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arXiv · 2409.03357

Constrained mock-Chebyshev least squares approximation for Hermite interpolation

Francesco Dell'Accio·Francisco Marcellán·Federico Nudo
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Abstract

This paper addresses the challenge of function approximation using Hermite interpolation on equally spaced nodes. In this setting, standard polynomial interpolation suffers from the Runge phenomenon. To mitigate this issue, we propose an extension of the constrained mock-Chebyshev least squares approximation technique to Hermite interpolation. This approach leverages both function and derivative evaluations, resulting in more accurate approximations. Numerical experiments are implemented in order to illustrate the effectiveness of the proposed method.

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Francesco Dell'Accio, Francisco Marcellán, Federico Nudo. 2024-09-05. Constrained mock-Chebyshev least squares approximation for Hermite interpolation. https://arxiv.org/abs/2409.03357

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