[BCP] Fwd: BCP_vg_user not instantiated, generate_vars never being called

[Dani]

Hi all,

I'm trying to get working a very little column generation example (3
variables and constraints). I use the BCP_vg_user class (generate_vars,...)
instead of using those methods from BCP_lp_users (generate_vars_in_lp,...).
As I try to use that class (my own subclass of BCP_vg_user), my code breaks
because generate_vars is never called.

The odd part of the problem is that USER_initialize::vg_init (my subclass)
is never being called neither (and therefore it's kind of normal that
generate_vars never gets called). I've been tracing Bcp's code but I didn't
find why.

In the following debug excerpt , you can see that my lp_init and tm_init
methods are called (in bold) but not the vg_init nor generate_vars (lines
starting with :::::: have been added by me):

BCP_parameters::read_from_stream   Scanning parameter stream.
BCP_parameters::read_from_stream   Scanning parameter stream.
BCP_parameters::read_from_stream   Scanning parameter stream.
BCP_parameters::read_from_stream   Scanning parameter stream.*
:::::: Creating TreeManager*
:::::: TreeManager::initialize_core done
:::::: TreeManager::create_root done
*:::::: Creating LinearProgramSolver
* LP: Default unpack_module_data() executed.
:::::: LinearProgramSolver::getOsiSolverInterface done
##########################################################
TM: Starting phase 0
##########################################################
:::::: TreeManager::init_new_phase

LP: **** Processing NODE 0 on LEVEL 0 (from TM) ****
 LP: Default initialize_new_search_tree_node() executed.
 LP: Default purge_slack_pool() executed.

LP: *** Starting iteration 1 ***
 LP: Default prepare_for_optimization() executed.
Clp0000I Optimal - objective value 0
LP:   Matrix size: 3 vars x 3 cuts
LP:   Solution value: 0.0000 / 2 , 0
 LP: Default display_lp_solution() executed.
  LP : Displaying LP solution (RelaxedSolution) :
  LP : Displaying solution :
 LP: Default test_feasibility() executed.
 LP: Default test_full() executed.
 LP: Default pack_feasible_solution() executed.
 TM: Default unpack_feasible_solution() executed.
TM: Solution found at 0.001 sec.
TM: Solution value: 0.000000 (best solution value so far: infinity)
 LP: Default logical_fixing() executed.
LP:   Row effectiveness: rownum: 3 ineffective: 3
LP:   Number of leftover cuts: 0
 LP: Default generate_cuts_in_lp() executed.
LP:   Number of cuts received from CG: 0
LP:   Total number of cuts in local pool: 0
LP:   Number of leftover vars: 0
 LP: Default generate_vars_in_lp() executed.
LP:   Number of vars received from VG: 0
LP:   Total number of vars in local pool: 0
 LP: Default generate_heuristic_solution() executed.
LP:   In iteration 1 BCP generated 0 cuts and 0 vars before calling branch()
 LP: Default display_lp_solution() executed.
  LP : Displaying LP solution (FinalRelaxedSolution) :
  LP : Displaying solution :
 LP: Default select_branching_candidates() executed.
 LP : No var/cut in pool but couldn't select branching object.


Thanks in advance. An example using BCP_vg_user will do the trick too :-D
(if I get mine's working I would be glad to contribute it to COIN-OR).

Dani.

PS: I can show the code and the makefile on demand basis... it's too
cumbersome to post it here .  I'm using Bcp 1.1.3 <http://1.1.3.>




-- 
Dani.
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