Chapter 6 Numerical Linear Algebra
This software is designed to illustrate Gerschgorin Circle Theorem. Quoted from 【1】:
Let be an matrix and let denote the circle in the complex plane with center and radius ; that is,
where is used to denote the complex plane. The eigenvalues of are contained within . Moreover, the union of any of these circles that do not intersect the remaining must contain precisely (counting multiplicities) of the eigenvalues.
【1】 R. L. Burden and J. D. Faires, Numerical Analysis, PWS, Boston, 1993.