Symmetrize

Symmetrize[tensor, sym] returns the symmetrization of tensor under the symmetry sym.

Examples

Symmetrize a matrix:

Symmetrize[{{a, b}, {c, d}}]
(* {{a, (b + c)/2}, {(b + c)/2, d}} *)

Antisymmetrize:

Symmetrize[{{a, b}, {c, d}}, Antisymmetric[{1, 2}]]
(* {{0, (b - c)/2}, {(-b + c)/2, 0}} *)

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