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+.help dr2af Jun99 "Slalib Package"
+.nf
+
+      SUBROUTINE slDRAF (NDP, ANGLE, SIGN, IDMSF)
+
+     - - - - - -
+      D R 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:  slDDTF
+
+  P.T.Wallace   Starlink   19 March 1999
+
+  Copyright (C) 1995 Rutherford Appleton Laboratory
+  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.
+
+.fi
+.endhelp