Silke Horn

Hi and welcome to Gurobi! You can only use one callback function, but this function can do multiple things. (So this should not be any limitation.) Could you elaborate what you would want to do in ...

This log says that your model is infeasible (not unbounded). Does your variable x take the value 0 in the solution of the model where the lower bound for x is 0? This would then probably mean that ...

This says that you have a floating license with five tokens and all tokens are already in use by some other process.

Could you please show a complete code sample?

You can call getValue on the A[s]. E.g. for s in range(2):     print(A[s].getValue())   Note though that you first need a solution for this. I.e., you should first call optimize on your model.

Which are the expressions for which you want to get the values? Please note that you are using the variable name s twice (in the outer loop and in the loop inside quicksum) while i will be undefine...

Could you give us some more information about what exactly you are trying to do and what you need help with? Do you need help getting the values? (Both LinExpr and QuadExpr have a getValue method.)...

You are reading an attribute directly after creating the model (without e.g. optimizing first). This is one of the very rare situations where you have to call model.update() first. Here is more inf...

Yes, you can create arbitrary LinExpr objects from your model's variables and -- once the model is solved -- access the expression's value with the getValue-method.

I assume you have multiple versions of Gurobi (and hence grbgetkey) installed. Either remove the old version or make sure the latest one comes first in your PATH. The command "which grbgetkey" shou...