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On the convergence of greedy algorithms for initial segments of the Haar basis

Published online by Cambridge University Press:  15 January 2010

S. J. DILWORTH
Affiliation:
Department of Mathematics, University of South Carolina, Columbia, SC 29208, U.S.A. e-mail: dilworth@math.sc.edu
E. ODELL
Affiliation:
Department of Mathematics, The University of Texas, 1 University Station C1200, Austin, TX 78712, U.S.A. e-mail: odell@math.utexas.edu
TH. SCHLUMPRECHT
Affiliation:
Department of Mathematics, Texas A & M University, College Station, TX 78743, U.S.A. e-mail: schlump@math.tamu.edu
ANDRÁS ZSÁK
Affiliation:
Department of Mathematics and Statistics, Fylde College, Lancaster University, Lancaster LA1 4YF. Peterhouse College, Cambridge, CB2 1RD. e-mail: A.Zsak@dpmms.cam.ac.uk

Abstract

We consider the X-Greedy Algorithm and the Dual Greedy Algorithm in a finite-dimensional Banach space with a strictly monotone basis as the dictionary. We show that when the dictionary is an initial segment of the Haar basis in Lp[0, 1] (1 < p < ∞) then the algorithms terminate after finitely many iterations and that the number of iterations is bounded by a function of the length of the initial segment. We also prove a more general result for a class of strictly monotone bases.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 2010

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References

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