  Consider $n \times n$ matrix $A$ and a set $\Lambda$ consisting of $k \le n$
prescribed complex numbers. Lippert (2010) in a challenging article, studied
geometrically the spectral norm distance from $A$ to the set $\Lambda$ and
constructed a perturbation matrix $\Delta$ with minimum spectral norm such that
$A+\Delta$ had $\Lambda$ in its spectrum. This paper presents an easy practical
computational method for constructing the optimal perturbation $\Delta$ by
extending necessary definitions and lemmas of previous works. Also, some
conceivable applications of this issue are provided.
