Solving a single continuous model

Shows how to choose the optimizer to solve a single continuous model.

To choose the optimizer to solve a single continuous model, or the first continuous relaxation in a series, use

IloCplex.setParam(IloCplex.IntParam.RootAlg, alg)

where alg is an integer specifying the algorithm type. Table 1 shows you the available types of algorithms.
Table 1. Algorithm types for RootAlg
alg Algorithm Type LP? QP? QCP?
0 IloCplex.Algorithm.Auto yes yes yes
1 IloCplex.Algorithm.Primal yes yes not available
2 IloCplex.Algorithm.Dual yes yes not available
3 IloCplex.Algorithm.Network yes yes not available
4 IloCplex.Algorithm.Barrier yes yes yes
5 IloCplex.Algorithm.Sifting yes not available not available
6 IloCplex.Algorithm.Concurrent yes yes not available

You are not obliged to set this parameter. In fact, if you do not explicitly call IloCplex.setParam(IloCplex.IntParam.RootAlg, alg), CPLEX will use the default: IloCplex.Algorithm.Auto. In contrast, any invalid setting, such as a value other than those of the enumeration, will produce an error message.

The IloCplex.Algorithm.Sifting algorithm is not available for QP. IloCplex will default to the IloCplex.Algorithm.Auto setting when the parameter IloCplex.IntParam.RootAlg is set to IloCplex.Algorithm.Sifting for a QP.

Only the settings IloCplex.Algorithm.Auto and IloCplex.Algorithm.Barrier are available for a QCP.