The routineCPXqpopt may be used, at any time after a continuous quadratic program has been created, to find a solution to that problem using one of the CPLEX quadratic optimizers. The parameter CPX_PARAM_QPMETHOD controls the choice of optimizer (Dual Simplex, Primal Simplex, or Barrier). With the default setting of this parameter (that is, Automatic) CPLEX invokes the barrier method because it is fastest on a wide range of problems.

Example

 status = CPXqpopt (env, lp);

The routine returns zero unless an error occurred during the optimization. Examples of errors include exhausting available memory (CPXERR_NO_MEMORY) or encountering invalid data in the CPLEX problem object (CPXERR_NO_PROBLEM). Exceeding a user-specified CPLEX limit, or proving the model infeasible or unbounded are not considered errors. Note that a zero return value does not necessarily mean that a solution exists. Use the query routines CPXsolninfo, CPXgetstat, and CPXsolution to obtain further information about the status of the optimization.