
Sensitivity Analysis and Duality 327
The right-hand side of a single constraint can vary within a specified range. The
dual value of constraint will only hold while the right-hand of the constraint is in the
range of values.
A constraint that is not active has a dual value of zero. This is a constraint that is
not binding because its actual value is less (or greater) than the value of the right-hand
side specified in the problem formulation.
This second set of data is provided by computer solvers such as LP solver,
glpsol and display output results that can be used for sensitivity analysis. This
section includes discussion of the output produced by LP ...