English

A note on the singular value decomposition of idempotent and involutory matrices

Numerical Analysis 2024-03-11 v1 Numerical Analysis

Abstract

It is known that singular values of idempotent matrices are either zero or larger or equal to one \cite{HouC63}. We state exactly how many singular values greater than one, equal to one, and equal to zero there are. Moreover, we derive a singular value decomposition of idempotent matrices which reveals a tight relationship between its left and right singular vectors. The same idea is used to augment a discovery regarding the singular values of involutory matrices as presented in \cite{FasH20}.

Keywords

Cite

@article{arxiv.2403.05214,
  title  = {A note on the singular value decomposition of idempotent and involutory matrices},
  author = {Heike Faßbender and Martin Halwaß},
  journal= {arXiv preprint arXiv:2403.05214},
  year   = {2024}
}