On matrices for which norm bounds are attained
نویسندگان
چکیده
Let kAkp q be the norm induced on the matrix A with n rows and m columns by the H older p and q norms on R and R or C and C respectively It is easy to nd an upper bound for the ratio kAkr s kAkp q In this paper we study the classes of matrices for which the upper bound is attained We shall show that for xed A attainment of the bound depends only on the signs of r p and s q Various criteria depending on these signs are obtained For the special case p q the set of all matrices for which the bound is attained is generated by means of singular value decompositions
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تاریخ انتشار 1997