hess(G)

NAME
hess - Hessenberg form

CALLING SEQUENCE
H = hess(A)
[U,H] = hess(A)

PARAMETERS

A   : real or complex square matrix

H   : real or complex square matrix

U   : orthogonal or unitary square matrix

DESCRIPTION
produces a unitary matrix U and a Hessenberg matrix H so
that A = U*H*U' and U'*U = Identity.  By itself, hess(A)
returns H.

The Hessenberg form of a matrix is zero below the first
subdiagonal. If the matrix is symmetric or
Hermitian, the form is tridiagonal.

SEE ALSO
qr, contr.