The routine CPXdualopt may be used at any time after a linear program has been created via a call to CPXcreateprob to find a solution to that problem using the dual simplex algorithm. When this function is called, the CPLEX dual simplex optimization routines attempt to optimize the specified problem. The results of the optimization are recorded in the CPLEX problem object.

Example

 status = CPXdualopt (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 is not considered an error. Proving the model infeasible or unbounded is not considered an error.

Note that a zero return value does not necessarily mean that a solution exists. Use query routines CPXsolninfo, CPXgetstat, and CPXsolution to obtain further information about the status of the optimization.