Abstract
The problem of analytic approximation of a smooth closed curve specified by a set of its points on the complex plane is proposed. An algorithmic method for constructing an approximating lemniscate is proposed and investigated. This method is based on a mapping of the curve to be approximated onto the phase circle; the convergence of the method is proved. The location of the lemniscate foci inside the curve provides the degrees of freedom for the focal approximation.
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Original Russian Text © T.A. Rakcheeva, 2011, published in Zhurnal Vychislitel’noi Matematiki i Matematicheskoi Fiziki, 2011, Vol. 51, No. 11, pp. 1963–1972.
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Rakcheeva, T.A. Focal approximation on the complex plane. Comput. Math. and Math. Phys. 51, 1847–1855 (2011). https://doi.org/10.1134/S0965542511110145
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DOI: https://doi.org/10.1134/S0965542511110145