# How to implement a local search with different operators?

Operations Research Asked on September 1, 2020

I read some papers on local search. I remark that several authors use different move operators. However, the pseudo-code I found on google only uses one operator.

I am wondering how to implement the local search algorithm using different operators. Do I need to run them at the same time or successively? how? Could someone point me to a pseudo-code for the case of several operators?

Edit: I heard some bad things about the algorithm suggested in the answer VNS. What do you think of? Is it the only way to manage different operators?

I suggest you take a look at Variable Neighborhood Search (VNS) method. The Wikipedia page has some useful pseudo codes.

My answer to OP EDIT: First, I think there is no good or bad algorithm, it depends on how you use the different features.

Getting back to your question, of course VNS is not the only way to have multiple operators. You can implement multiple operators in many meta-heuristics, e.g., in an Iterated Local Search, Simulated Annealing, Tabu Search, etc. One way to do so is to define a probability for each operator, and each time you pick the operator based on the probability.

Answered by Mostafa on September 1, 2020

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