Results 11 to 20 of about 54,203 (295)
Weighted rational approximation in the complex plane
Journal Des Mathematiques Pures Et Appliquees, 1999 Given a domain \(G\subset\mathbb{C}\), \(f\) analytic in \(G\), a weight function \(W\) also analytic in \(G\) and \(W(z)\neq 0\) in \(G\), and \(\gamma\) with \(0\leq\gamma\leq 1\), the authors study the rational approximation property of \(W\): There exist rational functions \(R_i=P_{m_i}/Q_{n_i}\) where \(P,Q\) are polynomials of degree \(\leq m_i\)
Pritsker, I.E., Varga, R.S.
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Best approximation over the whole complex plane
Journal of Approximation Theory, 1982 AbstractBest rational approximation over the whole complex plane is investigated. While existence is elementary, there is not always uniqueness—every constant may be the best constant approximation to f(z) = z. However, under certain circumstances, the set of best approximations is, in a sense, bounded.
D S Lubinsky
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Approximation of Functions by Rational Functions on Closed Curves of the Complex Plane
Arabian Journal for Science and Engineering, 2011 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Sadulla Z Jafarov
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Polynomial approximation of analytic functions on a finite number of continua in the complex plane
Journal of Approximation Theory, 2005 The author generalizes a theorem of Dzyadyk on polynomial approximation on a continuum in the complex plane to the case of compact sets that consist of finitely many continua.
Vladimir Andrievskii
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Weighted uniform polynomial approximation and moduli of smoothness on continua in the complex plane
Journal of Approximation Theory, 2012 The starting point of the analysis is a result due to \textit{G. Mastroianni} and \textit{V. Totik} [J. Approx. Theory 110, No. 2, 180--199 (2001; Zbl 0981.41016)]. The aim of the paper is to extend this result to the case of weighted polynomial approximation on compact sets in the complex plane. The main results of the paper are contained in Theorem 1
Vladimir Andrievskii
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Weighted polynomial approximation in the complex plane [PDF]
Electronic Research Announcements of the American Mathematical Society, 1997 Given a pair ( G , W ) (G,W) of an open bounded set G G in the complex plane and a weight function W ( z ) W(z) which is analytic and different from zero in G G , we consider the problem of the locally uniform ...
Pritsker, Igor E., Varga, Richard S.
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The Complexity of Approximating the Matching Polynomial in the Complex Plane [PDF]
ACM Transactions on Computation Theory, 2021 We study the problem of approximating the value of the matching polynomial on graphs with edge parameter γ, where γ takes arbitrary values in the complex plane. When γ is a positive real, Jerrum and Sinclair showed that the problem admits an FPRAS on general graphs.
Ivona Bezáková +3 more
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Sparse Plane Wave Approximation of Acoustic Modes to Address Basis Mismatch
Applied Sciences, 2022 Low-frequency sound field reconstruction in an enclosed space has many applications where the plane wave approximation of acoustic modes plays a crucial role.
Jian Xu +3 more
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Zeros and approximations of Holant polynomials on the complex plane
computational complexity, 2022 AbstractWe present fully polynomial time approximation schemes for a broad class of Holant problems with complex edge weights, which we call Holant polynomials. We transform these problems into partition functions of abstract combinatorial structures known as polymers in statistical physics.
Casel, Katrin (Dr.) +4 more
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A Class of Quadrature Rules for Complex Cauchy Principal Value Integrals [PDF]
International Journal of Mathematical, Engineering and Management Sciences, 2023 This article is fully devoted to the numerical approximation of Cauchy-type integrals in the complex plane. A class of degree eight quadrature rules is formulated from a family of Gauss-type two-point rules based on the method of extrapolation. The basic
Arup Kumar Saha +2 more
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