Schur-Cohn Algorithm

The Schur-Cohn algorithm is an algorithm that can always be used to decide whether a given polynomial is free of zeros in the closed unit disk (or, using an entire linear transformation, to any other disk in the complex plane). Under certain conditions, the algorithm can also be used to determine the exact number of zeros in a disk (Henrici 1988, p. 494). The method is also useful to control engineers, since it can be used to determine whether a dynamic control system is stable.

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References

Henrici, P. Applied and Computational Complex Analysis, Vol. 1: Power Series-Integration-Conformal Mapping-Location of Zeros. New York: Wiley, pp. 491-494, 1988.

Cite this as:

Weisstein, Eric W. "Schur-Cohn Algorithm." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Schur-CohnAlgorithm.html