You can use the “Incumbent” and “Incumbent” suffix to retrieve the best known solution and the  LP bound, then use them to calculate the GAP and assign it to a parameter.

MpGap :=(abs(MathProgram.Incumbent - MathProgram.bestbound)/$abs(MathProgram.Incumbent)) * 100;

Hello @deannezhang,

Thank you for the method to calculate the gap. For solving time, is there a way to retrieve it?

Thank you.

Yes, you can use the “SolutionTime” suffix. For other suffix and callback functions, you can refer to the AIMMS Language reference, part “Suffices and Callbacks”.

Hi @deannezhang,

Thanks a lot….