Hi everyone, I just read the documentation and noticed that there is, as I understood it, a mathematical mistake (and also at the execution).
If you look at this section <https://docs.sympy.org/latest/modules/assumptions/predicates.html#sympy.assumptions.predicates.matrices.SymmetricPredicate>, it seems to assert that the product (not the Hadamard product, but usual one) of two symmetric matrices is also symmetric, which is True if and only if both matrices commutes; but as their shape is (in the example) defined as 2x2, they do not necessarily. from sympy import Q, ask, MatrixSymbol, Equality X = MatrixSymbol('X', 2, 2) Z = MatrixSymbol('Z', 2, 2) print(ask(Q.symmetric(X * Z), Q.symmetric(X) & Q.symmetric(Z))) # True print(ask(Equality(X * Z, Z * X), Q.symmetric(X) & Q.symmetric(Z))) # False Here both output should give False. Best regards, F. Périat -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/sympy/d029d408-66cb-4531-a548-b7e455a0387dn%40googlegroups.com.
