Abstract
By “approximately singular system” we mean a system of multivariate polynomials the dimension of whose variety is increased by small amounts of perturbations. First, we give a necessary condition that the given system is approximately singular. Then, we classify polynomial systems which seems ill-conditioned to solve numerically into four types. Among these, the third one is approximately singular type. We give a simple well-conditioning method for the third type. We test the third type and its well-conditioned systems by various examples, from viewpoints of “global convergence”, “local convergence” and detail of individual computation. The results of experiments show that our well-conditioning method improves the global convergence largely.
Work supported by Japan Society for the Promotion of Science under Grants 23500003 and 08039686.
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Sasaki, T., Inaba, D. (2012). Approximately Singular Systems and Ill-Conditioned Polynomial Systems. In: Gerdt, V.P., Koepf, W., Mayr, E.W., Vorozhtsov, E.V. (eds) Computer Algebra in Scientific Computing. CASC 2012. Lecture Notes in Computer Science, vol 7442. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-32973-9_26
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DOI: https://doi.org/10.1007/978-3-642-32973-9_26
Publisher Name: Springer, Berlin, Heidelberg
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