Approximating partial derivatives of first and second order by quadratic spline quasi-interpolants on uniform meshes
نویسندگان
چکیده
Given a bivariate function f defined in a rectangular domain Ω, we approximate it by a C1 quadratic spline quasi-interpolant (QI) and we take partial derivatives of this QI as approximations to those of f. We give error estimates and asymptotic expansions for these approximations. We also propose a simple algorithm for the determination of stationary points, illustrated by a numerical example. © 2007 IMACS. Published by Elsevier B.V. All rights reserved.
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عنوان ژورنال:
- Mathematics and Computers in Simulation
دوره 77 شماره
صفحات -
تاریخ انتشار 2008