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.help cr2tf Jun99 "Slalib Package"
.nf

      SUBROUTINE slCRTF (NDP, ANGLE, SIGN, IHMSF)

     - - - - - -
      C R T F
     - - - - - -

  Convert an angle in radians into hours, minutes, seconds
  (single precision)

  Given:
     NDP       int      number of decimal places of seconds
     ANGLE     real     angle in radians

  Returned:
     SIGN      char     '+' or '-'
     IHMSF     int(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 REAL floating-point numbers on the target
      machine, and the risk of overflowing IHMSF(4).  For example,
      on the VAX, for ANGLE up to 2pi, the available floating-point
      precision corresponds roughly to NDP=3.  This is well below
      the ultimate limit of NDP=9 set by the capacity of the 32-bit
      integer 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:  slCDTF

  P.T.Wallace   Starlink   18 March 1999

  Copyright (C) 1999 Rutherford Appleton Laboratory
  Copyright (C) 1995 Association of Universities for Research in Astronomy Inc.

.fi
.endhelp