Norm preserving Matrix properties

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Norm-2 preserving can be done using unitary/orthogonal matrix: $A^*A = I => ||Ax|| = ||x||$

What is the matrix other than identity matrix that can preserve other norms ( norm-1, norm-inf) ?

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My intuition says that you are limited to +1 or -1 on the diagonal if it should hold for all x and all norms.

General rotations won't survive taxi distance or max in $R^2$ already.