Výsledky vyhľadávania - "Thresholding greedy algorithm"

The thresholding greedy algorithm versus approximations with sizes bounded by certain functions f Autor Chu, Hùng Việt

“…Let X be a Banach space and (en)n=1∞ be a basis. For a function f in a large collection F (closed under composition), we define and characterize f-greedy and…”
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Elton's near unconditionality of bases as a threshold-free form of greediness Autor Albiac, Fernando, Ansorena, José L., Berasategui, Miguel

“…Elton's near unconditionality and quasi-greediness for largest coefficients are two properties of bases that made their appearance in functional analysis from…”
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Linear versus nonlinear forms of partial unconditionality of bases Autor Albiac, Fernando, Ansorena, José L., Berasategui, Miguel

“…The main results in this paper contribute to bringing to the fore novel underlying connections between the contemporary concepts and methods springing from…”
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Twenty-five years of greedy bases Autor Albiac, Fernando, Ansorena, José L., Temlyakov, Vladimir

“…Although the basic idea behind the concept of a greedy basis had been around for some time, the formal development of a theory of greedy bases was initiated in…”
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Counterexamples in isometric theory of symmetric and greedy bases Autor Albiac, Fernando, Ansorena, José L., Blasco, Óscar, Chu, Hùng Việt, Oikhberg, Timur

“…We continue the study initiated in Albiac and Wojtaszczyk (2006) of properties related to greedy bases in the case when the constants involved are sharp, i.e.,…”
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Bidemocratic Bases and Their Connections with Other Greedy-Type Bases Autor Albiac, Fernando, Ansorena, José L., Berasategui, Miguel, Berná, Pablo M., Lassalle, Silvia

“…In nonlinear greedy approximation theory, bidemocratic bases have traditionally played the role of dualizing democratic, greedy, quasi-greedy, or almost greedy…”
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On some characterizations of greedy-type bases Autor Berná, Pablo M., Chu, Hùng Việt

“…In 1999, S. V. Konyagin and V. N. Temlyakov introduced the so-called Thresholding Greedy Algorithm. Since then, there have been many interesting and useful…”
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Characterization of 1-quasi-greedy bases Autor Albiac, F., Ansorena, J.L.

“…In this note we continue the study initiated in Albiac and Wojtaszczyk (2006) of greedy-like bases in the “isometric case”, i.e., in the case that the…”
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Characterization of greedy bases in Banach spaces Autor Berná, Pablo M., Blasco, Óscar

“…We shall present a new characterization of greedy bases and 1-greedy bases in terms of certain functionals defined using distances to one dimensional subspaces…”
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Existence of Almost Greedy Bases in Mixed-Norm Sequence and Matrix Spaces, Including Besov Spaces Autor Albiac, Fernando, Ansorena, José L., Bello, Glenier, Wojtaszczyk, Przemysław

“…We prove that the sequence spaces ℓ p ⊕ ℓ q and the spaces of infinite matrices ℓ p ( ℓ q ) , ℓ q ( ℓ p ) and ( ⨁ n = 1 ∞ ℓ p n ) ℓ q , which are isomorphic to…”
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On sequential greedy-type bases: On sequential greedy-type bases Autor Berasategui, Miguel, Berná, Pablo M., Chu, Hùng Việt

“…It is known that a basis is almost greedy if and only if the thresholding greedy algorithm gives essentially the smallest error term compared to errors from…”
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On approximation spaces and Greedy-type bases Autor Berná, Pablo M., Chu, Hùng Việt, Hernández, Eugenio

“…The purpose of this paper is to introduce ω -Chebyshev–Greedy and ω -partially greedy approximation classes and study their relation with ω -approximation…”
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Lebesgue inequalities for the greedy algorithm in general bases Autor Berná, Pablo M., Blasco, Óscar, Garrigós, Gustavo

“…We present various estimates for the Lebesgue type inequalities associated with the thresholding greedy algorithm, in the case of general bases in Banach…”
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On Weighted Greedy-Type Bases Autor Chu, Hùng Việt

“…We study weights for the thresholding greedy algorithm, aiming to extend previous work on sequential weights ς on N to weights ω on P ( N ) . We revisit major…”
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Characterization of 1-almost greedy bases Autor Albiac, F., Ansorena, J. L.

“…This article closes the cycle of characterizations of greedy-like bases in the “isometric” case initiated in Albiac and Wojtaszczyk (J. Approx. Theory…”
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On consecutive greedy and other greedy-like type of bases Autor Berasategui, Miguel, Berná, Pablo M., Chu, Hùng Việt

“…We continue our study of the thresholding greedy algorithm when we restrict the vectors involved in our approximations so that they either are supported on…”
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Conditional Quasi-Greedy Bases in Non-superreflexive Banach Spaces Autor Albiac, Fernando, Ansorena, José L., Wojtaszczyk, Przemysław

“…For a conditional quasi-greedy basis B in a Banach space, the associated conditionality constants k m [ B ] verify the estimate k m [ B ] = O ( log m ) …”
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Characterization of Weight-Semi-greedy Bases Autor Berná, Pablo Manuel

“…One classical result in greedy approximation theory is that almost-greedy and semi-greedy bases are equivalent in the context of Schauder bases in Banach…”
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Lebesgue inequalities for Chebyshev thresholding greedy algorithms Autor Berná, P. M., Blasco, Ó., Garrigós, G., Hernández, E., Oikhberg, T.

“…We establish estimates for the Lebesgue parameters of the Chebyshev weak thresholding greedy algorithm in the case of general bases in Banach spaces. These…”
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Lebesgue-Type Inequalities for Quasi-greedy Bases Autor Garrigós, Gustavo, Hernández, Eugenio, Oikhberg, Timur

“…We show that, for quasi-greedy bases in real or complex Banach spaces, an optimal bound for the ratio between greedy N -term approximation ∥ x − G N x ∥ and…”
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