Speed-Up Techniques for Negation in Grounding
Grounding is the task of reducing a first order formula to ground formula that is equivalent on a given universe, and is important in many kinds of problem solving and reasoning systems. One method for grounding is based on an extension of the relational algebra, exploiting the fact that grounding over a given domain is similar to query answering. In this paper, we introduce two methods for speeding up algebraic grounding by reducing the size of tables produced. One method employs rewriting of the formula before grounding, and the other uses a further extension of the algebra that makes negation efficient. We have implemented the methods, and present experimental evidence of their effectiveness.
KeywordsFree Variable Hamiltonian Cycle Relational Algebra Query Answering Negation Cost
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- 1.The Asparagus Library of Examples for ASP Programs, http://asparagus.cs.uni-potsdam.de/
- 4.Fagin, R.: Generalized first-order spectra and polynomial-time recognizable sets. In: SIAM-AMC Proceedings of Complexity of Computation, vol. 7, pp. 43–73 (1974)Google Scholar
- 8.Mohebali, R.: A method for solving np search based on model expansion and grounding. Master’s thesis, Simon Fraser University (2006)Google Scholar
- 9.Patterson, M., Liu, Y., Ternovska, E., Gupta, A.: Grounding for model expansion in k-guarded formulas with inductive definitions. In: Proc. IJCAI 2007, pp. 161–166 (2007)Google Scholar
- 10.Wittocx, J., Mariën, M., Denecker, M.: Grounding with bounds. In: Proc. AAAI 2008, pp. 572–577 (2008)Google Scholar