[Help-glpk] generalized branching with IOS

[Rafael Ávila de Espíndola]

I have a particular problem (register coloring) that I am trying to solve with 
a branch-and-price algorithm. Each column is an independent set.

I was looking at the IOS API and the column generation part is simple. The 
problem is that it is very inconvenient to branch in one of the variables. It 
would mean to fix a independent set an being present or not in the final 
solution. The branches are very unbalanced and, in the case a column is fixed 
in 0, it is hard to make sure that another identical column will not be 
generated.

Has someone already used a generalized branch with IOS? What do you think 
about a 
void ios_generazed_branch(IOS *ios, int ne, double *v, double rhs, int next);

that would add the row ( v <= rhs) to one branch and the row (v >= rhs + 1) to 
the other?
 
Thanks,
Rafael

pgp9lSo1Yogpj.pgp
Description: PGP signature