search

Kuifje02 / vrpy

A python framework for solving the VRP and its variants with column generation.
MIT License
179 stars 43 forks source link

Compare with gurobi #129

Closed rlacjfjin closed 2 years ago

rlacjfjin commented 2 years ago

Hi, If I select gurobi solver with solver parameter, is it better than using gurobi solver directly?

Thanks

Kuifje02 commented 2 years ago

What do you mean "using gurobi solver directly" ?

rlacjfjin commented 2 years ago

I mean use gurobi solve MIP model of vrp variants with default settings. I want to know whether vrpy can accerate gurobi or better than gurobi. I remember you compare with ortools on some benchmark dataset and better than ortools, then how gap between vrpy and gurobi solver? Of course, one is open source and another is commercial, but I want to know how good vrpy is. Thanks

Kuifje02 commented 2 years ago

If you use use the option prob.solve(cspy=False), vrpy will solve the MIP model, which you can do with gurobi. You will see that as the size of the problem grows, the computation times grow exponentially. When using cpsy=True, a decomposed formulation is solved, which in theory should leed to quicker computation times. We have noticed that it is indeed the case. Feel free to play around with these options and see for your self, and get back to us if you notice anything fishy.