Class Mdd_mcd
Solve a structured CTMC whose EXACT reachable state space is stored in a decision diagram, by building and iterating K level-CTMCs (a decision-diagram-guided aggregation), after A.S. Miner, G. Ciardo, S. Donatelli, "Using the exact state space of a Markov model to compute approximate stationary measures", SIGMETRICS 2000.
The method never forms the |S|-state generator or probability vector. It keeps one CTMC per decision-diagram level k, over states M_k = {(p,i_k)} with p a level-k node and i_k a local state on a non-null arc, and iterates the coupled system to a fixed point. The single approximation (Eq. 5) is Pr{i_k | alpha} = Pr{i_k | p}: the local-state law at level k depends only on the node p, not the full path above it, which the exact reachability the diagram encodes justifies. For product-form models the method is EXACT (paper Sec. 5), so on a single-class closed QN it reproduces SolverCTMC.
Orientation. The paper indexes levels K (top/root) down to 1
(bottom/terminal); MDD uses level 0 as the root. This class works in
the paper's orientation with 0-based indices, so paper level k (0 = bottom)
maps to MDD level K-1-k and to station K-1-k. Getting this backwards silently
mislabels every per-station metric.
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Method Summary
Modifier and TypeMethodDescriptionstatic MddMcdResultmdd_mcd(MddStruct mdds, MddDescriptor desc) Run the aggregation with the default level-iteration knobs.static MddMcdResultmdd_mcd(MddStruct mdds, MddDescriptor desc, MddMcdOptions options) Approximate stationary measures by decision-diagram-guided aggregation.
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Method Details
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mdd_mcd
Run the aggregation with the default level-iteration knobs. -
mdd_mcd
Approximate stationary measures by decision-diagram-guided aggregation.- Parameters:
mdds- the reachable set, in MDD orientationdesc- the Kronecker rate descriptoroptions- level-iteration knobs
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