build_partition_mdds - build a partition of MDDs for the flattened network
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   build_partition_mdds [-h] [-i] [-n <list>] [-s <num>] [-t <seconds>] [-v]
   [<method>]

   Build the MDDs of a flattened network. Depending on the method selected, the
   MDDs for the combinational outputs (COs) are built in terms of either the
   combinational inputs (CIs) or in terms of some subset of intermediate nodes
   of the network. The MDDs built are stored in a DAG called a "partition". The
   vertices of a partition correspond to the CIs, COs, and any intermediate
   nodes used. Each vertex has a multi-valued function (represented by MDDs)
   expressing the function of the corresponding network node in terms of the
   partition vertices in its transitive fanin. Hence, the MDDs of the partition
   represent a partial collapsing of the network.

   This  command  must  be preceded by the commands flatten_hierarchy and
   static_order. The partition built is stored with the network for use by
   other commands, such as simulate, compute_reach, model_check, etc. This
   command  has  no  affect  when invoked on a network that already has a
   partition.  To  remove  the  existing partition of a network, reinvoke
   flatten_hierarchy.

   The choice of method determines which intermediate nodes are used. The inout
   method represents one extreme where no intermediate nodes are used, and
   total represents the other extreme where every node in the network has a
   corresponding vertex in the partition. If no method is specified on the
   command line, then the value of the flag partition_method is used (this flag
   is set by the command set partition_method), unless it does not have a
   value, in which case the forntier method is used. The different methods
   available are:

     inout Expresses the combinational outputs in terms of the combinational
          inputs.

     total The partition built is isomorphic to the combinational part of the
          network. The function of each node is expressed in terms of its
          immediate fanins. If the -i is used the function attached to each
          vertex is computed as a function of the combinational inputs.

     partial Builds a partition using the intermediate nodes specified with the
          -n option or the -f option.

     frontier  (default)  Builds  a  partition  creating vertices for the
          intermediate nodes as needed in order to control the BDD size. The
          threshold  value  for  the BDD size can be set by the parameter
          "partition_threshold". This method encompasses both "inout" (set
          partition_threshold  parameter  to  infinity)  and "total" (set
          partition_threshold parameter to 0).

     boundary Builds a partition in a fashion that preserves all nodes that are
          Input/Output  nodes of any hnode in the hierarchy rooted at the
          current hnode.

   Command options:

   -h
          Print the command usage.

   -i
          Build the multi-valued functions of each partition vertex in terms of
          the combinational inputs, rather than in terms of its transitive
          fanin vertices.

   -n <list>
          Used  in  conjunction  with the partial method. List is a comma
          separated list of network nodes to use as intermediate nodes in the
          partition.

   -s <num>
          Level  of  severity  of a post-computation check applied to the
          partition data structure (0 by default, meaning no check).

   -t <seconds>
          Time in seconds allowed to build the partition. If the computation
          time goes above that limit, the process of building the partition is
          aborted. The default is no limit.

   -v
          Turn on the verbosity.
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          Last updated on 20100410 00h02