Eli Towle

Hi Robert, Assuming your decision variables were added in the following manner: A = m.addVars(range(1,4), range(1,3), name="A") you can print a line for each row as follows: for i in range(1, 4):  ...

Hi Robert, Assuming you want to look for variables whose names start with these letters, you can use the following: for v in m.getVars():    if v.varName.startswith("AA"):        print("AA")    eli...

Hi Xinyue, You can use the X attribute to retrieve a variable's value in the current solution. E.g., for t in range(1,25):    print(DESS[t].X)    print(CESS[t].X) I hope this helps!

Hi Cedric, Thanks for reporting this issue. This has been fixed in Gurobi 9.0, scheduled for release this fall. Eli

Hi Cedric, I suspect the issue is caused by this conditional statement: if E_VAR[e].getAttr(GRB.Attr.X)==1: For numerical reasons, Gurobi uses a tolerance to determine whether or not a variable is ...

Hi Robert, Yes, those two expressions are equivalent (though the terms may be ordered differently within the LinExpr objects). Eli

Hi Shunji, Presolve assumes that a model is feasible and bounded. Because this model is infeasible, some presolve reductions can have unexpected behavior that results in constraint violations. For ...

Hi Robert, It looks like you're adding a constraint that fixes a set of variables to constant values. It's a better idea to simply add the fixed values directly to the model wherever those variable...

Hi Abbas, Greg suggested the PreCrush parameter as an alternative to the Presolve parameter for your situation. In either case, if you also want to disable cuts and heuristics, you still need to se...

Hi Bradley, Can you clarify what you are trying to do? It sounds like you want to add a constraint that T[i][j] is equal to one of two values: either T[i][j], or T[i][k]*T[k][j]. If this is your in...