Two results are proved which concern Riesz points of upper triangular operator matrices. Applications are made to questions involving when Weyl's Theorem holds for an upper triangular operator matrix.

Of particular interest are canonical forms which, by definition, have a D-matrix consisting of the nontrivial invariants. Among these is a family of triangular forms, which, besides being canonical, ...

Helper function MatInverseUpperTri () is used to compute the inverse of the R matrix that results from QR decomposition. The technique used to compute the inverse of an upper triangular or lower ...