GRBgetmultiobjenv

GRBenv* GRBgetmultiobjenv ( GRBmodel *model,
    int num )

Create/retrieve a multi-objective environment for the optimization pass with the given index. This environment enables fine-grained control over the multi-objective optimization process. Specifically, by changing parameters on this environment, you modify the behavior of the optimization that occurs during the corresponding pass of the multi-objective optimization.

Each multi-objective environment starts with a copy of the current model environment.

Please refer to the discussion of Multiple Objectives for information on how to specify multiple objective functions and control the trade-off between them.

Please refer to the discussion on Combining Blended and Hierarchical Objectives for information on the optimization passes to solve multi-objective models.

Return value:

The environment associated with a given optimization pass when solving the multiobjective model. A NULL return value indicates that there was a problem retrieving the environment.

Arguments:

model: The model from where we want to retrieve the multiobjective environment.

num: The optimization pass number, starting from 0.

Example usage:

  GRBenv *env0 = GRBgetmultiobjenv(model,0);
  GRBenv *env1 = GRBgetmultiobjenv(model,1);

  GRBsetintparam(env0, "Method", 2);
  GRBsetintparam(env1, "Method", 1);

  GRBoptimize(model);

  GRBdiscardmultiobjenvs(model);