We construct bounded polynomial operators, similar to the classical de la Valle e Poussin operators in the theory of Fourier series, which preserve polynomials of a certain degree, but are defined in terms of the values of the function rather than its Fourier coefficients.
Refinable interpolatory and quasi-interpolatory operators
โ Scribed by Laura Gori; Francesca Pitolli; Elisabetta Santi
- Publisher
- Elsevier Science
- Year
- 2007
- Tongue
- English
- Weight
- 448 KB
- Volume
- 75
- Category
- Article
- ISSN
- 0378-4754
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โฆ Synopsis
In this paper, we present a new class of operators, which are refinable, quasi-interpolatory and satisfy some interpolation conditions. The refinability is achieved by using as functional bases the B-bases corresponding to totally positive refinable functions. We analyze the main properties of the constructed refinable operators and give some convergence results. Some examples are also displayed.
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