# hessenberg

Version:

Converts a matrix to Hessenberg form and returns the unitary transformation matrix. The Hessenberg form of a matrix has elements equal to 0 below the first subdiagonal.

## Syntax

h = hessenberg(a)
[t, h] = hessenberg(a)
Legacy name: hess

## a

Square matrix.

## h

a in Hessenberg form. h is a matrix of the same size as a. If a is a symmetric or Hermitian matrix, h is tridiagonal.

## t

Unitary transformation matrix. t is a matrix of the same size as a.

## Further Information

The Hessenberg matrix h satisfies the following unitary similarity transformation: a = t*h*t' with t*t' = t'*t = eye(size(a)).

A = [2, -4, 7; -1, 9, 0; -4, -7, 3];
[T, H] = hessenberg(A);
C = T*H*T';
D = T*T';

Where This Node Can Run:

Desktop OS: Windows

FPGA: This product does not support FPGA devices