Hessenberg
ph
'거의' triangular인 행렬
upper Hessenberg: \({\begin{bmatrix}1&4&2&3\\3&4&1&7\\0&2&3&4\\0&0&1&3\\\end{bmatrix}}\)
lower Hessenberg: \({\begin{bmatrix}1&2&0&0\\5&2&3&0\\3&4&3&7\\5&6&1&1\\\end{bmatrix}}\)
'거의' triangular인 행렬
upper Hessenberg: \({\begin{bmatrix}1&4&2&3\\3&4&1&7\\0&2&3&4\\0&0&1&3\\\end{bmatrix}}\)
lower Hessenberg: \({\begin{bmatrix}1&2&0&0\\5&2&3&0\\3&4&3&7\\5&6&1&1\\\end{bmatrix}}\)