planetary precession. */
*chia = ( 10.556403 +
( -2.3814292 +
( -0.00121197 +
( 0.000170663 +
( -0.0000000560 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
/* Equatorial precession: minus the third of the 323 Euler angles. */
*za = ( -2.650545 +
( 2306.077181 +
( 1.0927348 +
( 0.01826837 +
( -0.000028596 +
( -0.0000002904 )
* t) * t) * t) * t) * t) * ERFA_DAS2R;
/* Equatorial precession: minus the first of the 323 Euler angles. */
*zetaa = ( 2.650545 +
( 2306.083227 +
( 0.2988499 +
( 0.01801828 +
( -0.000005971 +
( -0.0000003173 )
* t) * t) * t) * t) * t) * ERFA_DAS2R;
/* Equatorial precession: second of the 323 Euler angles. */
*thetaa = ( 2004.191903 +
( -0.4294934 +
( -0.04182264 +
( -0.000007089 +
( -0.0000001274 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
/* General precession. */
*pa = ( 5028.796195 +
( 1.1054348 +
( 0.00007964 +
( -0.000023857 +
( 0.0000000383 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
/* Fukushima-Williams angles for precession. */
*gam = ( 10.556403 +
( 0.4932044 +
( -0.00031238 +
( -0.000002788 +
( 0.0000000260 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
*phi = *eps0 + ( -46.811015 +
( 0.0511269 +
( 0.00053289 +
( -0.000000440 +
( -0.0000000176 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
*psi = ( 5038.481507 +
( 1.5584176 +
( -0.00018522 +
( -0.000026452 +
( -0.0000000148 )
* t) * t) * t) * t) * t * ERFA_DAS2R;
return;
}
/*----------------------------------------------------------------------
**
**
** Copyright (C) 2013-2016, NumFOCUS Foundation.
** All rights reserved.
**
** This library is derived, with permission, from the International
** Astronomical Union's "Standards of Fundamental Astronomy" library,
** available from http://www.iausofa.org.
**
** The ERFA version is intended to retain identical functionality to
** the SOFA library, but made distinct through different function and
** file names, as set out in the SOFA license conditions. The SOFA
** original has a role as a reference standard for the IAU and IERS,
** and consequently redistribution is permitted only in its unaltered
** state. The ERFA version is not subject to this restriction and
** therefore can be included in distributions which do not support the
** concept of "read only" software.
**
** Although the intent is to replicate the SOFA API (other than
** replacement of prefix names) and results (with the exception of
** bugs; any that are discovered will be fixed), SOFA is not
** responsible for any errors found in this version of the library.
**
** If you wish to acknowledge the SOFA heritage, please acknowledge
** that you are using a library derived from SOFA, rather than SOFA
** itself.
**
**
** TERMS AND CONDITIONS
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1 Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
**
** 2 Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
**
** 3 Neither the name of the Standards Of Fundamental Astronomy Board,
** the International Astronomical Union nor the names of its
** contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
** FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
** COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
** BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
** LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
** ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
** POSSIBILITY OF SUCH DAMAGE.
**
*/
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