Abstract
In this paper, we continue our research on characterizing the order of linear approximation schemes from shift-invariant spaces, which was started in [4]. Our extension of earlier results applies to various aspects: Firstly, in the definition of the operators we allow more general functions, viz. distributions of finite order. Secondly, we consider the non-stationary case, where the operators may depend on the scaling parameter. Thirdly, we bound the error for derivatives as well, i.e., we can bound the error of simultaneous approximation. Finally, we derive a characterization of the full norm approximation order in addition to the usual seminorm approximation order. Our results are applied to the following examples: Thin-plate splines, multiquadrics, and four-directional box splines.
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De Boor, C., De Vore, R. andRon, A.,Approximation from shift-invariant subspaces of L 2(ℝd), Trans. Amer. Math. Soc.,341 (1994), 787–806.
Jetter, K.,Multivariate approximation from the cardinal interpolation point of view, in Approximation Theory VII, E.W. Cheney, C.K. Chui and L.L. Schumaker, eds., Academic Press, New York, 1993, 131–161.
Jetter, K. andStöckler, J.,Algorithms for cardinal interpolation using box splines and radial basis functions, Numer. Math.,60 (1991), 97–114.
Jetter, K. andZhou, D.X.,Order of linear approximation from shift-invariant spaces, Constr. Approximation, to appear.
Jetter, K. andZhou, D.X.,Order of linear approximation from shift-invariant spaces II: Non-stationary and simultaneous approximation, Schriftenreihe des Fachbereich Mathematik SM-DU-269, Universität Duisburg, (September 1994).
Jia, R.Q. andLei, J.J.,Approximation by multiinteger translates of functions having global support, J. Approximation Theory,72 (1993), 2–23.
Ron, A.,The L 2 -approximation orders of principal shift-invariant spaces generated by a radial basis function, in Numerical Methods of Approximation Theory, D. Braess and L.L. Schumaker, eds., Birkhäuser-Verlag, Basel, 1992.
Zhao, K.,Simultaneous approximation from PSI spaces, J. Approximation Theory81 (1995), 166–184.
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Conferenza tenuta da K. Jetter il 5 ottobre 1995
The second author is supported by the Alexander-von-Humboldt Foundation. He is on leave from Academia Sinica.
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Jetter, K., Zhon, DX. Seminorm and full norm order of linear approximation from shift-invariant spaces. Seminario Mat. e. Fis. di Milano 65, 277–302 (1995). https://doi.org/10.1007/BF02925261
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DOI: https://doi.org/10.1007/BF02925261