On skew-Hamiltonian matrices and their Krylov-Lagrangian subspaces
نویسندگان
چکیده
It is a well-known fact that the Krylov space K j ( H , x ) generated by skew-Hamiltonian matrix ? R 2 n × and some isotropic for any N . For given subspace L ? of dimension —which called Lagrangian subspace—the question whether can be as considered. The affine variety HK all matrices generate analyzed. Existence uniqueness results are proven, found with minimal 2-norm, Frobenius norm prescribed eigenvalues in identified. Some applications presented given.
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ژورنال
عنوان ژورنال: Linear Algebra and its Applications
سال: 2021
ISSN: ['1873-1856', '0024-3795']
DOI: https://doi.org/10.1016/j.laa.2020.11.021