On the eigenvalues and eigenvectors of nonsymmetric saddle point matrices preconditioned by block triangular matrices
نویسنده
چکیده
Block lower triangular and block upper triangular matrices are popular preconditioners for nonsymmetric saddle point 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 systems are related. Nonsingular saddle point matrices of the form
منابع مشابه
Pestana, Jennifer (2014) On the eigenvalues and eigenvectors of block triangular preconditioned block matrices. SIAM Journal on Matrix
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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