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The Master Process

 

The primary functions performed by the master process were listed in Section 3.1. If needed, the user must provide a routine to read problem-specific parameters in from the parameter file. She must also provide a subroutine for upper bounding if that is desired. A good initial upper bound can dramatically decrease the solution time by allowing more variable-fixing and earlier pruning of search tree nodes. If no upper bounding subroutine is available, then the two-phase algorithm, in which a good upper bound is found quickly in the first phase using a reduced set of variables, is recommended. See Section 5.3.2 for details. The user's only unavoidable obligation during pre-processing is to specify the list of base variables and, if desired, the list of extra variables that are to be active in the root node. Again, the selection of a good set of base variables can make a marked difference in solution speed, especially in the two-phase algorithm.



Ted Ralphs
Thu Jun 8 14:31:17 CDT 2000