Matthias Miltenberger
Gurobi StaffGurobi Optimization Support Manager  Berlin, Germany
 Total activity 1040
 Last activity
 Member since
 Following 0 users
 Followed by 0 users
 Votes 43
 Subscriptions 443
Activity overview
Latest activity by Matthias Miltenberger
Matthias Miltenberger commented,
Hi Sanket, The only way I can think of to incorporate the results from tools like Porta or Polymake into Gurobi is via callbacks. But I don't think this is going to help you much because you only h...

Matthias Miltenberger commented,
I don't have much to add to Jonasz' comment. His suggested tools are way more specialized for this purpose and should be much easier to use to solve that problem. Cheers,Matthias

Matthias Miltenberger commented,
Hi Kamal, Exactly, nonbasic constraints are binding or active. Their associated slack variable is 0. Cheers,Matthias

Matthias Miltenberger commented,
Hi Vanny! I could not spot an obvious error in your formulation, except that you are using indicator constraints in (5), (7), and (8). I would also put the upper bounds on your capacity variables r...

Matthias Miltenberger commented,
Hi Carol! It's not clear to me what the relationship is between the binary Service variable and the X and Y variables. Is there just a single Service variable? Maybe this article can help you model...

Matthias Miltenberger commented,
That is interesting! Can you try updating your Gurobi version to 10.0.2? And can you also try running this on a different machine, if possible? Thanks,Matthias

Matthias Miltenberger commented,
That is very hard to say upfront. It also depends on your model and whether the reformulation still makes sense and provides a meaningful solution. Cheers,Matthias

Matthias Miltenberger commented,
Yes, linear constraints and objectives are almost always easier to optimize than quadratic or general nonlinear ones. Cheers,Matthias

Matthias Miltenberger commented,
Hi! This is a pretty huge model with lots of nonlinearities (6 million general constraints, 1.4 million quadratic objective terms). It very much looks like you are running out of memory here. You s...

Matthias Miltenberger commented,
Hi Helen, All variables in Gurobi have an implicit lower bound of 0  it is customary to model with nonnegative variables. I imagine that the infeasibility comes from your continuous deviation vari...