| 1 | /* | 
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| 2 | *+ | 
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| 3 | *  Name: | 
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| 4 | *     palNutc | 
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| 5 |  | 
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| 6 | *  Purpose: | 
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| 7 | *     Calculate nutation longitude & obliquoty components | 
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| 8 |  | 
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| 9 | *  Language: | 
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| 10 | *     Starlink ANSI C | 
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| 11 |  | 
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| 12 | *  Type of Module: | 
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| 13 | *     Library routine | 
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| 14 |  | 
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| 15 | *  Invocation: | 
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| 16 | *     void palNutc( double date, double * dpsi, double *deps, double *eps0 ); | 
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| 17 |  | 
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| 18 | *  Arguments: | 
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| 19 | *     date = double (Given) | 
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| 20 | *        TT as modified Julian date (JD-2400000.5) | 
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| 21 | *     dpsi = double * (Returned) | 
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| 22 | *        Nutation in longitude | 
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| 23 | *     deps = double * (Returned) | 
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| 24 | *        Nutation in obliquity | 
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| 25 | *     eps0 = double * (Returned) | 
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| 26 | *        Mean obliquity. | 
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| 27 |  | 
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| 28 | *  Description: | 
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| 29 | *     Calculates the longitude * obliquity components and mean obliquity | 
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| 30 | *     using the SOFA/ERFA library. | 
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| 31 |  | 
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| 32 | *  Authors: | 
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| 33 | *     TIMJ: Tim Jenness (JAC, Hawaii) | 
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| 34 | *     {enter_new_authors_here} | 
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| 35 |  | 
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| 36 | *  Notes: | 
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| 37 | *     - Calls eraObl06 and eraNut06a and therefore uses the IAU 206 | 
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| 38 | *       precession/nutation model. | 
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| 39 | *     - Note the change from SLA/F regarding the date. TT is used | 
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| 40 | *       rather than TDB. | 
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| 41 |  | 
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| 42 | *  History: | 
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| 43 | *     2012-03-05 (TIMJ): | 
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| 44 | *        Initial version | 
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| 45 | *        Adapted with permission from the Fortran SLALIB library. | 
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| 46 | *     {enter_further_changes_here} | 
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| 47 |  | 
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| 48 | *  Copyright: | 
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| 49 | *     Copyright (C) 2012 Science and Technology Facilities Council. | 
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| 50 | *     All Rights Reserved. | 
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| 51 |  | 
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| 52 | *  Licence: | 
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| 53 | *     This program is free software; you can redistribute it and/or | 
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| 54 | *     modify it under the terms of the GNU General Public License as | 
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| 55 | *     published by the Free Software Foundation; either version 3 of | 
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| 56 | *     the License, or (at your option) any later version. | 
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| 57 | * | 
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| 58 | *     This program is distributed in the hope that it will be | 
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| 59 | *     useful, but WITHOUT ANY WARRANTY; without even the implied | 
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| 60 | *     warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR | 
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| 61 | *     PURPOSE. See the GNU General Public License for more details. | 
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| 62 | * | 
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| 63 | *     You should have received a copy of the GNU General Public License | 
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| 64 | *     along with this program; if not, write to the Free Software | 
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| 65 | *     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, | 
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| 66 | *     MA 02110-1301, USA. | 
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| 67 |  | 
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| 68 | *  Bugs: | 
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| 69 | *     {note_any_bugs_here} | 
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| 70 | *- | 
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| 71 | */ | 
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| 72 |  | 
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| 73 | #include "pal.h" | 
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| 74 | #include "palmac.h" | 
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| 75 | #include "pal1sofa.h" | 
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| 76 |  | 
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| 77 | void palNutc( double date, double * dpsi, double *deps, double *eps0 ) { | 
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| 78 | eraNut06a( PAL__MJD0, date, dpsi, deps ); | 
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| 79 | *eps0 = eraObl06( PAL__MJD0, date ); | 
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| 80 | } | 
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