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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