DPvis - A Tool to Visualize the Structure of SAT Instances

We present DPVIS, a Java tool to visualize the structure of SAT instances and runs of the DPLL (Davis-Putnam-Logemann-Loveland) procedure. DPVIS uses advanced graph layout algorithms to display the problem’s internal structure arising from its variable dependency (interaction) graph. DPVIS is also able to generate animations showing the dynamic change of a problem’s structure during a typical DPLL run. Besides implementing a simple variant of the DPLL algorithm on its own, DPVIS also features an interface to MiniSAT, a state-of-the-art DPLL implementation. Using this interface, runs of MiniSAT can be visualized—including the generated search tree and the effects of clause learning. DPVIS is supposed to help in teaching the DPLL algorithm and in gaining new insights in the structure (and hardness) of SAT instances.