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arXiv · 1708.06648

A note on matrices mapping a positive vector onto its element-wise inverse

Sébastien Labbé
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Abstract

For any primitive matrix $M\in\mathbb{R}^{n\times n}$ with positive diagonal entries, we prove the existence and uniqueness of a positive vector $\mathbf{x}=(x_1,\dots,x_n)^t$ such that $M\mathbf{x}=(\frac{1}{x_1},\dots,\frac{1}{x_n})^t$. The contribution of this note is to provide an alternative proof of a result of Brualdi et al. (1966) on the diagonal equivalence of a nonnegative matrix to a stochastic matrix.

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Sébastien Labbé. 2017-08-21. A note on matrices mapping a positive vector onto its element-wise inverse. https://doi.org/10.1016/j.jmaa.2018.03.016

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