Eigenvalues;
Characteristic polynomial;
Condition;
Random matrices;
MATRICES;
D O I:
10.1016/j.jco.2017.03.004
中图分类号:
TP301 [理论、方法];
学科分类号:
081202 ;
摘要:
We prove that the expectation of the logarithm of the condition number of each of the zeros of the characteristic polynomial of a complex standard Gaussian matrix is Omega (n) (the real and imaginary parts of the entries of a Gaussian matrix are independent standard Gaussian random variables). This may provide a theoretical explanation for the common practice in numerical linear algebra that advises against computing eigenvalues via root-finding for characteristic polynomials. (C) 2017 Elsevier Inc. All rights reserved.