Tree sign pattern matrices that require zero eigenvalues
نویسندگان
چکیده
منابع مشابه
Sign Pattern Matrices that Admit P0 Matrices
A P0-matrix is a real square matrix all of whose principle minors are nonnegative. In this paper, we consider the class of P0-matrix. Our main aim is to determine which sign pattern matrices are admissible for this class of real matrices. Keywords—Sign pattern matrices, P0 matrices, graph, digraph
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متن کاملPrimitive Zero-Symmetric Sign Pattern Matrices with Zero Diagonal Attaining the Maximum Base
A sign pattern matrix or sign pattern A is a matrix whose entries are from the set {1,−1, 0}. Notice that for a square sign pattern matrixA, in the computation of the signs of the entries of the power A, an ambiguous sign may arise when a positive sign is added to a negative sign. So a new symbol # was introduced in 1 to denote such an ambiguous sign. The powers of a square sign pattern have be...
متن کاملSign patterns that require eventual exponential nonnegativity
Sign patterns that require exponential nonnegativity are characterized. A set of conditions necessary for a sign pattern to require eventual exponential nonnegativity are established. It is shown that these conditions are also sufficient for an upper triangular sign pattern to require eventual exponential nonnegativity and it is conjectured that these conditions are both necessary and sufficien...
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ژورنال
عنوان ژورنال: Bulletin of the Australian Mathematical Society
سال: 1997
ISSN: 0004-9727,1755-1633
DOI: 10.1017/s0004972700030550