[Repast-developer] getTickCount/getCurrentTime - why typed as doubles?

[Les G. <ga...@ui...>]

I'm implementing some extensions to Repast.
Regarding uchicago.src.sim.engine:

The TickCounter interface specifies the method "getTickCount" which
returns a double.  The SimModel class specifies the method
"getCurrentTime" which also returns a double.

Question:

  Both these methods refer to simulation ticks or times. Why
  are their return types specified as "double", which is a floating
  point type, and not int or long? When would a RePast-computed tick or
  time count ever be fractional, i.e., anything but an integer?

  (If I've got this right, the method of updating sim ticks is through
  reading "nextTime" fields in BasicAction.java; BasicActions are
  placed in a priority queue called ActionQueue (nb: Java 1.5 now has
  java.util.PriorityQueue). Sim time is advanced to the minimum time
  (next) entry in this queue - so it can leap forward by more than one
  tick depending on the times for which the BasicActions were
  (re)inserted in the ActionQueue. Nonetheless, all the time specifiers
  I could find in the RePast code are integer values, typically 0 or 1,
  and it's hard to envision when a float would be needed for a
  simtick.)

Suggestion:

  While the inheritance and implementation graphs for these interfaces
  are clearly different, both methods seem to be intending to return
  the current simulation tick or time. Why the difference in names
  then?  It seems like it might be a good idea to unify the concept of
  getting access to the current simulation time/tick, unless there
  really is some underlying conceptual difference that I'm not seeing.

Thanks,

- Les

(not a list subscriber, so please respond directly as well as to the 
list - thanks.)