Pseudo-spectral Derivative of Quadratic Quasi-interpolant Splines
نویسنده
چکیده
Abstract. In this paper we propose a local spline method for the approximation of the derivative of a function f . It is based on an optimal spline quasi-interpolant operator Q2, introduced in [12]. Differentiating Q2 f , we construct the pseudo-spectral derivative at the quasi-interpolation knots and the corresponding differentiation matrix. An error analysis is proposed. Some numerical results and comparisons with other known methods are given.
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