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Diffstat (limited to 'ast/erfa/nut06a.c')
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diff --git a/ast/erfa/nut06a.c b/ast/erfa/nut06a.c deleted file mode 100644 index c4d945e..0000000 --- a/ast/erfa/nut06a.c +++ /dev/null @@ -1,162 +0,0 @@ -#include "erfa.h" - -void eraNut06a(double date1, double date2, double *dpsi, double *deps) -/* -** - - - - - - - - - - -** e r a N u t 0 6 a -** - - - - - - - - - - -** -** IAU 2000A nutation with adjustments to match the IAU 2006 -** precession. -** -** Given: -** date1,date2 double TT as a 2-part Julian Date (Note 1) -** -** Returned: -** dpsi,deps double nutation, luni-solar + planetary (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 nutation components in longitude and obliquity are in radians -** and with respect to the mean equinox and ecliptic of date, -** IAU 2006 precession model (Hilton et al. 2006, Capitaine et al. -** 2005). -** -** 3) The function first computes the IAU 2000A nutation, then applies -** adjustments for (i) the consequences of the change in obliquity -** from the IAU 1980 ecliptic to the IAU 2006 ecliptic and (ii) the -** secular variation in the Earth's dynamical form factor J2. -** -** 4) The present function provides classical nutation, complementing -** the IAU 2000 frame bias and IAU 2006 precession. It delivers a -** pole which is at current epochs accurate to a few tens of -** microarcseconds, apart from the free core nutation. -** -** Called: -** eraNut00a nutation, IAU 2000A -** -** References: -** -** Chapront, J., Chapront-Touze, M. & Francou, G. 2002, -** Astron.Astrophys. 387, 700 -** -** Lieske, J.H., Lederle, T., Fricke, W. & Morando, B. 1977, -** Astron.Astrophys. 58, 1-16 -** -** Mathews, P.M., Herring, T.A., Buffet, B.A. 2002, J.Geophys.Res. -** 107, B4. The MHB_2000 code itself was obtained on 9th September -** 2002 from ftp//maia.usno.navy.mil/conv2000/chapter5/IAU2000A. -** -** Simon, J.-L., Bretagnon, P., Chapront, J., Chapront-Touze, M., -** Francou, G., Laskar, J. 1994, Astron.Astrophys. 282, 663-683 -** -** Souchay, J., Loysel, B., Kinoshita, H., Folgueira, M. 1999, -** Astron.Astrophys.Supp.Ser. 135, 111 -** -** Wallace, P.T., "Software for Implementing the IAU 2000 -** Resolutions", in IERS Workshop 5.1 (2002) -** -** Copyright (C) 2013-2016, NumFOCUS Foundation. -** Derived, with permission, from the SOFA library. See notes at end of file. -*/ -{ - double t, fj2, dp, de; - - -/* Interval between fundamental date J2000.0 and given date (JC). */ - t = ((date1 - ERFA_DJ00) + date2) / ERFA_DJC; - -/* Factor correcting for secular variation of J2. */ - fj2 = -2.7774e-6 * t; - -/* Obtain IAU 2000A nutation. */ - eraNut00a(date1, date2, &dp, &de); - -/* Apply P03 adjustments (Wallace & Capitaine, 2006, Eqs.5). */ - *dpsi = dp + dp * (0.4697e-6 + fj2); - *deps = de + de * fj2; - - 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. -** -*/ |