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A counterexample to a result concerning controlled approximation. (English) Zbl 0592.41029
Summary: A result of Strang and Fix states that if the order of controlled approximation from a collection of locally supported elements is k, then there is a linear combination $$\Omega$$ of those elements and their translates such that any polynomial of degree less than k can be reproduced by $$\Omega$$ and its translates. This paper gives a counterexample to their result.

##### MSC:
 41A29 Approximation with constraints
##### Keywords:
controlled approximation; counterexample
Full Text:
##### References:
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