Abstract
In the spaces Sp of functions of several variables, 2π-periodic in each variable, we study the approximative properties of operators A Δϱ,r and P Δϱ,s , which generate two summation methods of multiple Fourier series on triangular regions. In particular, in the terms of approximation estimates of these operators, we give a constructive description of classes of functions, whose generalized derivatives belong to the classes SpHω.
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Savchuk, V.V., Shidlich, A.L. Approximation of functions of several variables by linear methods in the space Sp. ActaSci.Math. 80, 477–489 (2014). https://doi.org/10.14232/actasm-012-837-8
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DOI: https://doi.org/10.14232/actasm-012-837-8