Pestana, Jennifer (2014) On the eigenvalues and eigenvectors of block triangular preconditioned block matrices. SIAM Journal on Matrix
نویسنده
چکیده
Block lower triangular matrices and block upper triangular matrices are popular preconditioners for 2×2 block matrices. In this note we show that a block lower triangular preconditioner gives the same spectrum as a block upper triangular preconditioner and that the eigenvectors of the two preconditioned matrices are related.
منابع مشابه
On the Eigenvalues and Eigenvectors of Block Triangular Preconditioned Block Matrices
Block lower triangular matrices and block upper triangular matrices are popular preconditioners for 2×2 block matrices. In this note we show that a block lower triangular preconditioner gives the same spectrum as a block upper triangular preconditioner and that the eigenvectors of the two preconditioned matrices are related.
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