HessenbergDecomposition

HessenbergDecomposition[m] gives the Hessenberg decomposition of a numerical matrix m.

Examples

HessenbergDecomposition[{{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}]

{p, h} = HessenbergDecomposition[RandomReal[1, {4, 4}]];
p . h . ConjugateTranspose[p]

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