The Community Structure of SAT Formulas

  • Carlos Ansótegui
  • Jesús Giráldez-Cru
  • Jordi Levy
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7317)


The research community on complex networks has developed techniques of analysis and algorithms that can be used by the SAT community to improve our knowledge about the structure of industrial SAT instances. It is often argued that modern SAT solvers are able to exploit this hidden structure, without a precise definition of this notion.

In this paper, we show that most industrial SAT instances have a high modularity that is not present in random instances. We also show that successful techniques, like learning, (indirectly) take into account this community structure. Our experimental study reveal that most learnt clauses are local on one of those modules or communities.


Community Structure Bipartite Graph Community Detection Original Formula Distinct Community 
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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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Carlos Ansótegui
    • 1
  • Jesús Giráldez-Cru
    • 2
  • Jordi Levy
    • 2
  1. 1.DIEIUniv. de LleidaSpain
  2. 2.IIIA-CSICSpain

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