Different solvers use different definitions. Here are some examples of how a definition of the relative gap can look like:
abs(bestpossible - bestfound) / abs(bestpossible) abs(bestpossible - bestfound) / (abs(bestfound) + epsilon) No matter what: 0% means optimal ---------------------------------------------------------------- Erwin Kalvelagen Amsterdam Optimization Modeling Group [email protected] http://amsterdamoptimization.com ---------------------------------------------------------------- On Thu, Dec 3, 2015 at 12:10 AM, usa usa <[email protected]> wrote: > Hi, > > I would like to find the theoretic formula about the integrality gap for > > 1. Mixed integer linear programing model and its linear programming > relaxation > 2. 0-1 knapsack integer programing model and its linear programming > relaxation > > Sometimes the gao may be called relative error or approximation ratio. > > I would like to see the formula that express the gap mathematically. > > Any help would be appreciated. > > Best Regards, > > David > > _______________________________________________ > Help-glpk mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/help-glpk > >
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