Abstract
When considering approximation of continuous periodic functions f: R d → R by blending-type approximants which depend on directions ξ1,…,ξν ∈ R d directional moduli of smoothness (1) are appropriate measures of smoothness of /. In this paper, we introduce equivalent directional K- functionals. As an application, we obtain a result on the degree of approximation by certain trigonometric blending functions.
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Cottin, C. Directional K- Functionals Claudia Cottin. Results. Math. 24, 211–221 (1993). https://doi.org/10.1007/BF03322331
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DOI: https://doi.org/10.1007/BF03322331