Abstract
We describe regularizing iterative methods for the solution of large ill-conditioned linear systems of equations that arise from the discretization of linear ill-posed problems. The regularization is specified by a filter function of Gaussian type. A parameter μ determines the amount of regularization applied. The iterative methods are based on a truncated Lanczos decomposition and the filter function is approximated by a linear combination of Lanczos polynomials. A suitable value of the regularization parameter is determined by an L-curve criterion. Computed examples that illustrate the performance of the methods are presented.
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Calvetti, D., Reichel, L. Lanczos-Based Exponential Filtering for Discrete Ill-Posed Problems. Numerical Algorithms 29, 45–65 (2002). https://doi.org/10.1023/A:1014899604567
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DOI: https://doi.org/10.1023/A:1014899604567