Eigenvalues of the Sum of Matrices from Unitary Similarity Orbits
نویسندگان
چکیده
Abstract Let A and B be n×n complex matrices. Characterization is given for the set E(A,B) of eigenvalues of matrices of the form UAU + V BV for some unitary matrices U and V . Consequences of the results are discussed and computer algorithms and programs are designed to generate the set E(A,B). The results refine those of Wielandt on normal matrices. Extensions of the results to the sum of matrices from three or more unitary similarity orbits are also considered.
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عنوان ژورنال:
- SIAM J. Matrix Analysis Applications
دوره 30 شماره
صفحات -
تاریخ انتشار 2008