Shared variables among multiple instances of FSMs

[Lutz, Charles D]

Hi Ptolemy hackers,   Here’s the first post, likely of many to come. We are new Ptolemy users here, although personally I’ve followed the project for several years (but never got around to diving in!).   We’re trying to figure out a way to use Ptolemy as a general purpose M&S tool, and a modeling strategy for things like usage of resources. A scenario could be something like the self-checkout systems at supermarkets – typically there are 4 or so stations available. When all are in use, customers wait in line until one becomes available.   We might model each customer’s behavior with a state machine, but then we need a “global variable” for the number of available stations, which would be incremented and decremented by the (concurrent) instances of customers. A (waiting) customer can then transition to e.g. a “checkout” state when this variable > 0 and decrement it on the way.   I’ve always had the impression that Ptolemy has a lot of depth, and now, getting into the details for real, that is an understatement! We are trying to get up to speed on how things work, so as we don’t know the theory yet, there could be problems with this approach, but we want to try something out, even if it just helps us understand the dynamics.   We have a simple model with which we’re trying to get a grasp on some basics.   At the top of the model, we have a MultipleInstanceComposite with a “MIC_out” port to a Display. Also, there is a “stationsAvailable” parameter, assigned value 4.   Inside the MIC is a ContinuousClock connected to the “trigger” port of a ModalModel; the MM has output ports “stations” and “bagging”, going to MIC_out.   Currently the only output actions are to write some test strings to the MM’s output ports.   Issues we’re having: Can’t seem to figure out how to get the concurrent FSMs to be able to see the top level parameter (again, could be a bad idea, just trying it for now…) Using DEDirector, I got a complaint that something with a HSDirector can only be used in a CTDomain; don’t know what HSDirector is, but I switched to CT No output on Display…   We are continuing in the manuals, but wanted perhaps to get a bit of a reality check…   Thanks in advance for any input / tips / warnings / etc…   Chuck Lutz Lockheed Martin Systems of Systems - Modeling and Operations Analysis BMC4I Modeling and Simulation Moorestown, NJ (856)638-7234 (office) [EMAIL PROTECTED]   “Everyone spoke of an information overload, but what there was in fact was a non-information overload.” – Richard Saul Wurman