[SCIP] checking gaplimit before branching

[Horváth Markó]

Dear all,

I'm using SCIP-3.2.0 and I'm dealing with a branch-and-cut procedure, 
and I set gaplimit to 0.005 (that is, "limits/gap" was set to 0.005). 
Here is my output:

/> (...)/
/> 35.0    1  38r    663    663    6913.000      -- 6924.000    Inf//
//> (pricing) no new column(s)//
//> (general event handler) [lpsolved] LP of node 1 was completely 
solved with cut & price//
//> (branching) branching at node 1//
//> (branching) branching node: 1 same node: 2 diff node: 3//
//> (general event handler) [nodebranched] the focus node 1 has been 
solved by branching//
//> problem has been solved with gap 0.0016/
/> (...)
/
In this output you can see that after some iterations my pricer could 
not find new columns (hence my pricer sets result to RESULT_SUCCESS), 
and SCIP says that the LP of node 1 was completely solved with cut & price/.
/So the root lowerbound is equal to 6913.000 and we also have a primal 
solution with value 6924.000. So we have reached the gaplimit at the 
root node, but as you can see SCIP didn't terminate but performed a 
branching (actually using my branching rule). It's not a big deal, but I 
wonder if we could avoid this unnecessary step (i.e., we could check gap 
limit after a node is solved with cut & price).

Best regards,
Marko

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