/* *+ * Name: * palDtt * Purpose: * Return offset between UTC and TT * Language: * Starlink ANSI C * Type of Module: * Library routine * Invocation: * dtt = palDtt( double utc ); * Arguments: * utc = double (Given) * UTC date as a modified JD (JD-2400000.5) * Returned Value: * dtt = double * TT-UTC in seconds * Description: * Increment to be applied to Coordinated Universal Time UTC to give * Terrestrial Time TT (formerly Ephemeris Time ET) * Authors: * TIMJ: Tim Jenness (JAC, Hawaii) * PTW: Patrick T. Wallace * {enter_new_authors_here} * Notes: * - Consider a comprehensive upgrade to use the time transformations in SOFA's time * cookbook: http://www.iausofa.org/sofa_ts_c.pdf. * - See eraDat for a description of error conditions when calling this function * with a time outside of the UTC range. This behaviour differs from slaDtt. * History: * 2012-02-08 (TIMJ): * Initial version * Adapted with permission from the Fortran SLALIB library. * {enter_further_changes_here} * Copyright: * Copyright (C) 1995 Rutherford Appleton Laboratory * Copyright (C) 2012 Science and Technology Facilities Council. * All Rights Reserved. * Licence: * This program is free software: you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation, either * version 3 of the License, or (at your option) any later * version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General * License along with this program. If not, see * . * Bugs: * {note_any_bugs_here} *- */ #include "pal.h" double palDtt( double utc ) { return 32.184 + palDat( utc ); }