You can provide a known solution (for example, from a MIP problem previously solved or from your knowledge of the problem) to serve as the first integer solution. When you provide such a starting solution, you may invoke relaxation induced neighborhood search (its RINS heuristic) or solution polishing to improve the given solution. This first integer solution may include continuous and discrete variables of various types, such as semi-continuous variables or those in lazy constraints, linearized constraints, or special ordered sets.

You can establish MIP starting values by using the method setVectors in a Concert Technology application, or by using CPXcopymipstart in a Callable Library application.

For Interactive Optimizer use, or as an alternative approach in a Concert Technology or Callable Library application, you can establish MIP starting values from a file. MST format (described briefly in the reference manual ILOG CPLEX File Formats) is used for this purpose. Use the routine CPXreadcopymipstart in the Callable Library, the method readMIPStart in Concert Technology, or the read command in the Interactive Optimizer, for this purpose.

At the end of a MIP optimization call, when a feasible (not necessarily optimal) solution is still in memory, you can create an MST file from the Callable Library with the routine CPXmstwrite, from Concert Technology with the method writeMIPStart, or from the Interactive Optimizer with the write command, for later use as starting values to another MIP problem. Care should be taken to make sure that the naming convention for the variables is consistent between models when this approach is used.