Minimum rank and maximum eigenvalue multiplicity of symmetric tree sign patterns
نویسندگان
چکیده
منابع مشابه
Rational realization of maximum eigenvalue multiplicity of symmetric tree sign patterns
Abstract. A sign pattern is a matrix whose entries are elements of {+,−, 0}; it describes the set of real matrices whose entries have the signs in the pattern. A graph (that allows loops but not multiple edges) describes the set of symmetric matrices having a zero-nonzero pattern of entries determined by the absence or presence of edges in the graph. DeAlba et al. [3] gave algorithms for the co...
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The minimum rank of a sign pattern matrix is defined to be the smallest possible rank over all real matrices having the given sign pattern. The maximum nullity of a sign pattern is the largest possible nullity over the same set of matrices, and is equal to the number of columns minus the minimum rank of the sign pattern. Definitions of various graph parameters that have been used to bound maxim...
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The minimum rank of a sign pattern matrix is defined to be the smallest possible rank over all real matrices having the given sign pattern. The maximum nullity of a sign pattern is the largest possible nullity over the same set of matrices, and is equal to the number of columns minus the minimum rank of the sign pattern. Definitions of various graph parameters that have been used to bound maxim...
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متن کاملMinimum ranks of sign patterns via sign vectors and duality
A sign pattern matrix is a matrix whose entries are from the set {+,−, 0}. The minimum rank of a sign pattern matrix A is the minimum of the ranks of the real matrices whose entries have signs equal to the corresponding entries of A. It is shown in this paper that for any m×n sign pattern A with minimum rank n− 2, rational realization of the minimum rank is possible. This is done using a new ap...
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ژورنال
عنوان ژورنال: Linear Algebra and its Applications
سال: 2006
ISSN: 0024-3795
DOI: 10.1016/j.laa.2006.02.018