mwette@mr-ed.jpl.nasa.gov (Matt Wette) (12/22/90)
This article concerns the problem of finding two orthogonal matrices Q and Z such that Q'*A*Z is in upper real Schur form Q'*B*Z is upper triangular where A and B are square matrices and ' denotes transpose. I have encountered problems with the EISPACK routine QZIT not converging. The problem I am trying to solve is of order 18 and a `relative Crawford number' for the problem, given by evaluation of the Matlab expression cond(A/norm(A) + j*B/norm(B)), is about 10^2. Does anyone know of software which is a better implementation of (a variant of) the QZ algorithm and/or a better working algorithm for solving the same problem? Matt -- _________________________________________________________________ Matthew R. Wette | Jet Propulsion Laboratory, 198-326 mwette@csi.jpl.nasa.gov | 4800 Oak Grove Dr, Pasadena,CA 91109 -----------------------------------------------------------------