Natural Science, Mathematics, 2025
ON THE TWO-LEVEL PRECONDITIONING IN LEAST SQUARES METHOD
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Submitted: 2025-02-17; Published: 2025-02-17
© 2025 by author(s) and The Gufo Inc.
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Abstract
In the present paper an approach to construct algebraic two-level preconditioners for the matrices of normal systems arising in data fitting by least squares method with piecewise linear basis functions is proposed. The approach is based on using hierarchical grids with their subdivision into substructures and corresponding partition of the matrices. Estimates for condition numbers of preconditioned matrices are obtained.