Gap does not reduce beyond a certain percentage in a MIP

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parag_patil
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Gap does not reduce beyond a certain percentage in a MIP

Post by parag_patil » 1 week ago

Dear all,

I am solving an MIP problem. It is considerably large. While the gap reduces initially, (from 375 to 14 %). Beyond this, it does not move forward.

Can you please let me know, what can I do? I have already tried many cplex parameters. But are not fruitful.
log_file_reference.txt
This is the reference log file, where the gap is stuck at a certain percentage for a long time
(40.12 KiB) Downloaded 6 times

Solver is CPLEX

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bussieck
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Re: Gap does not reduce beyond a certain percentage in a MIP

Post by bussieck » 6 days ago

MIP is a difficult (NP hard) problem class and there is no guarantee that you will be able to solve a MIP of this size to global optimality in reasonable time. You can work on the formulation etc. No easy solution.

-Michael

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