dynamic_var_ordering - Deals with the dynamic variable ordering.


dynamic_var_ordering [-d] [-e <method>] [-f <method>] [-h]

Controls the application and the modalities of (dynamic) variable ordering. Dynamic ordering is a technique to reorder the BDD variables to reduce the size of the existing BDDs. When no options are specified, the current status of dynamic ordering is displayed. At most one of the options -e, -f, and -d should be specified.

Dynamic ordering may be time consuming, but can often reduce the size of the BDDs dramatically. A good point to invoke dynamic ordering explicitly (using the -f option) is after the commands build_model, once the transition relation has been built. It is possible to save the ordering found using write_order in order to reuse it (using build_model -i order-file) in the future.

Command options:

-d
Disable dynamic ordering from triggering automatically.
-e <method>
Enable dynamic ordering to trigger automatically whenever a certain threshold on the overall BDD size is reached. <method> must be one of the following:
-f <method>
Force dynamic ordering to be invoked immediately. The values for <method> are the same as in option -e.

Last updated on 2011/04/06 21h:13