Re: [Help-glpk] Callbacks for column generation

2009-12-09 Thread Andrew Makhorin
What would happen if i add cols in a callback when the reason for calling the calback is GLP_IROWGEN, it would start adding columns to the global problem?. To represent subproblems, i.e. nodes of the search tree, the glpk mip solver uses the original problem object (glp_prob) passed to it from

Re: [Help-glpk] Callbacks for column generation

2009-12-09 Thread Javier Zambrano
Thanks, another question, can you get the final branch and bound tree after the mip is solved?, i could add columns in each node and then add to the initial relaxation and re-optimize. Regards Javier 2009/12/9 Andrew Makhorin m...@gnu.org What would happen if i add cols in a callback when

Re: [Help-glpk] Callbacks for column generation

2009-12-09 Thread Andrew Makhorin
Thanks, another question, can you get the final branch and bound tree after the mip is solved?, i could add columns in each node and then add to the initial relaxation and re-optimize. The glpk mip solver does not keep fathomed nodes, so if the mip is solved (to optimality), the final tree is