[SCIP] Deactive constraint in a substree

[Ambros Gleixner]

Dear Xu Liding,

Sorry for the wait.  SCIPdelConsLocal() is your friend:

https://scipopt.org/doc/html/group__LocalSubproblemMethods.php#gaf6738f851626c9248b8e3786ee45f842

It disables a constraint at the *current* node, so you need to call it 
when SCIP enters the "y=1" child node.  If you do not already have a 
plugin with the right timing, you could, e.g., write an event handler 
that catches SCIP_EVENTTYPE_NODEFOCUSED.

Hope that helps,
Ambros



Am 24.08.20 um 14:09 schrieb liding xu:
> Dear all,
>     As I defined a branch rule on a binary variable of which a 
> constraint becomes feasible in in the upbranch, can I declare this 
> constraint to be inactive at the branch node?
>      For example, constraint: sum_{i=1}^{n} x_i  / n <= y,  x_i \in 
> {0,1}, y in {0,1}, when I branch on y, and in the branch y =1, this 
> constraint is useless,
> 
> Best regards,
> XU Liding
> 
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-- 
Ambros Gleixner, Research Group Mathematical Optimization Methods at 
Zuse Institute Berlin, http://www.zib.de/gleixner