Permalink
Find file
Fetching contributors…
Cannot retrieve contributors at this time
76 lines (68 sloc) 2.37 KB
SUBROUTINE sla_DR2TF (NDP, ANGLE, SIGN, IHMSF)
*+
* - - - - - -
* D R 2 T F
* - - - - - -
*
* Convert an angle in radians to hours, minutes, seconds
* (double precision)
*
* Given:
* NDP i number of decimal places of seconds
* ANGLE d angle in radians
*
* Returned:
* SIGN c '+' or '-'
* IHMSF i(4) hours, minutes, seconds, fraction
*
* Notes:
*
* 1) NDP less than zero is interpreted as zero.
*
* 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 machine, and the risk of overflowing
* IHMSF(4). On some architectures, for ANGLE up to 2pi, the
* available floating-point precision corresponds roughly to
* NDP=12. However, the practical limit is NDP=9, set by the
* capacity of a typical 32-bit IHMSF(4).
*
* 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: sla_DD2TF
*
* Last revision: 26 December 2004
*
* Copyright P.T.Wallace. All rights reserved.
*
* License:
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (see SLA_CONDITIONS); if not, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307 USA
*
*-
IMPLICIT NONE
INTEGER NDP
DOUBLE PRECISION ANGLE
CHARACTER SIGN*(*)
INTEGER IHMSF(4)
* Turns to radians
DOUBLE PRECISION T2R
PARAMETER (T2R=6.283185307179586476925287D0)
* Scale then use days to h,m,s routine
CALL sla_DD2TF(NDP,ANGLE/T2R,SIGN,IHMSF)
END