You specify the bounds or ranges that FeasOpt may consider for modification by assigning positive preferences for each. A negative or zero preference means that the associated bound or range is not to be modified. One way to construct a weighted penalty function from these preferences is like this: where vi is the violation and pi is the preference.

Thus, the larger the preference, the more likely it will be that a given bound or range will be modified. However, it is not necessary to specify a unique preference for each bound or range. In fact, it is conventional to use only the values 0 (zero) and 1 (one) except when your knowledge of the problem suggests assigning explicit preferences.