eclingo: A solver for Epistemic Logic Programs
This work addresses the need for efficient solvers in the domain of epistemic logic programming, offering incremental improvements over existing methods.
The authors tackled the problem of solving epistemic logic programs under Gelfond 1991 semantics by developing eclingo, a solver built on clingo that uses a guess-and-check strategy with optimizations to reduce search space. They showed that eclingo generally outperforms two state-of-the-art solvers on benchmark scenarios, though specific efficiency numbers are not provided.
We describe eclingo, a solver for epistemic logic programs under Gelfond 1991 semantics built upon the Answer Set Programming system clingo. The input language of eclingo uses the syntax extension capabilities of clingo to define subjective literals that, as usual in epistemic logic programs, allow for checking the truth of a regular literal in all or in some of the answer sets of a program. The eclingo solving process follows a guess and check strategy. It first generates potential truth values for subjective literals and, in a second step, it checks the obtained result with respect to the cautious and brave consequences of the program. This process is implemented using the multi-shot functionalities of clingo. We have also implemented some optimisations, aiming at reducing the search space and, therefore, increasing eclingo's efficiency in some scenarios. Finally, we compare the efficiency of eclingo with two state-of-the-art solvers for epistemic logic programs on a pair of benchmark scenarios and show that eclingo generally outperforms their obtained results. Under consideration for acceptance in TPLP.