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Diffstat (limited to 'ast/erfa/d2dtf.c')
| -rw-r--r-- | ast/erfa/d2dtf.c | 245 |
1 files changed, 0 insertions, 245 deletions
diff --git a/ast/erfa/d2dtf.c b/ast/erfa/d2dtf.c deleted file mode 100644 index 4476970..0000000 --- a/ast/erfa/d2dtf.c +++ /dev/null @@ -1,245 +0,0 @@ -#include "erfa.h" -#include <string.h> - -int eraD2dtf(const char *scale, int ndp, double d1, double d2, - int *iy, int *im, int *id, int ihmsf[4]) -/* -** - - - - - - - - - -** e r a D 2 d t f -** - - - - - - - - - -** -** Format for output a 2-part Julian Date (or in the case of UTC a -** quasi-JD form that includes special provision for leap seconds). -** -** Given: -** scale char[] time scale ID (Note 1) -** ndp int resolution (Note 2) -** d1,d2 double time as a 2-part Julian Date (Notes 3,4) -** -** Returned: -** iy,im,id int year, month, day in Gregorian calendar (Note 5) -** ihmsf int[4] hours, minutes, seconds, fraction (Note 1) -** -** Returned (function value): -** int status: +1 = dubious year (Note 5) -** 0 = OK -** -1 = unacceptable date (Note 6) -** -** 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) ndp is the number of decimal places in the seconds field, and can -** have negative as well as positive values, such as: -** -** ndp resolution -** -4 1 00 00 -** -3 0 10 00 -** -2 0 01 00 -** -1 0 00 10 -** 0 0 00 01 -** 1 0 00 00.1 -** 2 0 00 00.01 -** 3 0 00 00.001 -** -** The limits are platform dependent, but a safe range is -5 to +9. -** -** 3) d1+d2 is Julian Date, apportioned in any convenient way between -** the two arguments, for example where 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 ERFA internal convention is that -** the quasi-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. -** -** 5) 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. -** -** 6) For calendar conventions and limitations, see eraCal2jd. -** -** Called: -** eraJd2cal JD to Gregorian calendar -** eraD2tf decompose days to hms -** eraDat delta(AT) = TAI-UTC -** -** Copyright (C) 2013-2016, NumFOCUS Foundation. -** Derived, with permission, from the SOFA library. See notes at end of file. -*/ -{ - int leap; - char s; - int iy1, im1, id1, js, iy2, im2, id2, ihmsf1[4], i; - double a1, b1, fd, dat0, dat12, w, dat24, dleap; - - -/* The two-part JD. */ - a1 = d1; - b1 = d2; - -/* Provisional calendar date. */ - js = eraJd2cal(a1, b1, &iy1, &im1, &id1, &fd); - if ( js ) return -1; - -/* Is this a leap second day? */ - leap = 0; - if ( ! strcmp(scale,"UTC") ) { - - /* TAI-UTC at 0h today. */ - js = eraDat(iy1, im1, id1, 0.0, &dat0); - if ( js < 0 ) return -1; - - /* TAI-UTC at 12h today (to detect drift). */ - js = eraDat(iy1, im1, id1, 0.5, &dat12); - if ( js < 0 ) return -1; - - /* TAI-UTC at 0h tomorrow (to detect jumps). */ - js = eraJd2cal(a1+1.5, b1-fd, &iy2, &im2, &id2, &w); - if ( js ) return -1; - js = eraDat(iy2, im2, id2, 0.0, &dat24); - if ( js < 0 ) return -1; - - /* Any sudden change in TAI-UTC (seconds). */ - dleap = dat24 - (2.0*dat12 - dat0); - - /* If leap second day, scale the fraction of a day into SI. */ - leap = (dleap != 0.0); - if (leap) fd += fd * dleap/ERFA_DAYSEC; - } - -/* Provisional time of day. */ - eraD2tf ( ndp, fd, &s, ihmsf1 ); - -/* Has the (rounded) time gone past 24h? */ - if ( ihmsf1[0] > 23 ) { - - /* Yes. We probably need tomorrow's calendar date. */ - js = eraJd2cal(a1+1.5, b1-fd, &iy2, &im2, &id2, &w); - if ( js ) return -1; - - /* Is today a leap second day? */ - if ( ! leap ) { - - /* No. Use 0h tomorrow. */ - iy1 = iy2; - im1 = im2; - id1 = id2; - ihmsf1[0] = 0; - ihmsf1[1] = 0; - ihmsf1[2] = 0; - - } else { - - /* Yes. Are we past the leap second itself? */ - if ( ihmsf1[2] > 0 ) { - - /* Yes. Use tomorrow but allow for the leap second. */ - iy1 = iy2; - im1 = im2; - id1 = id2; - ihmsf1[0] = 0; - ihmsf1[1] = 0; - ihmsf1[2] = 0; - - } else { - - /* No. Use 23 59 60... today. */ - ihmsf1[0] = 23; - ihmsf1[1] = 59; - ihmsf1[2] = 60; - } - - /* If rounding to 10s or coarser always go up to new day. */ - if ( ndp < 0 && ihmsf1[2] == 60 ) { - iy1 = iy2; - im1 = im2; - id1 = id2; - ihmsf1[0] = 0; - ihmsf1[1] = 0; - ihmsf1[2] = 0; - } - } - } - -/* Results. */ - *iy = iy1; - *im = im1; - *id = id1; - for ( i = 0; i < 4; i++ ) { - ihmsf[i] = ihmsf1[i]; - } - -/* Status. */ - return js; - -} -/*---------------------------------------------------------------------- -** -** -** 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. -** -*/ |