Thomas Leveringhaus

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Votes on activity by Thomas Leveringhaus Recent activity Votes
  • Using CSC or CSR?

    Dear Gurobi-Team, I would like to ask whether it makes sense to think about the format in which sparse matrices are transferred to Gurobi? I assume, Gurobi will internally use any of the formats CS...

  • partition heuristic and threads

    Awaiting user input

    Dear Gurobi-Team, I set parameter Threads to value 64 so I got: CPU model: AMD EPYC 7502 32-Core Processor, instruction set [SSE2|AVX|AVX2]Thread count: 64 physical cores, 64 logical processors, us...

  • Concurrent Optimizer and callbacks


    Dear Gurobi-Team, I am using Concurrent Optimizer and callbacks and it seems to me, that callbacks are not called, although they should (or shouldn't?). In the reference manual (https://www.gurobi....

  • confusion about adding MVar.fromlist()


    Dear Gurobi-Team, I tried to use MVar.fromlist() ( but the given example does not work: import gurobipy as gpmodel = gp.Model(...

  • Place constraints back in the lazy constraint pool


    Dear Gurobi team, I would like to ask if it makes sense (or is even possible) to place constraints back in the lazy constraint pool. I understand how they are placed in the lazy constraint pool ini...

  • general discrete variables in gurobi


    Dear Gurobi-Team, is there any (direct) way to model general discrete variables in gurobi? What I mean are variables that take ("countable") specific integer or also specific non-integer values, e....

  • lazy lower bound and upper bound for Vars


    Dear Gurobi Team, I am trying to speed up the solution of an optimization problem and reduce the size of the problem. I am already using the "lazy" option for some inequality constraints of which I...

  • Hyperboloid of two sheets


    Dear Gurobi-Team, if I model the following problem, Gurobi can solve it with GRB.Param.NonConvex=-1, although the Q-constraint-matrix is non-convex (due to the positive and negative eigenvalues of ...

  • Interactions between partition heuristic and presolve


    Dear Gurubi Team, if I have two variables x1 & x2 (and others) in my model and x1 and x2 have different attributes with respect to the partition heuristic. Additionally, if I have a constraint (or ...

  • bilinear transformation and GRB.Param.NonConvex


    Dear Gurobi-Team, with my questions I refer to your following webinar: Am I right, that the bilinear transformation is only ap...