A posteriori Error Bounds for the Zeros of a Polynomial
نویسنده
چکیده
An algorithm for the computation of error bounds for the zeros of a polynomial is described. This algorithm is derived by applying Rouch6's theorem to a Newton-like interpolation formula for the polynomial, and so it is suitable in the case where the approximations to the zeros of the polynomial are computed successively using deflation. Confluent and clustered approximations are handled easily. However bounds for the local rouding errors in deflation, e.g. in Homer's scheme, must be known. In practical application the method can, especially in some ill-conditioned cases, compete with other known estimates.
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تاریخ انتشار 2005