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Hello,

I found an example script which imports a .vrp format file and returns the optimal routing result in this repo.

I want to know how can I write the .vrp file as I want. That is, I want to specify customer nodes positions and so on. Actually, I have opened the .vrp file with a text editor, and I don't understand the syntax.

When I google it with some keywords like vrp file expansions syntax but I cannot reach what I want.

Thank you in advance!

VeRyPy has a proven implementation of 3-opt* that operates on the entire solutions (which resides in local_search/solution_operators.py. Proven here means that it is able to replicate results from the literature.

3-opt* was one of the trickiest heuristics to implement, and, hence, there were many attempts, some of which remain incomplete. These were left where they were, because, even if the 3-opt* solution operation is verified to work through replication of Stewart & Golden results, VeRyPy would benefit from supporting implementations. For example, the 2 and 3 route heuristics as incompletely implemented in the do_3optstar_2route_move and do_3optstar_3route_move would allow a more convenient use of the 3-opt* in some special occasions. Another advantage would a unified interface to 3-opt* although with a slight performance and maintenance penalty.

While you, good reader, are at it, please also consider writing the do_naive_3optstar_move. In fact, thinking about it, that would be perfect place to start!

One can get many ideas from the excellent presentation of Victor Pillac: https://victorpillac.wordpress.com/2013/05/22/vrp-2013-computational-aspects-of-vehicle-routing/

Every slide there has great gems.

I am not able to add a charging constant for the ECVRP problem. Is there any way to add a charging stations and charging constant for the ECVRP problem

I have started doing this and should upload them to a branch someday.

https://pythonhosted.org/sphinxcontrib-restbuilder/

There should be a simple GUI for solving problems in .tsp .vrp or .csv (a list of coordinates or addresses) format. The easiest way is probably PySimpleGUI and some nice theme e.g. https://github.com/rdbende/Sun-Valley-ttk-theme

It is a great work but I wonder that can we use coordinate map distance from google api in order to get the real distance or not?

I want to generate all the Routes for a school with the following given data:-

• Capacity of the busses
• Location [lat,lng] of the school
• Location [lat,lng] of all the stops.

I need to generate the most optimal routes based on the stops, so was thinking of applying heuristics for the solution (Gillet & Miller Sweep heuristic).
All [Lat, Lng] data are available.

• Blue Marker in the map is the school Location
• Yellow Markers are the Stops

?

How can I use the VeRyPy for this ?

Is the description correct https://github.com/yorak/VeRyPy/blob/master/local_search/inter_route_operators.py#L301? Do you mean differentiate from inter-route one or intra-route one?

This is a really wonderful collection of heuristics for CVRPs -- great job!

I'm wondering whether there are any algorithms here that are applicable for VRPs with time windows. Alternatively, do you have any good pointers to descriptions / implementations of heuristics for VRPTWs?

Thanks!
~ Ben

Hi ,
I am pretty new to vrp problems. Is there documention of this project to understand it better?

This would make it considerably easier to start using VeRyPy.

For example, for a solution [0, 1, 2, 3, 0, 4, 5, 6, 7, 0] the corresponding endnode_to_route values would be [X, 0, None, 0, X, 1, None, None, 1, X]. Currenlty, the depot is assigned to the route 0 in endnode_to_route, but with a cursory glance, it would probably also be assigned to None (to indicate this, I've used X in the example), which would make the use of None in the code more consistent.

Hi, I have tried to run your code for the vrptw and its is working perfectly for the arp, but I have an issue when timewondows are applied,
The following line is causing the issue: "wait_times = [max(0, ctrs['TWs'][i][TW.OPEN]-D[0,i]) for i in range(0,N)]".
Python gives me an error that "'int' object is not subscriptable", which I found out lies in the ctrs['TWs'][i][TW.OPEN] part of it.

Do you also have this issue or does it work with you?

Thank you so much on beforehand.

Regards
Line

The test code was written first. Revise the names in the https://github.com/yorak/VeRyPy/tree/master/tests/replication_tests.