Silke Horn

The solver tries to apply all kinds of cuts when solving a model and chooses automatically how aggressively each kind of cut is applied. In the final overview, you only see the ones that were not d...

Hi Henrik, When using the barrier algorithm, the random seed affects mostly the ordering (and maybe the cleanup). For some models it has a bigger influence on running time than for others. I am not...

You're right. I hadn't paid attention to the objectives and iteration numbers before. Maybe the differences are due to chance? Have you tried running the same settings multiple times with different...

Hi Henrik, If you look at the logs, you can see that the barrier was a bit faster with the bigger tolerance: 424.06 seconds for 1e-7 versus 428.05 seconds for 1e-9. However, the crossover took a lo...

The error message says that you are accessing the key ('Delta', 25) which does not exist. How did you define a?

When solving the exactly same model multiple times on the same machine, the running times should be similar. Are there other processes running on the same machine at the same time that may slow do...

This looks as though you don't have write privileges in the directory where you are running your code. Best regards,Silke

Dear Tamal, I am glad this helped. You can find some more information about numerics and tolerances here: https://www.gurobi.com/documentation/8.1/refman/numerics_gurobi_guidelines.html Regards, Silke

So you are saying that you know (by some independent way) a solution to your model that is better than the solutions that Gurobi finds (and outputs as optimal)? I still don't fully understand how y...

The order of the constraints or variables may affect the solver path and hence the solution that is returned by the solver. So this is expected behavior. The solutions that are returned should, how...