矩阵特征值的一类新的存在性区域

A CLASS DOMAIN of NEW EXISTENCE THEOREM FOR EIGENVALUE OF MATRIX

用盖尔斯果林圆盘定理估计矩阵特征值是一个经典的方法，后人对此定理虽有许多改进，例如用卵形区域代替盖氏圆盘，但都显得粗糙．本文的研究得出了一类新的特征值存在区域，它们与盖氏圆盘等方法结合结合能提高估计的精确度。

It is a classical method using the Gersgorin-disc theorem to estimate eigenvalues of a matrix. Many people have made improvements to it. For example, the egg-shaped domain was substitute for the Gersgorin-disc. But it is still seems crude. In this paper, we have obtained a class new existence domain. The precise of estimate eigenvalue will be increased if combine these two methods.