Tobias Achterberg

The condition number "kappa" is a property of a square matrix. So, there is not a single "kappa" for your model, but any subset of the columns of cardinality equal to the number of rows yields one ...

This is weird. Are you saying that for the exact same input (same model data, same parameter settings) and the exact same hardware and operating system, you are seeing two runs where in one run it ...

We use orbital fixing plus orbital probing. There is the "Symmetry" parameter which allows you to use symmetry breaking more aggressively. This basically adjust some limits on how much effort is sp...

General Constraints are internally translated into linear and SOS constraints, depending on the General Constraint type. If you use the same linearization yourself, there should be no structural pe...

It is a bit strange that the *.lp file is written with your names, because the LP file writer is using the exact same method to check variable names as the *.sol file writer. Note also that you sho...

My guess is that you have at least one variable name with some non-standard character (like a space or a Greek letter), and thus Gurobi decides that it cannot produce a *.sol that can already be re...

Sometimes it helps to use the feasRelax model, see https://www.gurobi.com/documentation/8.1/refman/py_model_feasrelaxs.html#pythonmethod:Model.feasRelaxS By calling m.feasRelaxS(0, False, False, Tr...

I don't know the GLPK API, so I cannot tell you how you would load a 'mymodel.mps' into GLPK. But there should be some read function that can do this. Gurobi converts indicator constraints during p...

Unfortunately, the answer to both of your questions is "no". You can tell Gurobi to use pretty much all cuts it finds by setting the "CutPasses" parameter to a very large number. But still, Gurobi ...

You can use m.write("mymodel.mps") to save the model to disk in MPS file format. Then, you can load it into basically any solver you want, as the MPS file format is industry standard. Note that thi...