Return Value

The current objective value.

The current objective value is the objective value at the point when the callback is called. In the simplex method, this objective value may not reflect the objective function defined for the model being solved, but an artificial phase 1 objective function used to achieve primal or dual feasibility. In the barrier method, where the objective functions can be computed using dual or primal vectors and both definitions are not equivalent (unless optimality is achieved), the primal objective function is returned.