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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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