论文信息 - Approximability of the classes B_{p,\theta}^r of periodic functions of several variables by linear methods and best approximations

Approximability of the classes B_{p,\theta}^r of periodic functions of several variables by linear methods and best approximations

Several questions of the approximability by linear methods of the Besov classes and of periodic functions of several variables, , are considered alongside their best approximations in the spaces and , respectively. Taken for approximation aggregates are trigonometric polynomials with spectrum in the step hyperbolic cross. Sharp (in order) estimates of the deviations of step hyperbolic Fourier sums on the classes , , in the space are also obtained.

A. Romanyuk | A S Romanyuk

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