Weighted extremal domains and best rational approximation
نویسندگان
چکیده
منابع مشابه
Weighted Extremal Domains and Best Rational Approximation
Let f be holomorphically continuable over the complex plane except for finitely many branch points contained in the unit disk. We prove that best rational approximants to f of degree n, in the L2-sense on the unit circle, have poles that asymptotically distribute according to the equilibrium measure on the compact set outside of which f is single-valued and which has minimal Green capacity in t...
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We propose a practical algorithm of best rational approximation of a given order to a function in the Hardy H space on the unit circle or on the real line. The type approximation is proved to be equivalent with Blaschke form approximation. The algorithm is called Cyclic AFD as it adaptively selects one parameter during each cycle based on the Maximal Selection Principle used in adaptive Fourier...
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ژورنال
عنوان ژورنال: Advances in Mathematics
سال: 2012
ISSN: 0001-8708
DOI: 10.1016/j.aim.2011.09.005