Michel Soares
Optimization Specialist at BITKA Analytics
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Recent activity by Michel Soares-
Hi Nima, From the logs, looking only at possible parameter changes, I would suggest trying Presolve = 2 and MIPFocus = 1. Also, updating your Gurobi to 11.0 might improve your results as well.
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Hi Laaziz, I cannot see how that would be possible, I believe it would take a in-depth look to understand it. Can you share the logs and the LP file?
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MIQCP is a convex optimization problem with integer variables. All convex optimization and integer programming optimization theory still holds and a lot of the technique Gurobi's uses is directly i...
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Hi, Indeed there are additional steps involved in equal constraints. However, I cannot see how it would be better to replace it by two inequalities, it should be worse because it increases the numb...
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As far as I understand, Aggregate and AggFill will mostly remove variables. These are sometimes referred to as "Substitute implied free variables". Disabling Aggregate increases your model solve ti...
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Hi, I am not sure if it would help, but it seems like you do not need Bp[edge], you can use direction_AB and direction_BA instead. It should remove some variables and make your model more dense, wh...
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Hi, You can get the presolved model this way: reduced_model = model.presolve() reduced_model.write("reduced_model.lp") You may be able to directly modify the reduced_model directly as you wish, I h...
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Hi, Could you write Gurobi's logs? There might be more information there regarding the use of warm start, information about your model and how it is solving your LP.
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Hi, The presolve step will usually change your model to another equivalent model that is easier for the solver to find a solution. In this step the number of constraints and variables are usually r...
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Hi, The only way I think of doing this would be to disable all pre-solve parameters except PreDepRow and export the reduced model, comparing to the original model. I have never tried this, but it m...