> I use " glp_ios_branch_upon(glp_tree *tree, int j, int sel) " to > select a next variable to branch on. > Here I set int sel = GLP_NO_BRNCH which says that it uses general > selection technique. > > Can you please tell when it uses general selection technique, does it > use a heuristic suggested by Tomlin > to select next branch based on pseudo-costs or anything else?
If you call glp_ios_branch_upon, the mip solver branches on the variable chosen by you, so in this case the branching heuristic specified by the br_tech control parameter is *not* used. > > Also, if for any other method of variable selection which I implement, > how can I use same technique to select next branch? > Do I need to copy the subroutine branch_drtom to my code and then say > int sel = GLP_NO_BRNCH wherever it says > select up or down branch to branch on? > In principle, yes. Note, however, that Driebeck-Tomlin's heuristic includes not only choosing a branching variable, but also choosing the branch to be solved next. _______________________________________________ Help-glpk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-glpk
