Lorenz Wagner

Hello, I have the following question. I am currently solving a Cullum generation problem and have observed the following. When I solve the subproblems, I sometimes find several optimal solutions (i...

Hi Gurobi Team,I'm implementing a column generation algorithm where, in each iteration, I solve one independent subproblem per patient (or entity) to generate new columns. Since these subproblems o...

Hello, I have the following question. I want to implement the following non-linear constraint in Gurobi. This is the constraint in question. I have linearized like this and then implemented it with...

Hello, I have the following question. I use addGenConstrExp and addGenConstrLogistic to linearly approximate an exponential and a logarithmic function. Is it possible that I can somehow output the ...

I have the following scheduling problem. Relatively simple and not very complex (only serves as an example). The indexes are \(I\) worker, \(T\) days and \(J\) shift. The decision variable is \(x_{...

Hello, I have a purely technical question about Gurobi. Suppose I have the variable \(y_{ijk} \in [0;1]\) . Now I want to define a binary variable \(x_{ijk}\)  that takes the value 1 if \(y_{ijk}=1...

Hello, I have the following problem. I am trying to evaluate the lowe bound and the incumbent via the log of my model and use the glt.get_dataframe() command to create a DataFrame. Unfortunately I ...

Hi, I came across this plot earlier and was wondering what exactly it says and how to implement it with Gurobi?I think with a callback function (as seen here), but I don't know which values I have ...

Hello, I have the following problem. I am setting up a linear programme (or so I thought), but my model output shows something like this. Model has xxxx quadratic constraints Is there any way I can...

Hello folks, I need your help. I'm currently trying to implement an old LP (which I set up as part of my research at university) in a new programming language for nostalgic reasons. The old model w...