How to Use
Select digraph:
- dagw: DAG-width
- Directed: DAG decomp
- Acyclic: dagw=1?
DAG Decomposition
Like tree decomposition but the skeleton is a DAG, not a tree. Bags of vertices. Width = max bag size - 1. Captures directed reachability structure. More expressive than directed treewidth for some applications.
Applications
Parity games: central to verification (model checking μ-calculus). Bounded dagw → polynomial parity games. Also: directed network analysis, circuit complexity, information flow in directed networks.
Step-by-Step Instructions
- 1Select digraph.
- 2Build DAG decomp.
- 3Measure bag width.
- 4Check acyclicity.
- 5Apply parity games.