Best one-sided L1 approximation to the Heaviside and sign functions
نویسندگان
چکیده
We find the polynomials of the best one-sided approximation to the Heaviside and sign functions. The polynomials are obtained by Hermite interpolation at the zeros of some Jacobi polynomials. Also we give an estimate of the error of approximation and characterize the extremal points of the convex set of the best approximants. c ⃝ 2012 Elsevier Inc. All rights reserved.
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ورودعنوان ژورنال:
- Journal of Approximation Theory
دوره 164 شماره
صفحات -
تاریخ انتشار 2012