Abstract
Nonlinear mean — square approximation requires the development of methods which are different from the tools commonly used in nonlinear Chebyshev approximation. This is illustrated by considering approximation by rationals in the L2 -Norm. Typical for the whole situation are two facts. On one hand we have almost always uniqueness of the global solution, on the other hand there is no bound on the number of local solutions.
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Braess, D. (1976). Über das Anzahlproblem Bei der Rationalen L2 — Approximation. In: Collatz, L., Werner, H., Meinardus, G. (eds) Numerische Methoden der Approximationstheorie/Numerical Methods of Approximation Theory. International Series of Numerical Mathematics, vol 30. Birkhäuser, Basel. https://doi.org/10.1007/978-3-0348-7692-6_5
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DOI: https://doi.org/10.1007/978-3-0348-7692-6_5
Publisher Name: Birkhäuser, Basel
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