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Diffstat (limited to 'ast/erfa/eect00.c')
| -rw-r--r-- | ast/erfa/eect00.c | 291 |
1 files changed, 0 insertions, 291 deletions
diff --git a/ast/erfa/eect00.c b/ast/erfa/eect00.c deleted file mode 100644 index b8e4bf3..0000000 --- a/ast/erfa/eect00.c +++ /dev/null @@ -1,291 +0,0 @@ -#include "erfa.h" - -double eraEect00(double date1, double date2) -/* -** - - - - - - - - - - -** e r a E e c t 0 0 -** - - - - - - - - - - -** -** Equation of the equinoxes complementary terms, consistent with -** IAU 2000 resolutions. -** -** Given: -** date1,date2 double TT as a 2-part Julian Date (Note 1) -** -** Returned (function value): -** double complementary terms (Note 2) -** -** 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) The "complementary terms" are part of the equation of the -** equinoxes (EE), classically the difference between apparent and -** mean Sidereal Time: -** -** GAST = GMST + EE -** -** with: -** -** EE = dpsi * cos(eps) -** -** where dpsi is the nutation in longitude and eps is the obliquity -** of date. However, if the rotation of the Earth were constant in -** an inertial frame the classical formulation would lead to -** apparent irregularities in the UT1 timescale traceable to side- -** effects of precession-nutation. In order to eliminate these -** effects from UT1, "complementary terms" were introduced in 1994 -** (IAU, 1994) and took effect from 1997 (Capitaine and Gontier, -** 1993): -** -** GAST = GMST + CT + EE -** -** By convention, the complementary terms are included as part of -** the equation of the equinoxes rather than as part of the mean -** Sidereal Time. This slightly compromises the "geometrical" -** interpretation of mean sidereal time but is otherwise -** inconsequential. -** -** The present function computes CT in the above expression, -** compatible with IAU 2000 resolutions (Capitaine et al., 2002, and -** IERS Conventions 2003). -** -** Called: -** eraFal03 mean anomaly of the Moon -** eraFalp03 mean anomaly of the Sun -** eraFaf03 mean argument of the latitude of the Moon -** eraFad03 mean elongation of the Moon from the Sun -** eraFaom03 mean longitude of the Moon's ascending node -** eraFave03 mean longitude of Venus -** eraFae03 mean longitude of Earth -** eraFapa03 general accumulated precession in longitude -** -** References: -** -** Capitaine, N. & Gontier, A.-M., Astron. Astrophys., 275, -** 645-650 (1993) -** -** Capitaine, N., Wallace, P.T. and McCarthy, D.D., "Expressions to -** implement the IAU 2000 definition of UT1", Astronomy & -** Astrophysics, 406, 1135-1149 (2003) -** -** IAU Resolution C7, Recommendation 3 (1994) -** -** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003), -** IERS Technical Note No. 32, BKG (2004) -** -** Copyright (C) 2013-2016, NumFOCUS Foundation. -** Derived, with permission, from the SOFA library. See notes at end of file. -*/ -{ -/* Time since J2000.0, in Julian centuries */ - double t; - -/* Miscellaneous */ - int i, j; - double a, s0, s1; - -/* Fundamental arguments */ - double fa[14]; - -/* Returned value. */ - double eect; - -/* ----------------------------------------- */ -/* The series for the EE complementary terms */ -/* ----------------------------------------- */ - - typedef struct { - int nfa[8]; /* coefficients of l,l',F,D,Om,LVe,LE,pA */ - double s, c; /* sine and cosine coefficients */ - } TERM; - -/* Terms of order t^0 */ - static const TERM e0[] = { - - /* 1-10 */ - {{ 0, 0, 0, 0, 1, 0, 0, 0}, 2640.96e-6, -0.39e-6 }, - {{ 0, 0, 0, 0, 2, 0, 0, 0}, 63.52e-6, -0.02e-6 }, - {{ 0, 0, 2, -2, 3, 0, 0, 0}, 11.75e-6, 0.01e-6 }, - {{ 0, 0, 2, -2, 1, 0, 0, 0}, 11.21e-6, 0.01e-6 }, - {{ 0, 0, 2, -2, 2, 0, 0, 0}, -4.55e-6, 0.00e-6 }, - {{ 0, 0, 2, 0, 3, 0, 0, 0}, 2.02e-6, 0.00e-6 }, - {{ 0, 0, 2, 0, 1, 0, 0, 0}, 1.98e-6, 0.00e-6 }, - {{ 0, 0, 0, 0, 3, 0, 0, 0}, -1.72e-6, 0.00e-6 }, - {{ 0, 1, 0, 0, 1, 0, 0, 0}, -1.41e-6, -0.01e-6 }, - {{ 0, 1, 0, 0, -1, 0, 0, 0}, -1.26e-6, -0.01e-6 }, - - /* 11-20 */ - {{ 1, 0, 0, 0, -1, 0, 0, 0}, -0.63e-6, 0.00e-6 }, - {{ 1, 0, 0, 0, 1, 0, 0, 0}, -0.63e-6, 0.00e-6 }, - {{ 0, 1, 2, -2, 3, 0, 0, 0}, 0.46e-6, 0.00e-6 }, - {{ 0, 1, 2, -2, 1, 0, 0, 0}, 0.45e-6, 0.00e-6 }, - {{ 0, 0, 4, -4, 4, 0, 0, 0}, 0.36e-6, 0.00e-6 }, - {{ 0, 0, 1, -1, 1, -8, 12, 0}, -0.24e-6, -0.12e-6 }, - {{ 0, 0, 2, 0, 0, 0, 0, 0}, 0.32e-6, 0.00e-6 }, - {{ 0, 0, 2, 0, 2, 0, 0, 0}, 0.28e-6, 0.00e-6 }, - {{ 1, 0, 2, 0, 3, 0, 0, 0}, 0.27e-6, 0.00e-6 }, - {{ 1, 0, 2, 0, 1, 0, 0, 0}, 0.26e-6, 0.00e-6 }, - - /* 21-30 */ - {{ 0, 0, 2, -2, 0, 0, 0, 0}, -0.21e-6, 0.00e-6 }, - {{ 0, 1, -2, 2, -3, 0, 0, 0}, 0.19e-6, 0.00e-6 }, - {{ 0, 1, -2, 2, -1, 0, 0, 0}, 0.18e-6, 0.00e-6 }, - {{ 0, 0, 0, 0, 0, 8,-13, -1}, -0.10e-6, 0.05e-6 }, - {{ 0, 0, 0, 2, 0, 0, 0, 0}, 0.15e-6, 0.00e-6 }, - {{ 2, 0, -2, 0, -1, 0, 0, 0}, -0.14e-6, 0.00e-6 }, - {{ 1, 0, 0, -2, 1, 0, 0, 0}, 0.14e-6, 0.00e-6 }, - {{ 0, 1, 2, -2, 2, 0, 0, 0}, -0.14e-6, 0.00e-6 }, - {{ 1, 0, 0, -2, -1, 0, 0, 0}, 0.14e-6, 0.00e-6 }, - {{ 0, 0, 4, -2, 4, 0, 0, 0}, 0.13e-6, 0.00e-6 }, - - /* 31-33 */ - {{ 0, 0, 2, -2, 4, 0, 0, 0}, -0.11e-6, 0.00e-6 }, - {{ 1, 0, -2, 0, -3, 0, 0, 0}, 0.11e-6, 0.00e-6 }, - {{ 1, 0, -2, 0, -1, 0, 0, 0}, 0.11e-6, 0.00e-6 } - }; - -/* Terms of order t^1 */ - static const TERM e1[] = { - {{ 0, 0, 0, 0, 1, 0, 0, 0}, -0.87e-6, 0.00e-6 } - }; - -/* Number of terms in the series */ - const int NE0 = (int) (sizeof e0 / sizeof (TERM)); - const int NE1 = (int) (sizeof e1 / sizeof (TERM)); - -/*--------------------------------------------------------------------*/ - -/* Interval between fundamental epoch J2000.0 and current date (JC). */ - t = ((date1 - ERFA_DJ00) + date2) / ERFA_DJC; - -/* Fundamental Arguments (from IERS Conventions 2003) */ - -/* Mean anomaly of the Moon. */ - fa[0] = eraFal03(t); - -/* Mean anomaly of the Sun. */ - fa[1] = eraFalp03(t); - -/* Mean longitude of the Moon minus that of the ascending node. */ - fa[2] = eraFaf03(t); - -/* Mean elongation of the Moon from the Sun. */ - fa[3] = eraFad03(t); - -/* Mean longitude of the ascending node of the Moon. */ - fa[4] = eraFaom03(t); - -/* Mean longitude of Venus. */ - fa[5] = eraFave03(t); - -/* Mean longitude of Earth. */ - fa[6] = eraFae03(t); - -/* General precession in longitude. */ - fa[7] = eraFapa03(t); - -/* Evaluate the EE complementary terms. */ - s0 = 0.0; - s1 = 0.0; - - for (i = NE0-1; i >= 0; i--) { - a = 0.0; - for (j = 0; j < 8; j++) { - a += (double)(e0[i].nfa[j]) * fa[j]; - } - s0 += e0[i].s * sin(a) + e0[i].c * cos(a); - } - - for (i = NE1-1; i >= 0; i--) { - a = 0.0; - for (j = 0; j < 8; j++) { - a += (double)(e1[i].nfa[j]) * fa[j]; - } - s1 += e1[i].s * sin(a) + e1[i].c * cos(a); - } - - eect = (s0 + s1 * t ) * ERFA_DAS2R; - - return eect; - -} -/*---------------------------------------------------------------------- -** -** -** 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. -** -*/ |