Efficient Solving of Quantified Inequality Constraints over the Real Numbers

Stefan Ratschan

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Efficient Solving of Quantified Inequality Constraints over the Real Numbers

Stefan Ratschan

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Abstract

Let a quantified inequality constraint over the reals be a formula in the first-order predicate language over the structure of the real numbers, where the allowed predicate symbols are $\leq$ and $<$. Solving such constraints is an undecidable problem when allowing function symbols such $\sin$ or $\cos$. In the paper we give an algorithm that terminates with a solution for all, except for very special, pathological inputs. We ensure the practical efficiency of this algorithm by employing constraint programming techniques.

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Stefan Ratschan. 2002-11-14. Efficient Solving of Quantified Inequality Constraints over the Real Numbers. https://arxiv.org/abs/cs/0211016

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