Objective gives the objective function for the original nonlinear program. Viol gives the maximum violation of the nonlinear constraints. RG is the reduced gradient for the linearized subproblem. NSB is the number of superbasics. If there appears to be difficulty, such as unbounded subproblems, the penalty parameter will be increased.
Step is the step size taken towards the solution suggested by the last major iteration.
Ideally this should be 1.0, especially near an optimum. It may be more meaningful if the solution vector x is very large. For an optimal solution, these numbers must be small.