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arXiv · 1911.03715

Twists of two or multiple idempotent matrices

Yongge Tian
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Abstract

In this article, we revisit some block matrix construction methods and use them to derive various general expansion formulas for calculating the ranks of matrix expressions. As applications, we derive a variety of interesting rank equalities for matrix expressions composed by idempotent matrices, and present their applications in the characterization of some matrix equalities for generalized inverses of partitioned matrices.

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Yongge Tian. 2019-11-09. Twists of two or multiple idempotent matrices. https://arxiv.org/abs/1911.03715

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