[Scip] Upper triangular or symmetric matrix for quadratic constraints

[Ramón Casero Cañas]

Dear all,

I have a question about how to format quadratic constraints in SCIP.

Say we have [x y] as variables, and we want the constraint 0 <= xy <= 5.

Is it better to aim for a symmetric matrix

0 <= [x y] [0.0  0.5] [x] <=5
               [0.5  0.0] [y]

or for an upper triangular

0 <= [x y] [0.0  1.0] [x] <=5
               [0.0  0.0] [y]

or it doesn't matter? Theoretically they both produce the same constraint,
but maybe there are some numerical issues or  implementation details in
SCIP by which one should be preferred.

Many thanks,

Ramon.
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