Using the barrier optimizer

Documents parameters and methods associated with the barrier optimizer.

As you have read in Introducing the barrier optimizer, the CPLEX barrier optimizer finds primal and dual solutions from the primal and dual formulations of a model, but you do not have to reformulate the problem yourself. The CPLEX barrier optimizer automatically creates the primal and dual formulations of the problem for you after you enter or read in the problem.

Specify that you want to use the barrier optimizer by setting the parameter LPMethod to one of the values in Table 1.

Table 1. Settings of LPMethod to invoke the barrier optimizer
Setting	Context
`IloCplex::Barrier`	Concert Technology for C++ users
`IloCplex.Algorithm.Barrier`	Concert Technology for Java users
`Cplex.Algorithm.Barrier`	Concert Technology for .NET users
`CPX_ALG_BARRIER`	Callable Library
`4`	Interactive Optimizer

And then you call the solution routine just as for any other CPLEX optimizer, as you see in Table 2.

Table 2. Calling the barrier optimizer
Call	Context
`cplex.solve`	Concert Technology for C++ users
`cplex.solve`	Concert Technology for Java users
`Cplex.Solve`	Concert Technology for .NET users
`CPXlpopt`	Callable Library
`optimize`	Interactive Optimizer