A real QZ algorithm for structured companion pencils
نویسندگان
چکیده
منابع مشابه
Optimal Scaling of Companion Pencils for the QZ-Algorithm∗†
Computing roots of a monic polynomial may be done by computing the eigenvalues of the corresponding companion matrix using for instance the well-known QR-algorithm. We know this algorithm to be backward stable since it computes exact eigenvalues of a slightly modified matrix. But it may yield very poor backward errors in the coefficients of the polynomial. In this paper we investigate what can ...
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Let RP be the space of all homogeneous polynomials of degree n in two variables with real coefficients. The standard discriminant Dn+1 ⊂ RP n is Whitney stratified according to the number and the multiplicities of multiple real zeros. A real polynomial pencil, that is, a line L ⊂ RP is called generic if it intersects Dn+1 transversally. Nongeneric pencils form the Grassmann discriminant D2,n+1 ...
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ژورنال
عنوان ژورنال: Calcolo
سال: 2017
ISSN: 0008-0624,1126-5434
DOI: 10.1007/s10092-017-0231-6