Eigenvalues after multiplication with permutation matrix.

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Let $A$ be a diagonalizable matrix, and $P$ be permutation matrix of same size. Does $A$ and $PAP$ have the same eigenvalues (or characteristic polynomial)?

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Since $P^\top = P^{-1}$ (it is not the case that $P = P^{-1}$), it follows that the matrices $A$ and $P^\top A P$ have the same characteristic polynomial and hence eigenvalues (the latter is called a permutation similarity).