Citation: | Na Chen, Deliang Zhu. THE GREEDY RANDOMIZED EXTENDED KACZMARZ ALGORITHM FOR NOISY LINEAR SYSTEMS[J]. Journal of Applied Analysis & Computation, 2023, 13(2): 913-927. doi: 10.11948/20220230 |
For solving the noisy linear systems, we propose a new greedy randomized extended Kaczmarz algorithm by introducing an effective greedy criterion for selecting the working rows and a randomized orthogonal projection for reducing the influence of the noisy term. We prove that the solution of the proposed greedy randomized extended Kaczmarz algorithm converges in expectation to the least squares solution of the given linear system. Theoretical analysis indicate that the convergence rate of the greedy randomized extended Kaczmarz algorithm is much faster than the randomized extended Kaczmarz method, and numerical results also show that the proposed greedy randomized extended Kaczmarz algorithm is superior to the randomized extended Kaczmarz method. Moreover, for noisy linear systems, the proposed algorithm is more effcient than the greedy randomized Kaczmarz algorithm.
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RSE versus IT for GREK and REK with
RSE versus IT for GREK and REK with
RSE versus IT for GREK, GRK and REK with noisy linear systems with noisy level 0.2 (Row 1), 0.3 (Row 2), 0.4 (Row 3) and 0.5 (Row 4). Left: The results for overdetermined systems. Right: The results for underdetermined systems.