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Diffstat (limited to 'ast/erfa/utctai.c')
| -rw-r--r-- | ast/erfa/utctai.c | 186 |
1 files changed, 0 insertions, 186 deletions
diff --git a/ast/erfa/utctai.c b/ast/erfa/utctai.c deleted file mode 100644 index 2863867..0000000 --- a/ast/erfa/utctai.c +++ /dev/null @@ -1,186 +0,0 @@ -#include "erfa.h" - -int eraUtctai(double utc1, double utc2, double *tai1, double *tai2) -/* -** - - - - - - - - - - -** e r a U t c t a i -** - - - - - - - - - - -** -** Time scale transformation: Coordinated Universal Time, UTC, to -** International Atomic Time, TAI. -** -** Given: -** utc1,utc2 double UTC as a 2-part quasi Julian Date (Notes 1-4) -** -** Returned: -** tai1,tai2 double TAI as a 2-part Julian Date (Note 5) -** -** Returned (function value): -** int status: +1 = dubious year (Note 3) -** 0 = OK -** -1 = unacceptable date -** -** Notes: -** -** 1) utc1+utc2 is quasi Julian Date (see Note 2), apportioned in any -** convenient way between the two arguments, for example where utc1 -** is the Julian Day Number and utc2 is the fraction of a day. -** -** 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 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. -** -** 4) The function eraDtf2d converts from calendar date and time of day -** into 2-part Julian Date, and in the case of UTC implements the -** leap-second-ambiguity convention described above. -** -** 5) The returned TAI1,TAI2 are such that their sum is the TAI Julian -** Date. -** -** Called: -** eraJd2cal JD to Gregorian calendar -** eraDat delta(AT) = TAI-UTC -** eraCal2jd Gregorian calendar to JD -** -** 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 iy, im, id, j, iyt, imt, idt; - double u1, u2, fd, dat0, dat12, w, dat24, dlod, dleap, z1, z2, a2; - - -/* Put the two parts of the UTC into big-first order. */ - big1 = ( utc1 >= utc2 ); - if ( big1 ) { - u1 = utc1; - u2 = utc2; - } else { - u1 = utc2; - u2 = utc1; - } - -/* Get TAI-UTC at 0h today. */ - j = eraJd2cal(u1, u2, &iy, &im, &id, &fd); - if ( j ) return j; - j = eraDat(iy, im, id, 0.0, &dat0); - if ( j < 0 ) return j; - -/* Get TAI-UTC at 12h today (to detect drift). */ - j = eraDat(iy, im, id, 0.5, &dat12); - if ( j < 0 ) return j; - -/* Get TAI-UTC at 0h tomorrow (to detect jumps). */ - j = eraJd2cal(u1+1.5, u2-fd, &iyt, &imt, &idt, &w); - if ( j ) return j; - j = eraDat(iyt, imt, idt, 0.0, &dat24); - if ( j < 0 ) return j; - -/* Separate TAI-UTC change into per-day (DLOD) and any jump (DLEAP). */ - dlod = 2.0 * (dat12 - dat0); - dleap = dat24 - (dat0 + dlod); - -/* Remove any scaling applied to spread leap into preceding day. */ - fd *= (ERFA_DAYSEC+dleap)/ERFA_DAYSEC; - -/* Scale from (pre-1972) UTC seconds to SI seconds. */ - fd *= (ERFA_DAYSEC+dlod)/ERFA_DAYSEC; - -/* Today's calendar date to 2-part JD. */ - if ( eraCal2jd(iy, im, id, &z1, &z2) ) return -1; - -/* Assemble the TAI result, preserving the UTC split and order. */ - a2 = z1 - u1; - a2 += z2; - a2 += fd + dat0/ERFA_DAYSEC; - if ( big1 ) { - *tai1 = u1; - *tai2 = a2; - } else { - *tai1 = a2; - *tai2 = 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. -** -*/ |