Maliheh Aramon

Hi Tobias,  To model a fractional expression like \(\frac{x}{y}\) with \(x\) and \(y\) being quadratic and linear expression, respectively, you need to define an auxiliary variable \(z\) where \(z ...

Hi James,  Let us define the set \(S\), \(S = \{(s_i, s_j) | s_i ~\mbox{and} ~s_j ~ \mbox{are consecutive shifts}\}\), containing tuples of consecutive shifts. Given \(x_{ws}\) is a binary decision...

Hi Anjula, Yes, this is a common issue for the QCP models with challenging numerics. Scaling your model manually, if possible, to ensure the model numerics look reasonable is the best approach to a...

Hi Benjamin, You might find the documentation of the Cluster REST API useful. If you are using the Gurobi Cluster Manager, the complete documentation on REST API can be accessed at Help -> REST API...

Hi Alexander,  To warm start an LP in the Gurobi Optimizer using a start vector, you need to set both PStart for every variable and DStart for every constraint. I can think of two alternatives that...

Hi Ahmed,  Yes, if the quadratic expressions include at least one binary variable, the Gurobi Optimizer can be directed to state these expressions in different ways controlled by the parameter PreQ...

Hi Tanmoy,  Do you mean your model formulation is parametrized based on a given \(p\) value? Gurobi Callbacks provide some flexibility such that you can add new lazy constraints to the model by the...

Hi Wei, I just tested this by running the example problem \(\texttt{mip1.m}\) in MATLAB R2021b on macOS and I was able to save the log file. I explicitly set the \(\texttt{params.logfile}\). Do you...

Hi Kim, Your code is a bit complicated and I cannot read through it easily. As far as I understand, you are trying to implement the following mathematical model: Notation \(G = (V, E)\): A graph ...

Hi Jochem, One possible idea to debug this behaviour is to solve the first model with the optimal solution of the second model. Given your explanation, the first model should result in infeasibilit...