A Solution of Inverse Eigenvalue Problems for Unitary Hessenberg Matrices
نویسندگان
چکیده
Let H ∈ Cn×n be an n × n unitary upper Hessenberg matrix whose subdiagonal elements are all positive. Partition H as H = H11 H12 H21 H22 , (0.1) where H11 is its k×k leading principal submatrix; H22 is the complementary matrix of H11. In this paper, H is constructed uniquely when its eigenvalues and the eigenvalues of b H11 and b H22 are known. Here b H11 and b H22 are rank-one modifications of H11 and H22 respectively.
منابع مشابه
On an Inverse Eigenvalue Problem for Unitary
We show that a unitary upper Hessenberg matrix with positive subdiago-nal elements is uniquely determined by its eigenvalues and the eigenvalues of a modiied principal submatrix. This provides an analog of a well-known result for Jacobi matrices.
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