Thomas Leveringhaus

Thank you David!

Hi David, thank you for your answer: Then it is a feature not a bug ;-) But that is a pity for me, because I can't save the new found solution to file during optimization. Is there a special reaso...

Or maybe Callbacks are called from alle ConcurrentMIP-Instances but maybe identifying "if where == GRB.Callback.MIPSOL" doesn't work properly in different instances?

Hi David, I have a callback-function like this (in python): def writesolution_callback(model, where):    if where == GRB.Callback.MIPSOL: [...] # processing of the solution and creation of t...

Hi David, I redeveloped/improved my optimization modell. In the past I saw improvements with the heuristic, but actually gurobi does not even start the heuristic although I set PartitionPlace to 31...

Thanks, that works :-)

Hi Jaromil, thanks for your answer. Maybe that already answers my question, but I am not totally sure. I think of three statuses, a constraint can have: active, inactive & lazy. If a constraint sta...

Hi Riley, addGenContrPow is an interesting option. I knew it existed, but it didn't come to my mind to use it for my specific problem ... As far as I know, Gurobi internaly uses some kind of piecew...

Hi Riley, thank you very much for your answer - your suggestion is an interesting "modeling trick" to me. It also gave me another idea to reduce the number of constraints. What do you think about t...

Hi Jaromił, I see the obvious tradeoff between reducing the model size and not getting information from lazy bounds or constraints. FYI:I have huge sets of constraints to prevent islanding in an Op...