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SUBROUTINE sla_DR2AF (NDP, ANGLE, SIGN, IDMSF)
*+
* - - - - - -
* D R 2 A F
* - - - - - -
*
* Convert an angle in radians to degrees, arcminutes, arcseconds
* (double precision)
*
* Given:
* NDP i number of decimal places of arcseconds
* ANGLE d angle in radians
*
* Returned:
* SIGN c '+' or '-'
* IDMSF i(4) degrees, arcminutes, arcseconds, 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
* IDMSF(4). For example, on the VAX, 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 the 32-bit integer IDMSF(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 360 deg,
* by testing for IDMSF(1)=360 and setting IDMSF(1-4) to zero.
*
* Called: sla_DD2TF
*
* P.T.Wallace Starlink 19 March 1999
*
* Copyright (C) 1995 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
INTEGER NDP
DOUBLE PRECISION ANGLE
CHARACTER SIGN*(*)
INTEGER IDMSF(4)
* Hours to degrees * radians to turns
DOUBLE PRECISION F
PARAMETER (F=15D0/6.283185307179586476925287D0)
* Scale then use days to h,m,s routine
CALL sla_DD2TF(NDP,ANGLE*F,SIGN,IDMSF)
END
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