Results 1 to 10 of about 39,951 (138)
New Characterization for Nonlinear Weighted Best Simultaneous Approximation [PDF]
International Journal of Mathematics and Mathematical Sciences, 2009 This paper is concerned with the problem of a wide class of weighted best simultaneous approximation in normed linear spaces, and it establishes a new characterization result for the class of approximation by virtue of the notion of simultaneous regular ...
Xianfa Luo, Delin Wu, Jinsu He
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A Characterization of the Extended Best φ-Approximation Operator
Numerical Functional Analysis and Optimization, 2011 Given an non necessarily linear operator T defined from an Orlicz space L φ′(Ω, 𝒜, μ) into itself, where φ′ denote the derivative of a strictly convex function φ, we give necessary and sufficient conditions on T assuring that this operator is an extended best φ-approximation operator given a suitable σ-lattice ℒ ⊆ 𝒜.
Sérgio Favier, Felipe Zo
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Characterization of a best and a unique best approximation from constrained rationals
Computers and Mathematics With Applications, 1995 The necessary and sufficient conditions for the existence and the uniqueness of a best rational approximation with real positive denominator to the continuous functions are given. The theorems are established in the general framework of the space of functions defined on compact Hausdorff space.
G A Watson
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AxiomsSince the monotonicity of the best approximant is crucial to establish partial ordering methods, in this paper, we, respectively, characterize the best approximants in Banach function spaces and Lorentz spaces Γp,w, in which we especially focus on the ...
Dezhou Kong, Zhihao Xu, Yun Wang, Li Sun
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On Characterization of Best Approximation with Certain Constraints
Journal of Approximation Theory, 1998 Let \( \Phi_n := \text{span}\{\varphi_1,\dots,\varphi_n\}, \) be an \(n\)-dimensional subspace of real functions on \( [a,b] \) and assume that, for an integer \( k\geq 0, \) the \(k\)th derivatives \( \varphi_1^{(k)},\dots,\varphi_n^{(k)} \) are continuous.
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A VARIATIONAL CHARACTERIZATION OF THE BEST APPROXIMATION ELEMENT
Demonstratio Mathematica, 1999 Let \(X\) be a real normed space, \(G\) is a proper closed linear subspace of \(X\), and \(x_0\in X\setminus G\). The author shows that an element \(g_0\in G\) is a best approximation element of \(x_0\) in \(G\) if and only if for every \(f\in G^*_{x_0}\) with Ker \((f)=G\) the quadratic functional \(F_f:G_{x_0}\to {\mathbb{R}}, F_f(x)=\|x\|^2-2f(x ...
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Characterization of Best Approximation Points with Lattice Homomorphisms
Journal of Mathematical Extension, 2014 In this paper we prove some characterization theorems in the theory of best approximation in Banach lattices. We use a new idea for finding the best approximation points in an ideal.
H. R. Khademzadeh, H. Mazaheri
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A Characterization of Best Φ-Approximants [PDF]
Transactions of the American Mathematical Society, 1981 Let T T be an operator from an Orlicz space
Landers, D., Rogge, L.
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Fuzzy Best Simultaneous Approximation of a Finite Numbers of Functions [PDF]
Sahand Communications in Mathematical Analysis, 2019 Fuzzy best simultaneous approximation of a finite number of functions is considered. For this purpose, a fuzzy norm on $Cleft (X, Y right )$ and its fuzzy dual space and also the set of subgradients of a fuzzy norm are introduced.
Hossain Alizadeh Nazarkandi
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Approximation by trigonometric polynomials in the variable exponent weighted Morrey spaces
Karpatsʹkì Matematičnì Publìkacìï, 2021 In this paper we investigate the best approximation by trigonometric polynomials in the variable exponent weighted Morrey spaces ${\mathcal{M}}_{p(\cdot),\lambda(\cdot)}(I_{0},w)$, where $w$ is a weight function in the Muckenhoupt $A_{p(\cdot)}(I_{0 ...
Z. Cakir +3 more
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