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Section 40.3 Terminology and notation
- orthogonally diagonalizable
a real square matrix
\(A\) for which there exists an orthogonal matrix
\(P\) such that
\(\inv{P} A P = \utrans{P} A P\) is diagonal
- unitarily diagonalizable
a complex square matrix
\(A\) for which there exists a unitary matrix
\(U\) such that
\(\inv{U} A U = \adjoint{U} A U\) is diagonal
- normal matrix
a complex square matrix which commutes with its adjoint; i.e. a complex matrix
\(A\) for which
\(\adjoint{A} A = A \adjoint{A}\)
