acceptable_obj_change_tol:

"Acceptance" stopping criterion based on objective function change. $\;$
If the relative change of the objective function (scaled by Max(1,|f(x)|)) is less than this value, this part of the acceptable tolerance termination is satisfied; see also acceptable_tol. This is useful for the quasi-Newton option, which has trouble to bring down the dual infeasibility. The valid range for this real option is $0 \le {\tt acceptable\_obj\_change\_tol } < {\tt +inf}$ and its default value is $1 \cdot 10^{+20}$.