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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