Results 21 to 30 of about 72 (70)
Localization and summability of multiple Hermite series
International Journal of Mathematics and Mathematical Sciences, Volume 20, Issue 1, Page 61-74, 1997., 1995 The multiple Hermite series in Rn are investigated by the Riesz summability method of order α > (n − 1)/2. More precisely, localization theorems for some classes of functions are proved and sharp sufficient conditions are given. Thus the classical Szegö results are extended to the n‐dimensional case.
G. E. Karadzhov, E. E. El-Adad
wiley +1 more source
Fast and stable algorithms for discrete spherical Fourier transform [PDF]
, 1998 . In this paper, we propose an algorithm for the stable and efficient computation of Fourier expansions of square integrable functions on the unit sphere S ae R 3 , as well as for the evaluation of these Fourier expansions at special knots.
Tasche, Manfred +5 more
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Approximation by double Walsh polynomials
International Journal of Mathematics and Mathematical Sciences, Volume 15, Issue 2, Page 209-220, 1992., 1992 We study the rate of approximation by rectangular partial sums, Cesàro means, and de la Vallée Poussin means of double Walsh‐Fourier series of a function in a homogeneous Banach space X. In particular, X may be Lp(I2), where 1≦p < ∞ and I2 = [0, 1) × [0, 1), or CW(I2), the latter being the collection of uniformly W‐continuous functions on I2. We extend
Ferenc Móricz
wiley +1 more source
Concepts of generalized bounded variation and the theory of Fourier series
International Journal of Mathematics and Mathematical Sciences, Volume 9, Issue 2, Page 223-244, 1986., 1986 The aim of this article is to unify a large part of present knowledge about the behaviour of Fourier series of functions of generalized bounded variation. The connections between various concepts are discussed, particular attention being payed to those due to Waterman and Chanturiya.
M. Avdispahić
wiley +1 more source
Recent developments in the theory of Walsh series
International Journal of Mathematics and Mathematical Sciences, Volume 5, Issue 4, Page 625-673, 1982., 1982 We survey research done on the theory of Walsh series during the decade 1971‐1981. Particular attention is given to convergence of Walsh‐Fourier series, gap Walsh series, growth of Walsh‐Fourier coefficients, dyadic differentiation, and uniqueness of Walsh series.
William R. Wade
wiley +1 more source
Uniform Approximation and Explicit Estimates for the Prolate Spheroidal Wave Functions
, 2015 International audienceFor xed c, Prolate Spheroidal Wave Functions (PSWFs), denoted by ψ n,c , form an orthogonal basis with remarkable properties for the space of band-limited functions with bandwith c.
Karoui, Abderrazek, Bonami, Aline
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A Rational Moment Problem on the Unit Circle [PDF]
, 1997 Let fff k g 1 k=1 be a sequence of not necessarily distinct points on the complex unit circle. We consider the moment problem where it is to find a positive measure on [\Gammaß; ß] such that for ! 0 = 1 and !
Hendriksen, E. +11 more
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Kernels and best approximations related to the system of ultraspherical polynomials [PDF]
, 2005 22 pages, no figures.-- MSC2000 codes: 41A10; 41A17; 41A25; 42C10; 33C45.MR#: MR2129477 (2005k:41087)Zbl#: Zbl 1074.41003We study the uniformly bounded orthonormal system $ \Cal U_\lambda $ of functions $$ u_n (\lambda )}(x)=\varphi _n (\lambda )}(\cos x)
Marcellán, Francisco +5 more
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An orthonormal system on the construction of the generalized cantor set
, 1992 International Journal of Mathematics and Mathematical Sciences, Volume 16, Issue 4, Page 737-748, 1993.
Raafat Riad Rizkalla
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Multiplicative Systems on Ultra-Metric Spaces [PDF]
, 2010 AMS Subj. Classification: MSC2010: 42C10, 43A50, 43A75We perform analysis of certain aspects of approximation in multiplicative systems that appear as duals of ultrametric structures, e.g.
Memic, Nacima
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