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NP-completeness of Partial Chirotope Extendibility

Patrick Baier
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Abstract

In the monograph "Axioms and Hulls" (1992) Donald Knuth studies some axiomatizations of geometric situations. The structures described by one of the axiom systems are called CC-systems. Knuth proves that it is NP-complete to decide, whether a partially defined CC-system can be extended to a complete CC-system. The aim of this note is to show that Knuth's proof of this result also implies that it is NP-complete to decide the extendability of partially defined chirotopes.

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Patrick Baier. 2005-04-21. NP-completeness of Partial Chirotope Extendibility. https://arxiv.org/abs/math/0504430

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