The usage of callback

Hi all,
I have seen an example of callback usage >https://jump.dev/JuMP.jl/stable/tutorials/Optimization%20concepts/benders_lazy_constraints/ there is a line x_current = callback_value.(Ref(cb_data), x), I wonder if it should judge the integer feasibility of solutions obtainted, then adding the Benders cuts.(status = callback_node_status(cb_data, model))

See the documentation for details

https://jump.dev/JuMP.jl/stable/manual/callbacks/#Things-you-can-and-cannot-do-during-solver-independent-callbacks

Hi, odow
Thank you for your reply. I have seen the link, it uses the codes to judge the integer feasiblility during callback process. However, the Benders decomposition example doesn’t have the integer feasiblility judgement process.

Ah I misunderstood your question.

The only reason for not checking is that the tutorial was written before we added the status. Improvements to the tutorials are always welcomed if you want to make a pull request.

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Adding cutting planes without considering the integer variables constraints don’t influence the solving process?(in other words,not consider the integer variable constraints, could the Benders cuts be valid?) I thought the effect is not the same whether the integer constraints are considered.

It doesn’t matter if you add cuts at fractional solutions.

Ok,i try to test whether it is better if the integer feasibility is considered. If so, the tutorial could be improved.