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.help cd2tf Jun99 "Slalib Package"
.nf

      SUBROUTINE slCDTF (NDP, DAYS, SIGN, IHMSF)

     - - - - - -
      C D T F
     - - - - - -

  Convert an interval in days into hours, minutes, seconds

  (single precision)

  Given:
     NDP       int      number of decimal places of seconds
     DAYS      real     interval in days

  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
         DAYS, the format of REAL floating-point numbers on the target
         machine, and the risk of overflowing IHMSF(4).  For example,
         on the VAX, for DAYS up to 1.0, 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 DAYS may exceed 1.0.  In cases where it
         does not, it is up to the caller to test for and handle the
         case where DAYS is very nearly 1.0 and rounds up to 24 hours,
         by testing for IHMSF(1)=24 and setting IHMSF(1-4) to zero.

  Called:  slDDTF

  P.T.Wallace   Starlink   12 December 1993

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

.fi
.endhelp