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arXiv · 2509.23696

On Computing the Copositive Minimum and its Representatives

Alexander Oertel·Achill Schürmann
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Abstract

Computing the copositive minimum of a strictly copositive quadratic form is a natural generalization of computing the arithmetical minimum of a positive definite one. In this paper we show that this generalized problem is NP-complete. Moreover, we describe a practical method to calculate all shortest vectors using the LDLT-decomposition in a big class of special cases. Our numerical tests show that our method performs significantly better than previous approaches.

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Alexander Oertel, Achill Schürmann. 2025-09-28. On Computing the Copositive Minimum and its Representatives. https://arxiv.org/abs/2509.23696

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