Abstract
We consider theL p-convergence of interpolatory processes for nonsmooth functions. Therefore we use generalizations of the well-known Marcinkiewicz-Zygmund inequality for trigonometric polynomials to the case of algebraic polynomials, extending a result of Y. Xu. Particularly, we obtain the order of convergence for certain Lagrange and quasi-Lagrange interpolatory processes on generalized Jacobi nodes. Our approach enables us also to discuss the influence of additional nodes near the endpoints ±1.
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Prestin, J. Lagrange interpolation on extended generalized Jacobi nodes. Numer Algor 5, 179–190 (1993). https://doi.org/10.1007/BF02215680
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DOI: https://doi.org/10.1007/BF02215680