Sim Specs

This forum is for discussion of the System Dynamics model representation standard XMILE. Discussion here will be monitored by the Society's technical standards committee with ideas and concerns conveyed to the OASIS Technical Committee responsible for defining the standard.
Forum rules
Please note: By posting here you grant permission to the Society Technical Committee members to repost with attribution on the OASIS discussion forum. If you have material for which you wish to maintain copyright control please post a link to the copyrighted work.
Post Reply
Robert Eberlein
Site Admin
Posts: 179
Joined: Sat Dec 27, 2008 8:09 pm

Sim Specs

Post by Robert Eberlein » Mon Aug 05, 2013 6:19 pm

It is important that the run specifications be computable and not just specified constants. The draft specification does not make it clear whether this is possible. The most common use for this is a simulation dependent end time, but a variable dt is also usable and in some cases the starting time might be dependent on some initial computation.

In the case of nested models it would be nice if these models could also run standalone - therefore having a full set of sim specs would be helpful (though optional). This is true even if when used as a nested model no sim specs would be used. Therefore hints about which to use when would be helpful - see also the model nesting discussion.

The inclusion of a sampling frequency (aka PRTPER, PLTPER, SAVEPER) would also be helpful here.

Thomas Fiddaman
Posts: 152
Joined: Thu Jan 15, 2009 6:55 pm
Location: Bozeman, MT
Contact:

Re: Sim Specs

Post by Thomas Fiddaman » Tue Aug 13, 2013 2:44 pm

Good points.

For nested models, an independent <sim spec> would also enable the host model to pass start/end times etc. as parameters to the nested model, in cases were the nested model represents a subproblem solved on an independent time axis.

Karim Chichakly
Posts: 46
Joined: Fri Apr 10, 2009 11:52 am

Re: Sim Specs

Post by Karim Chichakly » Tue Aug 13, 2013 4:50 pm

That's an interesting point, Tom. XMILE currently allows macros to have variable sim specs (for precisely the purpose you describe), but not models, an asymmetry we should rectify.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest