Gersgorin and His Circles

Contains numerous simple examples and illustrative diagrams…For anyone seeking information about eigenvalue inclusion theorems, this book will be a great reference. –Mathematical Reviews This book studies the original results, and their extensions, of the Russian mathematician S.A. GerA!gorin who wrote a seminal paper in 1931 on how to easily obtain estimates of all n eigenvalues (characteristic values) of any given n-by-n complex matrix.