SUBROUTINE iau_A2TF ( NDP, ANGLE, SIGN, IHMSF ) *+ * - - - - - - - - - * i a u _ A 2 T F * - - - - - - - - - * * Decompose radians into 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) * ANGLE d angle in radians * * 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 useful value for NDP is determined by the size * of ANGLE, the format of DOUBLE PRECISION floating-point numbers * on the target platform, and the risk of overflowing IHMSF(4). * On a typical platform, for ANGLE up to 2pi, 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 INTEGER, or NDP=4 if INTEGER is only 16 bits. * * 3) The absolute value of ANGLE may exceed 2pi. In cases where it * does not, it is up to the caller to test for and handle the * case where ANGLE is very nearly 2pi and rounds up to 24 hours, * by testing for IHMSF(1)=24 and setting IHMSF(1-4) to zero. * * Called: * iau_D2TF decompose days to hms * * This revision: 2023 April 18 * * SOFA release 2023-10-11 * * Copyright (C) 2023 IAU SOFA Board. See notes at end. * *----------------------------------------------------------------------- IMPLICIT NONE INTEGER NDP DOUBLE PRECISION ANGLE CHARACTER SIGN*(*) INTEGER IHMSF(4) * 2Pi DOUBLE PRECISION D2PI PARAMETER ( D2PI = 6.283185307179586476925287D0 ) * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - * Scale then use days to h,m,s routine. CALL iau_D2TF ( NDP, ANGLE/D2PI, SIGN, IHMSF ) * Finished. *+---------------------------------------------------------------------- * * Copyright (C) 2023 * 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. 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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