Results 101 to 110 of about 2,105 (196)
Random sampling of sparse trigonometric polynomials
, 2006 We study the problem of reconstructing a multivariate trigonometric polynomial having only few non-zero coefficients from few random samples. Inspired by recent work of Candes, Romberg and Tao we propose to recover the polynomial by Basis Pursuit, i.e ...
Holger Rauhut, Rauhut, Holger
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Efficient Spectral Estimation by MUSIC and ESPRIT with Application to Sparse FFT [PDF]
, 2020 In spectral estimation, one has to determine all parameters of an exponential sum for finitely many (noisy) sampled data of this exponential sum. Frequently used methods for spectral estimation are MUSIC (MUltiple SIgnal Classification) and ESPRIT ...
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Alternating trigonometric polynomials
Journal of Approximation Theory, 1987 Set \(t_ k=h_ n+\{k\pi /(n+1)\}\), \(k=0,1,...,2n+1\), \(0\leq h_ ...
openaire +2 more sources
Combinatorial identities related to Eigen-function decompositions of Hill operators: open questions
, 2013 We formulate three open questions related to enumerative combinatorics, which arise in the spectral analysis of Hill operators with trigonometric polynomial ...
Djakov, Plamen Borissov +1 more
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The Crest factor for trigonometric polynomials. Part I: Approximation theoretical estimates
Journal of Numerical Analysis and Approximation Theory, 2001 The Chebyshev norm of a degree n trigonometric polynomial is estimated against a discrete maximum norm based on equidistant sampling points where, typically, oversampling rather than critical sampling is used. The bounds are derived from various methods
K. Jetter, G. Pfander, G. Zimmermann
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Equivalence between various Shape Preserving Approximations of periodic functions
Researches in MathematicsWe show that the validity of Jackson-type estimates in comonotone and coconvex approximations of continuous $2\pi$-periodic functions by trigonometric polynomials is equivalent to the validity of the corresponding estimates of approximation by continuous
D. Leviatan, O.V. Motorna, I.O. Shevchuk
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STATISTICAL SYNTHESIS OF FORECAST CHARACTERISTICS OF COMPLEX TECHNICAL SYSTEM BY TIME SERIES
Научный вестник МГТУ ГА, 2016 The article analyses the problem of building a medium-term forecast of the recovery trend in the average. We present a method of recovery trend in the form of a polynomial whose coefficients are determined by the inverse functions which are approximated ...
N. A. Severcev +2 more
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On estimates of M-term approximations of the Sobolev class in the Lorentz space
Қарағанды университетінің хабаршысы. Математика сериясыIn the paper spaces of periodic functions of several variables were considered, namely the Lorentz space L2,τ(Tm), the class of functions with bounded mixed fractional derivative Wr2,τ, 1 ≤ τ < ∞, and the order of the best M-term approximation of a ...
Г. Акишев +1 more
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Trigonometric polynomial basis functions.
(a) n = 4, l1 = l2 = −1, 0, 1, 2, (b) n = 6, l1 = l2 = −1, 0, 1, 2.
Shazia Javed (17720835) +3 more
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Fluctuations of the Number of Critical Points of Random Trigonometric Polynomials
, 2013 Denote by Znthe number of critical points of a random trigonometric polynomial of degree ≤ n We prove that as ν→∞ the expectation of Zν is asymptotic to 2ν √⅗ while its variance is asymptotic to δ∞νwhere δ∞≈ 0.35.
Liviu I. Nicolaescu
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