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arXiv · 1602.03993

Implicitization of Hypersurfaces

John Abbott·Anna Maria Bigatti·Lorenzo Robbiano
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Abstract

We present new, practical algorithms for the hypersurface implicitization problem: namely, given a parametric description (in terms of polynomials or rational functions) of the hypersurface, find its implicit equation. Two of them are for polynomial parametrizations: one algorithm, "ElimTH", has as main step the computation of an elimination ideal via a \textit{truncated, homogeneous} Gr\"obner basis. The other algorithm, "Direct", computes the implicitization directly using an approach inspired by the generalized Buchberger-M\"oller algorithm. Either may be used inside the third algorithm, "RatPar", to deal with parametrizations by rational functions. Finally we show how these algorithms can be used in a modular approach, algorithm "ModImplicit", for avoiding the high costs of arithmetic with rational numbers. We exhibit experimental timings to show the practical efficiency of our new algorithms.

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John Abbott, Anna Maria Bigatti, Lorenzo Robbiano. 2016-02-12. Implicitization of Hypersurfaces. https://arxiv.org/abs/1602.03993

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