Optimal H/sup infinity / norm computation for multivariable systems with multiple zeros

B. C.Chang and J.B. Peason's (see ibid., vol. AC-29, p.880-7, Oct. 1984) computation of the optimal H/sup infinity / norm is generalized to the case with multiple right half-plane zeros. D. Sarason's (1967) interpolation theory is used to reduce the problem to a simple eigenvalue or singular-value computation.<
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