Abstract
Local parabolic splines on the axis \(\mathbb R\) with equidistant nodes realizing the simplest local approximation scheme are considered. But, instead of the values of functions at the nodes, its formula approximates their mean values in symmetric neighborhoods of these nodes. For an arbitrary averaging step \(H\) more than twice as large as the grid step \(h\) of the spline, the approximation errors are calculated exactly in the uniform metric of these functions and their derivatives for the function class \(W_\infty^2\). For small averaging steps \(H\le 2h\), these quantities were calculated by E. V. Strelkova (Shevaldina) in 2007.
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This work is part of the research carried out at the Ural Mathematical Center.
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Shevaldin, V.T. Local Approximation by Parabolic Splines in the Mean for Large Averaging Intervals. Math Notes 108, 733–742 (2020). https://doi.org/10.1134/S0001434620110127
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DOI: https://doi.org/10.1134/S0001434620110127