Lihua Zhang

most citedMinimum ranks of sign patterns via sign vectors and duality

3 citations · 3 across the 4 of their papers we have counts for

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math.CO2017

Sign patterns that require $H_{n}$ exist for each $n \geq 4$

Wei Gao, Zhongshan Li, Lihua Zhang

The refined inertia of a square real matrix $A$ is the ordered $4$ -tuple $(n_{+}, n_{-}, n_{z}, 2 n_{p})$ , where $n_{+}$ (resp., $n_{-}$ ) is the number of eigenvalues of $A$ with positive (resp…

math.CO2013

Sign patterns with minimum rank 3 and point-line configurations

Guangming Jing, Wei Gao, Yubin Gao +4

A \emph{sign pattern (matrix)} is a matrix whose entries are from the set ${+, -, 0}$ . The \emph{minimum rank} (respectively, \emph{rational minimum rank}) of a sign pattern matr…

math.CO2013★ 3 cited

Minimum ranks of sign patterns via sign vectors and duality

Marina Arav, Frank J. Hall, Zhongshan Li +3

A {\it 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…

math.CO2013

The minimum rank of a sign pattern matrix with a 1-separation

Marina Arav, Frank J. Hall, Zhongshan Li +3

A sign pattern matrix is a matrix whose entries are from the set ${+, -, 0}$ . If $A$ is an $m \times n$ sign pattern matrix, the qualitative class of $A$ , denoted $Q (A)$ , is the set…

Sign patterns that require Hn​ exist for each n≥4

Sign patterns with minimum rank 3 and point-line configurations

Minimum ranks of sign patterns via sign vectors and duality

The minimum rank of a sign pattern matrix with a 1-separation

Sign patterns that require $H_{n}$ exist for each $n \geq 4$