[Coin-bcpdiscuss] Information on the children of a node

[fmargot at andrew.cmu.edu]

Sumitra:

One way to do this is to use BCP_user_data. When the sons are created,
put a flag in a BCP_user_data object to identify which is which. This
is described in bac.pdf (although not for column generation) 
that you can find in the subdirectory Bcp/examples/BAC of your
installation directory.

Francois


On Sun, 28 Jan 2007, Soumitra Pal wrote:

> Hi,
>
> I am trying to implement the branching strategy used by "P.H. Vance. 
> Branch-and-Price Algorithms for the One-Dimensional Cutting Stock Problem, 
> Computational Optimization and Applications, 9(3):211?228, 1998." for solving 
> the cutting stock problem. The problem is solved using column generation.
>
> According to the strategy, on one branch the solver to the subproblem should 
> not generate one particular pattern (or column). So, I need to identify the 
> node in the BCP_user_lp::initialize_new_search_tree_node() function. This 
> should be easy if I could store the indices of the two children created in 
> the BCP_user_lp::set_actions_for_children() function and check the index in 
> the initialize_new_search_tree_node() function. However, I cant see how to do 
> this. It will be great if somebody explains this.
>
> Also, I will be thankful if you explain me the term "phase" as returned by 
> the function current_phase() in the BCP parlance.
>
> Thanks in advance,
> Soumitra.
>
>
>