Explain more about this code please.

[maryam2171]

Hello N-Wouda
This is the first time that I want to solve a model with metaheuristics. I want to use ALNS for my VRP-TW model. Could you explain how should I use these files and which file should be changed and adapted with my model?
Thank you.

[N-Wouda]

Hi @maryam2171,

You might want to look at #50 for more discussion about time windows. I do not have any ready-made code for the VRP with time windows, however. You can also have a look at the TSP example here for how to use the ALNS package.

[maryam2171]

Thank you for responding and suggesting the TSP example.
So what is the application of this code? I mean in what cases we can use it?
Sorry, I'm a beginner with this website and this is my first experience.

[N-Wouda]

@maryam2171 I'm not sure what you're asking 😅. The purpose of the TSP example is to solve an instance of TSP using the ALNS package. You can use it to solve that problem, or other TSPs like it.

It is relevant to your situation because VRP generalises TSP to multiple vehicles, and then VRPTW generalises that to include time windows. You might thus be able to adapt the operators of the example to your situation. You could further have a look here for an ALNS heuristic that solves a different VRP variant.

[maryam2171]

@N-Wouda yes ,TSP is ok. So If I want to solve electric VRP-TW with ALNS you suggest to focus on https://github.com/N-Wouda/OR-Analysis/tree/master/heuristic ? Thank you

[N-Wouda]

@maryam2171 maybe, if you are ready to implement things. Do you have a list of operators you want to include in your ALNS heuristic? Do you know why you want those operators, and not others? Have you written that out in some detail on paper? To ease your life a little, you should probably base some of your operators on existing ALNS heuristics for the (electric) VRPTW from the literature. Have you looked for relevant papers?

If your answer to all that is 'yes', you should be ready to start implementing the heuristic. At that point, the OR-Analysis repository I linked might be helpful. But it begins with a good plan! :-)

[maryam2171]

@N-Wouda yes, I've read some of them but not exactly. thanks for your help. I hope the OR-Analysis would be useful.

[N-Wouda]

@maryam2171 I'm closing this issue because I have not heard from you for some time. If you have something new to discuss, feel free to let me know by opening a new issue. Have a great day!