Yauhen Yakimenka

Thanks, Jaromił.(Sorry, I thought I posted my reply on Friday but now I see that I actually didn't.) Your problem is an LP. Does your statement mean that you know that there is an infinite number ...

Hi Matthias, Thanks for the detailed answer. I will check further sensitivity analysis. Kind regards,/Y.

By the way, why is that you suggest to add the new unequality constraint? Since it was an optimal value, we have that for any feasible solution, $$c^T x \ge c^*$$ Should the new constraint be just ...

P.S. How do you type mutliline formulas here? I can't figure it out and don't see any information on how to type Latex here... :)  

Hi, Matthias, That's very simple and elegant solution. Thanks! Regards,/Y.  

I will try my luck with callbacks :) Thanks!

Yep, this seems to be exactly what I need. Thanks, Eli! /Y.

Okay, I think I found the solution here: https://www.gurobi.com/documentation/9.0/refman/start.html If you want to diagnose an infeasible MIP start, you can try fixing the variables in the model to...

I have a (complete) solution which (I believe) satisfies the constraints of my model - but its objective is far from optimal. After creating the variables of the model, I set the variables by calls...

Okay, I perhaps better post it as a separate question as it might be useful for other users too.