Spectral Radius

Let ${\hbox{\sf A}}$ be an $n\times n$ Matrix with Complex or Real elements with Eigenvalues $\lambda_1$, ..., $\lambda_n$. Then the spectral radius $\rho({\hbox{\sf A}})$ of ${\hbox{\sf A}}$ is

$$\rho({\hbox{\sf A}})=\max_{1\leq i\leq n} \vert\lambda_i\vert.$$

References

Gradshteyn, I. S. and Ryzhik, I. M. Tables of Integrals, Series, and Products, 5th ed. San Diego, CA: Academic Press, pp. 1115-1116, 1979.