Upper and lower bounds for eigenvalues by finite difference methods
نویسندگان
چکیده
منابع مشابه
Upper and lower bounds for numerical radii of block shifts
For an n-by-n complex matrix A in a block form with the (possibly) nonzero blocks only on the diagonal above the main one, we consider two other matrices whose nonzero entries are along the diagonal above the main one and consist of the norms or minimum moduli of the diagonal blocks of A. In this paper, we obtain two inequalities relating the numeical radii of these matrices and also determine ...
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ژورنال
عنوان ژورنال: Communications on Pure and Applied Mathematics
سال: 1956
ISSN: 0010-3640,1097-0312
DOI: 10.1002/cpa.3160090329