Results 21 to 30 of about 822,442 (292)

Deterministic and random approximation by the combination of algebraic polynomials and trigonometric polynomials

Open Mathematics, 2021
Fourier approximation plays a key role in qualitative theory of deterministic and random differential equations. In this paper, we will develop a new approximation tool.
Zhang Zhihua
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Approximation by homogeneous polynomials [PDF]

Journal of Approximation Theory, 2013
Uniform approximations by even degree homogeneous polynomials are considered. For a centrally symmetric convex set with nonempty interior, all even continuous functions on its boundary (in two space dimensions; the problem is open for higher dimensions) can be uniformly approximated by them. This is a new, more elementary proof of this fact.
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Numerical integration by the matrix method of boundary value problems for linear inhomogeneous ordinary differential equations of the third order with variable coefficients

Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2018
The use of the Taylor polynomial of the second degree when approximating the derivatives by finite differences leads to the second order of approximation of the traditional method of nets in the numerical integration of second-order ordinary differential
Vladimir N Maklakov, Yanina G Stelmakh
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On the Approximation of the Jacobi Polynomials

Rocky Mountain Journal of Mathematics, 2007
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Elias, Uri, Gingold, Harry
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The evaluation of the order of approximation of the matrix method for numerical integration of the boundary value problems for systems of linear non-homogeneous ordinary differential equations of the second order with variable coefficients. Message 1. Boundary value problems with boundary conditions of the first kind

Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2016
We present the first message of the cycle from two articles where the rearrangement of the order of approximation of the matrix method of numerical integration depending on the degree in the Taylor’s polynomial expansion of solutions of boundary value ...
Vladimir N Maklakov
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Convexity, Markov Operators, Approximation, and Related Optimization

Mathematics, 2022
The present review paper provides recent results on convexity and its applications to the constrained extension of linear operators, motivated by the existence of subgradients of continuous convex operators, the Markov moment problem and related Markov ...
Octav Olteanu
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Polynomial-Like Approximation [PDF]

Mathematical Tables and Other Aids to Computation, 1954
Abstract : This is a short note on approximate representation for computing purposes of continuous real-valued functions of several real variables by finite sums of functions separable in the individual variables.
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Optimal Approximation of Biquartic Polynomials by Bicubic Splines

EPJ Web of Conferences, 2018
Recently an unexpected approximation property between polynomials of degree three and four was revealed within the framework of two-part approximation models in 2-norm, Chebyshev norm and Holladay seminorm.
Kačala Viliam, Török Csaba
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The evaluation of the order of approximation of the matrix method for numerical integration of the boundary value problems for systems of linear non-homogeneous ordinary differential equations of the second order with variable coefficients. Message 2. Boundary value problems with boundary conditions of the second and third kind

Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2017
We present the second message of the cycle from two articles where the rearrangement of the order of approximation of the matrix method of numerical integration depending on the degree in the Taylor’s polynomial expansion of solutions of boundary value ...
Vladimir N Maklakov
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Numerical integration by the matrix method and evaluation of the approximation order of difference boundary value problems for non-homogeneous linear ordinary differential equations of the fourth order with variable coefficients

Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2020
The use of the second degree Taylor polynomial in approximation of derivatives by finite difference method leads to the second order approximation of the traditional grid method for numerical integration of boundary value problems for non-homogeneous ...
Vladimir Nikolaevich Maklakov, Mariya Aleksandrovna Ilicheva   +1 more
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