Re: Finite state machine in python
For simplistic FSMs, if you want to avoid hand-coding all the transitions, actions etc., you could consider something like Libero ( http://www.cs.vu.nl/~eliens/documents/libero/lrintr.htm), although the last I checked Libero didn't generate Python yet (but I believe there might be similar options available with Python, though haven't come accross anything). Machine generated FSMs can be suboptimal for many cases though. On Sun, Sep 13, 2009 at 10:28 AM, CTO debat...@gmail.com wrote: On Sep 12, 4:39 pm, Peng Yu pengyu...@gmail.com wrote: Hi, I have see some discussion on the implementation of finite state machine in python. Can somebody point to me the best way in implenting an FSM in python? http://code.activestate.com/recipes/146262/ Regards, Peng I wrote an example of how to do it using Graphine a while back. Probably not the most efficient in the world, but pretty easy to read, and it allows you to add and remove states and transitions easily. URL: http://gitorious.org/graphine/pages/GraphineForPythonistas Geremy Condra -- http://mail.python.org/mailman/listinfo/python-list -- regards, Banibrata http://www.linkedin.com/in/bdutta -- http://mail.python.org/mailman/listinfo/python-list
Re: Finite state machine in python
On Saturday 12 September 2009 22:39:10 Peng Yu wrote: Hi, I have see some discussion on the implementation of finite state machine in python. Can somebody point to me the best way in implenting an FSM in python? http://code.activestate.com/recipes/146262/ You can go a long way with a far simpler model than the one in that recipe: 1) Define a routine for every state. 2) Have every state do the following: (i) Run the code to make the side effects like outputs happen. (ii) Scan the conditions for the state transitions relevant to this state. (Only the arrows leaving this state on the state diagram.) (iii) Return the next state (either the same or a different state). 3) The main loop of a long running machine then looks like this: next_state = start_state() while True: next_state = next_state() time.sleep(step_time) # if needed This simple model is surprisingly powerful, and it can be expanded to run a bundle of such machines in parallel very easily, by keeping a list of next_states and continuously cycling through and updating the list. You do not even need a dispatch dictionary. This is about the simplest model for making FSMs that I know of. Not sure if it is the best - best for what?. - Hendrik -- http://mail.python.org/mailman/listinfo/python-list
Finite state machine in python
Hi, I have see some discussion on the implementation of finite state machine in python. Can somebody point to me the best way in implenting an FSM in python? http://code.activestate.com/recipes/146262/ Regards, Peng -- http://mail.python.org/mailman/listinfo/python-list
Re: Finite state machine in python
I have see some discussion on the implementation of finite state machine in python. Can somebody point to me the best way in implenting an FSM in python? To offer a best way requires knowing more about what you're trying to accomplish. Are you looking for just some fixed states? are you looking to dynamically adjust the available states? Is this workflow for a single user, or is it for multiple users? A FSM merely involves a list of states and the transitions between them. You can augment the states and/or the transitions with additional metadata. You can store your states in fixed internal hard-coded structures, or you can store them in a file/database that can grow external. I posted information on doing this with a SQL-ish database (whether sqlite or whatever) a while back, so you can see a more complex version of tracking this info: http://article.gmane.org/gmane.comp.python.general/624448 Hope this gives you some ideas from which to choose an option that's best for your needs. -tkc -- http://mail.python.org/mailman/listinfo/python-list
Re: Finite state machine in python
On Sep 12, 4:39 pm, Peng Yu pengyu...@gmail.com wrote: Hi, I have see some discussion on the implementation of finite state machine in python. Can somebody point to me the best way in implenting an FSM in python? http://code.activestate.com/recipes/146262/ Regards, Peng I wrote an example of how to do it using Graphine a while back. Probably not the most efficient in the world, but pretty easy to read, and it allows you to add and remove states and transitions easily. URL: http://gitorious.org/graphine/pages/GraphineForPythonistas Geremy Condra -- http://mail.python.org/mailman/listinfo/python-list
