|Subject:||Re: [Help-glpk] Branch and cut tree representation.|
|Date:||Wed, 24 Feb 2010 14:26:55 +0100|
Hi Mr. Makhorin,i'm just thinking which i can comment this code line which call the function :ios_delete_node(tree, p);in this point:fath: /* the current subproblem has been fathomed */if (tree->parm->msg_lev >= GLP_MSG_DBG)xprintf("Node %d fathomed\n", p);/* freeze the current subproblem */ios_freeze_node(tree);/* and prune the corresponding branch of the tree */ios_delete_node(tree, p); <------###########/* if a new integer feasible solution has just been found, otherbranches may become hopeless and therefore should be pruned */if (mip->mip_stat == GLP_FEAS) cleanup_the_tree(tree);if i do that there are side effects or it is the right way?Excuse me for my ignorance but i really don't understand by reading the reference how and which parameteri can give to the callback function, could you give an example?Kind Regards,IG2010/2/24 Andrew Makhorin <address@hidden>> Well, there is any way to obtain the entire list of nodes and build
> the tree?
Currently such a feature is not supported.
> Is possible to modify the B C api #39;s to obtain that list?
In principle, yes. You can trace each new node of the tree in the
the callback routine specifying it in the parameter list passed to
glp_intopt. For more details please see the glpk reference manual
included in the distribution.
Another way is to patch the glpk source code (see the routine
ios_driver in file src/glpios03.c). See also the BAK package
developed by Brady Hunsaker, which allows visualizing the search
tree for three mip solvers including glpk:
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