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On normal matrices with normal principal submatrices
Let A be a normal n×n matrix. This paper discusses in detail under what conditions and in what way A can be dilated to a normal matrix of order n+1 or n+2. Bibliography: 4 titles.
Some observations on the Youla form and conjugate-normal matrices
Abstract Two square complex matrices A , B are said to be unitarily congruent if there is a unitary matrix U such that A  =  UBU T . The Youla form is a canonical form under unitary congruence. WeExpand
Conjugate-normal matrices: A survey
Conjugate-normal matrices play the same important role in the theory of unitary congruence as the conventional normal matrices do with respect to unitary similarities. However, unlike the latter, theExpand
Hamiltonian square roots of skew-Hamiltonian matrices revisited
Abstract Recently, H. Fassbender et al. [Linear Algebra Appl. 287 (1999) 125] proved the following theorem: Every real skew-Hamiltonian matrix W has a real Hamiltonian square root H, i.e., H 2 =W. WeExpand
A numerical algorithm for solving the matrix equation AX + XTB = C1
An algorithm of the Bartels-Stewart type for solving the matrix equation AX + XTB = C is proposed. By applying the QZ algorithm, the original equation is reduced to an equation of the same typeExpand
Unitary congruence automorphisms of the space of Toeplitz matrices
Let be the set of Toeplitz matrices. We describe the matrices in the unitary group such that
Symmetrization of complex normal matrices