DRAT-trim: Efficient Checking and Trimming Using Expressive Clausal Proofs

  • Nathan Wetzler
  • Marijn J. H. Heule
  • Warren A. HuntJr.
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8561)


The DRAT-trim tool is a satisfiability proof checker based on the new DRAT proof format. Unlike its predecessor, DRUP-trim, all presently known SAT solving and preprocessing techniques can be validated using DRAT-trim. Checking time of a proof is comparable to the running time of the proof-producing solver. Memory usage is also similar to solving memory consumption, which overcomes a major hurdle of resolution-based proof checkers. The DRAT-trim tool can emit trimmed formulas, optimized proofs, and new TraceCheck +  dependency graphs. We describe the output that is produced, what optimizations have been made to check RAT clauses, and potential applications of the tool.


Dependency Graph Proof Checker Input Formula Extended Resolution Drat Format 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Nathan Wetzler
    • 1
  • Marijn J. H. Heule
    • 1
  • Warren A. HuntJr.
    • 1
  1. 1.The University of Texas at AustinUSA

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