How do I return to single-objective mode from multi-objective optimization?

To return from multiple objectives to single-objective optimization,

• set the model attribute NumObj to 0,
• call update() on the model, and
• reset the primary objective function via setObjective().

To query the current optimization mode, use model attribute IsMultiObj.

Further information

• How do I query best bound or best objective value in multi-objective optimization?
• Feasibility relaxations of multi-objective models in Gurobi v9.0.x