#include "sofam.h" #include int iauDtf2d(char *scale, int iy, int im, int id, int ihr, int imn, double sec, double *d1, double *d2) /* ** - - - - - - - - - ** i a u D t f 2 d ** - - - - - - - - - ** ** Encode date and time fields into 2-part Julian Date (or in the case ** of UTC a quasi-JD form that includes special provision for leap ** seconds). ** ** This function is part of the International Astronomical Union's ** SOFA (Standards of Fundamental Astronomy) software collection. ** ** Status: support function. ** ** Given: ** scale char[] time scale ID (Note 1) ** iy,im,id int year, month, day in Gregorian calendar (Note 2) ** ihr,imn int hour, minute ** sec double seconds ** ** Returned: ** dj1,dj2 double 2-part Julian Date (Notes 3,4) ** ** Returned (function value): ** int status: +3 = both of next two ** +2 = time is after end of day (Note 5) ** +1 = dubious year (Note 6) ** 0 = OK ** -1 = bad year ** -2 = bad month ** -3 = bad day ** -4 = bad hour ** -5 = bad minute ** -6 = bad second (<0) ** ** Notes: ** ** 1) scale identifies the time scale. Only the value "UTC" (in upper ** case) is significant, and enables handling of leap seconds (see ** Note 4). ** ** 2) For calendar conventions and limitations, see iauCal2jd. ** ** 3) The sum of the results, d1+d2, is Julian Date, where normally d1 ** is the Julian Day Number and d2 is the fraction of a day. In the ** case of UTC, where the use of JD is problematical, special ** conventions apply: see the next note. ** ** 4) JD cannot unambiguously represent UTC during a leap second unless ** special measures are taken. The SOFA internal convention is that ** the quasi-JD day represents UTC days whether the length is 86399, ** 86400 or 86401 SI seconds. ** ** 5) The warning status "time is after end of day" usually means that ** the sec argument is greater than 60.0. However, in a day ending ** in a leap second the limit changes to 61.0 (or 59.0 in the case ** of a negative leap second). ** ** 6) The warning status "dubious year" flags UTCs that predate the ** introduction of the time scale and that are too far in the future ** to be trusted. See iauDat for further details. ** ** 7) Only in the case of continuous and regular time scales (TAI, TT, ** TCG, TCB and TDB) is the result DJ1+DJ2 a Julian Date, strictly ** speaking. In the other cases (UT1 and UTC) the result must be ** used with circumspection; in particular the difference between ** two such results cannot be interpreted as a precise time ** interval. ** ** Called: ** iauCal2jd Gregorian calendar to JD ** iauDat delta(AT) = TAI-UTC ** iauJd2cal JD to Gregorian calendar ** ** This revision: 2010 September 7 ** ** SOFA release 2010-12-01 ** ** Copyright (C) 2010 IAU SOFA Board. See notes at end. */ { int js, iy2, im2, id2; double dj, w, day, seclim, dat1, dat2, ddt, time; /* Today's Julian Day Number. */ js = iauCal2jd(iy, im, id, &dj, &w); if ( js ) return js; dj += w; /* Day length and final minute length in seconds (provisional). */ day = DAYSEC; seclim = 60; /* Deal with the UTC leap second case. */ if ( ! strcmp(scale,"UTC") ) { /* TAI-UTC today. */ js = iauDat(iy, im, id, 0.0, &dat1); if ( js < 0 ) return js; /* TAI-UTC tomorrow. */ js = iauJd2cal ( dj, 1.0, &iy2, &im2, &id2, &w); if ( js ) return js; js = iauDat(iy2, im2, id2, 0.0, &dat2); if ( js < 0 ) return js; /* The change in TAI-UTC (seconds). */ ddt = dat2 - dat1; /* If leap second day, correct the day and final minute lengths. */ if ( fabs(ddt) > 0.5 ) { day += ddt; if ( ihr == 23 && imn == 59 ) seclim += ddt; } } /* Validate the time. */ if ( ihr >= 0 && ihr <= 23 ) { if ( imn >= 0 && imn <= 59 ) { if ( sec >= 0 ) { if ( sec >= seclim ) { js += 2; } } else { js = -6; } } else { js = -5; } } else { js = -4; } if ( js < 0 ) return js; /* The time in days. */ time = ( 60.0 * ( (double) ( 60 * ihr + imn ) ) + sec ) / day; /* Return the date and time. */ *d1 = dj; *d2 = time; /* Status. */ return js; /*---------------------------------------------------------------------- ** ** Copyright (C) 2010 ** Standards Of Fundamental Astronomy Board ** of the International Astronomical Union. ** ** ===================== ** SOFA Software License ** ===================== ** ** NOTICE TO USER: ** ** BY USING THIS SOFTWARE YOU ACCEPT THE FOLLOWING TERMS AND CONDITIONS ** WHICH APPLY TO ITS USE. ** ** 1. The Software is owned by the IAU SOFA Board ("SOFA"). ** ** 2. Permission is granted to anyone to use the SOFA software for any ** purpose, including commercial applications, free of charge and ** without payment of royalties, subject to the conditions and ** restrictions listed below. ** ** 3. You (the user) may copy and distribute SOFA source code to others, ** and use and adapt its code and algorithms in your own software, ** on a world-wide, royalty-free basis. That portion of your ** distribution that does not consist of intact and unchanged copies ** of SOFA source code files is a "derived work" that must comply ** with the following requirements: ** ** a) Your work shall be marked or carry a statement that it ** (i) uses routines and computations derived by you from ** software provided by SOFA under license to you; and ** (ii) does not itself constitute software provided by and/or ** endorsed by SOFA. ** ** b) The source code of your derived work must contain descriptions ** of how the derived work is based upon, contains and/or differs ** from the original SOFA software. ** ** c) The name(s) of all routine(s) in your derived work shall not ** include the prefix "iau". ** ** d) The origin of the SOFA components of your derived work must ** not be misrepresented; you must not claim that you wrote the ** original software, nor file a patent application for SOFA ** software or algorithms embedded in the SOFA software. ** ** e) These requirements must be reproduced intact in any source ** distribution and shall apply to anyone to whom you have ** granted a further right to modify the source code of your ** derived work. ** ** Note that, as originally distributed, the SOFA software is ** intended to be a definitive implementation of the IAU standards, ** and consequently third-party modifications are discouraged. All ** variations, no matter how minor, must be explicitly marked as ** such, as explained above. ** ** 4. In any published work or commercial products which includes ** results achieved by using the SOFA software, you shall ** acknowledge that the SOFA software was used in obtaining those ** results. ** ** 5. You shall not cause the SOFA software to be brought into ** disrepute, either by misuse, or use for inappropriate tasks, or ** by inappropriate modification. ** ** 6. The SOFA software is provided "as is" and SOFA makes no warranty ** as to its use or performance. SOFA does not and cannot warrant ** the performance or results which the user may obtain by using the ** SOFA software. SOFA makes no warranties, express or implied, as ** to non-infringement of third party rights, merchantability, or ** fitness for any particular purpose. In no event will SOFA be ** liable to the user for any consequential, incidental, or special ** damages, including any lost profits or lost savings, even if a ** SOFA representative has been advised of such damages, or for any ** claim by any third party. ** ** 7. The provision of any version of the SOFA software under the terms ** and conditions specified herein does not imply that future ** versions will also be made available under the same terms and ** conditions. ** ** Correspondence concerning SOFA software should be addressed as ** follows: ** ** By email: sofa@ukho.gov.uk ** By post: IAU SOFA Center ** HM Nautical Almanac Office ** UK Hydrographic Office ** Admiralty Way, Taunton ** Somerset, TA1 2DN ** United Kingdom ** **--------------------------------------------------------------------*/ }