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arXiv · 2106.05714

A shape preserving quasi-interpolation operator based on a new transcendental RBF

Mohammad Heidari·Maryam Mohammadi·Stefano De Marchi
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Abstract

It is well-known that the univariate Multiquadric quasi-interpolation operator is constructed based on the piecewise linear interpolation by |x|. In this paper, we first introduce a new transcendental RBF based on the hyperbolic tangent function as a smooth approximant to f(r)=r with higher accuracy and better convergence properties than the multiquadric. Then Wu-Schaback's quasi-interpolation formula is rewritten using the proposed RBF. It preserves convexity and monotonicity. We prove that the proposed scheme converges with a rate of O(h^2). So it has a higher degree of smoothness. Some numerical experiments are given in order to demonstrate the efficiency and accuracy of the method.

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Mohammad Heidari, Maryam Mohammadi, Stefano De Marchi. 2021-06-10. A shape preserving quasi-interpolation operator based on a new transcendental RBF. https://arxiv.org/abs/2106.05714

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