SUBROUTINE iau_D2TF ( NDP, DAYS, SIGN, IHMSF ) *+ * - - - - - - - - - * i a u _ D 2 T F * - - - - - - - - - * * Decompose days to hours, minutes, seconds, fraction. * * This routine is part of the International Astronomical Union's * SOFA (Standards of Fundamental Astronomy) software collection. * * Status: vector/matrix support routine. * * Given: * NDP i resolution (Note 1) * DAYS d interval in days * * Returned: * SIGN c '+' or '-' * IHMSF i(4) hours, minutes, seconds, fraction * * Notes: * * 1) NDP is interpreted as follows: * * NDP resolution * : ...0000 00 00 * -7 1000 00 00 * -6 100 00 00 * -5 10 00 00 * -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 * : 0 00 00.000... * * 2) The largest positive useful value for NDP is determined by the * size of DAYS, the format of DOUBLE PRECISION floating-point * numbers on the target platform, and the risk of overflowing * IHMSF(4). On a typical platform, for DAYS up to 1D0, the * available floating-point precision might correspond to NDP=12. * However, the practical limit is typically NDP=9, set by the * capacity of a 32-bit IHMSF(4). * * 3) The absolute value of DAYS may exceed 1D0. In cases where it * does not, it is up to the caller to test for and handle the * case where DAYS is very nearly 1D0 and rounds up to 24 hours, * by testing for IHMSF(1)=24 and setting IHMSF(1-4) to zero. * * This revision: 2005 August 26 * * SOFA release 2021-05-12 * * Copyright (C) 2021 IAU SOFA Board. See notes at end. * *----------------------------------------------------------------------- IMPLICIT NONE INTEGER NDP DOUBLE PRECISION DAYS CHARACTER SIGN*(*) INTEGER IHMSF(4) * Days to seconds DOUBLE PRECISION D2S PARAMETER ( D2S = 86400D0 ) INTEGER NRS, N DOUBLE PRECISION RS, RM, RH, A, AH, AM, AS, AF * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - * Handle sign. IF ( DAYS .GE. 0D0 ) THEN SIGN = '+' ELSE SIGN = '-' END IF * Interval in seconds. A = D2S * ABS(DAYS) * Pre-round if resolution coarser than 1 second (then pretend NDP=1). IF ( NDP .LT. 0 ) THEN NRS = 1 DO 1 N=1,-NDP IF ( N.EQ.2 .OR. N.EQ.4 ) THEN NRS = NRS * 6 ELSE NRS = NRS * 10 END IF 1 CONTINUE RS = DBLE(NRS) A = RS * ANINT(A/RS) END IF * Express the unit of each field in resolution units. NRS = 1 DO 2 N=1,NDP NRS = NRS * 10 2 CONTINUE RS = DBLE(NRS) RM = RS * 60D0 RH = RM * 60D0 * Round the interval and express in resolution units. A = ANINT(RS*A) * Break into fields. AH = AINT(A/RH) A = A - AH*RH AM = AINT(A/RM) A = A - AM*RM AS = AINT(A/RS) AF = A - AS*RS * Return results. IHMSF(1) = NINT(AH) IHMSF(2) = NINT(AM) IHMSF(3) = NINT(AS) IHMSF(4) = NINT(AF) * Finished. *+---------------------------------------------------------------------- * * Copyright (C) 2021 * Standards Of Fundamental Astronomy Board * of the International Astronomical Union. * * ===================== * SOFA Software License * ===================== * * NOTICE TO USER: * * BY USING THIS SOFTWARE YOU ACCEPT THE FOLLOWING SIX 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 names of all routines in your derived work shall not * include the prefix "iau" or "sofa" or trivial modifications * thereof such as changes of case. * * 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. You shall not cause the SOFA software to be brought into * disrepute, either by misuse, or use for inappropriate tasks, or * by inappropriate modification. * * 5. 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. * * 6. 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. * * In any published work or commercial product which uses the SOFA * software directly, acknowledgement (see www.iausofa.org) is * appreciated. * * 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 * *----------------------------------------------------------------------- END