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Diffstat (limited to 'ast/erfa/taiutc.c')
| -rw-r--r-- | ast/erfa/taiutc.c | 168 |
1 files changed, 0 insertions, 168 deletions
diff --git a/ast/erfa/taiutc.c b/ast/erfa/taiutc.c deleted file mode 100644 index ce3a177..0000000 --- a/ast/erfa/taiutc.c +++ /dev/null @@ -1,168 +0,0 @@ -#include "erfa.h" - -int eraTaiutc(double tai1, double tai2, double *utc1, double *utc2) -/* -** - - - - - - - - - - -** e r a T a i u t c -** - - - - - - - - - - -** -** Time scale transformation: International Atomic Time, TAI, to -** Coordinated Universal Time, UTC. -** -** Given: -** tai1,tai2 double TAI as a 2-part Julian Date (Note 1) -** -** Returned: -** utc1,utc2 double UTC as a 2-part quasi Julian Date (Notes 1-3) -** -** Returned (function value): -** int status: +1 = dubious year (Note 4) -** 0 = OK -** -1 = unacceptable date -** -** Notes: -** -** 1) tai1+tai2 is Julian Date, apportioned in any convenient way -** between the two arguments, for example where tai1 is the Julian -** Day Number and tai2 is the fraction of a day. The returned utc1 -** and utc2 form an analogous pair, except that a special convention -** is used, to deal with the problem of leap seconds - see the next -** note. -** -** 2) JD cannot unambiguously represent UTC during a leap second unless -** special measures are taken. The convention in the present -** function is that the JD day represents UTC days whether the -** length is 86399, 86400 or 86401 SI seconds. In the 1960-1972 era -** there were smaller jumps (in either direction) each time the -** linear UTC(TAI) expression was changed, and these "mini-leaps" -** are also included in the ERFA convention. -** -** 3) The function eraD2dtf can be used to transform the UTC quasi-JD -** into calendar date and clock time, including UTC leap second -** handling. -** -** 4) The warning status "dubious year" flags UTCs that predate the -** introduction of the time scale or that are too far in the future -** to be trusted. See eraDat for further details. -** -** Called: -** eraUtctai UTC to TAI -** -** References: -** -** McCarthy, D. D., Petit, G. (eds.), IERS Conventions (2003), -** IERS Technical Note No. 32, BKG (2004) -** -** Explanatory Supplement to the Astronomical Almanac, -** P. Kenneth Seidelmann (ed), University Science Books (1992) -** -** Copyright (C) 2013-2016, NumFOCUS Foundation. -** Derived, with permission, from the SOFA library. See notes at end of file. -*/ -{ - int big1; - int i, j; - double a1, a2, u1, u2, g1, g2; - - -/* Put the two parts of the TAI into big-first order. */ - big1 = ( tai1 >= tai2 ); - if ( big1 ) { - a1 = tai1; - a2 = tai2; - } else { - a1 = tai2; - a2 = tai1; - } - -/* Initial guess for UTC. */ - u1 = a1; - u2 = a2; - -/* Iterate (though in most cases just once is enough). */ - for ( i = 0; i < 3; i++ ) { - - /* Guessed UTC to TAI. */ - j = eraUtctai(u1, u2, &g1, &g2); - if ( j < 0 ) return j; - - /* Adjust guessed UTC. */ - u2 += a1 - g1; - u2 += a2 - g2; - } - -/* Return the UTC result, preserving the TAI order. */ - if ( big1 ) { - *utc1 = u1; - *utc2 = u2; - } else { - *utc1 = u2; - *utc2 = u1; - } - -/* Status. */ - return j; - -} -/*---------------------------------------------------------------------- -** -** -** 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. -** -*/ |