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A Real QZ Algorithm for Structured Companion Pencils

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 نشر من قبل Paola Boito
 تاريخ النشر 2016
  مجال البحث
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We design a fast implicit real QZ algorithm for eigenvalue computation of structured companion pencils arising from linearizations of polynomial rootfinding problems. The modified QZ algorithm computes the generalized eigenvalues of an $Ntimes N$ structured matrix pencil using $O(N)$ flops per iteration and $O(N)$ memory storage. Numerical experiments and comparisons confirm the effectiveness and the stability of the proposed method.

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