# Symmetric nonnegative realization of spectra

@article{Soto2007SymmetricNR, title={Symmetric nonnegative realization of spectra}, author={Ricardo L. Soto and Oscar Rojo and Julio Moro and Alberto M. Borobia}, journal={Electronic Journal of Linear Algebra}, year={2007}, volume={16}, pages={1} }

A perturbation result, due to R. Rado and presented by H. Perfect in 1955, shows how to modify r eigenvalues of a matrix of order n, r ≤ n, via a perturbation of rank r, without changing any of the n − r remaining eigenvalues. This result extended a previous one, due to Brauer, on perturbations of rank r = 1. Both results have been exploited in connection with the nonnegative inverse eigenvalue problem. In this paper a symmetric version of Rado’s extension is given, which allows us to obtain a…

## 36 Citations

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