A root-distribution criterion for an interval polynomial in a sector
A. Levkovich · IMA Journal of Mathematical Control and Information · 1996
A simple test is proposed for checking whether a given interval polynomial ℱ of degree n has robust root distribution with respect to a given symmetric sector in the complex plane. The test amounts to checking the real roots of at most 2n real polynomials with fixed coefficients, of degree n. The test is based on a detailed analysis of the value set ℱ(s) as s travels along the sector boundary. A simple algorithm for implementing this test, and an example, are also provided.