Geodesic
Comparison of a pure greedy algorithm with a pure greedy one in a pair of dictionaries
Vestnik Moskovskogo universiteta. Matematika, mehanika, no. 2 (2023), pp. 3-11 
A. S. Orlova. Comparison of a pure greedy algorithm with a pure greedy one in a pair of dictionaries. Vestnik Moskovskogo universiteta. Matematika, mehanika, no. 2 (2023), pp. 3-11. http://geodesic.mathdoc.fr/item/VMUMM_2023_2_a0/
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Voir la notice de l'article provenant de la source Math-Net.Ru

In this paper, we compare the standard Pure Greedy Algorithm (PGA) with its modification — PGA in a pair of dictionaries. We show that PGA in a pair of dictionaries converges in certain cases in a finite number of steps, while the standard PGA for each individual dictionary has non-zero remainders at each step; at the same time, in certain cases the opposite holds true. Similarly, for the comparison of PGA in a pair of dictionaries vs standard PGA in a union of these dictionaries both situations are possible. For the convergence rate, we also prove that in certain cases PGA in a pair of dictionaries can be faster, and in certain cases can be slower than the standard PGA in individual dictionaries.

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