Best approximations of the classes B p,θ r of periodic functions of many variables in uniform metric

被引：0
作者：
Romanyuk A.S. [1 ]
机构：
[1] Institute of Mathematics, Ukrainian Academy of Sciences, Kiev
来源：
Ukrainian Mathematical Journal | 2006年 / 58卷 / 10期
关键词：
Periodic Function; Linear Method; Trigonometric Polynomial; Estimate Exact; Kolmogorov Width;
D O I：
10.1007/s11253-006-0155-9
中图分类号：
学科分类号：
摘要：
We obtain estimates exact in order for the best approximations of the classes B ∞,θ r of periodic functions of two variables in the metric of L ∞ by trigonometric polynomials whose spectrum belongs to a hyperbolic cross. We also investigate the best approximations of the classes B p,θ r , 1 p < ∞, of periodic functions of many variables in the metric of L ∞ by trigonometric polynomials whose spectrum belongs to a graded hyperbolic cross. © Springer Science+Business Media, Inc. 2006.
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页码：1582 / 1596
页数：14
相关论文
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