Three-Precision GMRES-Based Iterative Refinement for Least Squares Problems
نویسندگان
چکیده
منابع مشابه
GMRES Methods for Least Squares Problems
The standard iterative method for solving large sparse least squares problems min ∈Rn ‖ −A ‖2, A ∈ Rm×n is the CGLS method, or its stabilized version LSQR, which applies the (preconditioned) conjugate gradient method to the normal equation ATA = AT . In this paper, we will consider alternative methods using a matrix B ∈ Rn×m and applying the Generalized Minimal Residual (GMRES) method to min ∈R...
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ژورنال
عنوان ژورنال: SIAM Journal on Scientific Computing
سال: 2020
ISSN: 1064-8275,1095-7197
DOI: 10.1137/20m1316822