Column Generation in Gurobi

[Andreas Wierz]

Hi, I couldn't find anything good on this topic yet.

Is it possible to do column generation using Gurobi without stopping and restarting the model over and over again?
If I try to add variables via a callback, the solver segmentation faults as soon as it leaves the callback.
I tryed adding the variables via:
GRBVar y = _mip->addVar(0.0, 1.0, 0.0, GRB_BINARY, name);
during GRB_CB_MIPSOL.

I use Gurobi 5.5.

thanks in advance,
Andreas

[Ed Rothberg]

Sorry, you can't modify the model from within a callback.

Ed

[Hugh Medal]

So if we want to do branch-and-price, would you recommend coding it from scratch? Or is there a way to utilize the Gurobi framework?

[Stuart Mitchell]

you could try DIP https://projects.coin-or.org/Dip

and its python interface DIPpy if you want, but they don't use gurobi.

STu

--

---
You received this message because you are subscribed to the Google Groups "Gurobi Optimization" group.
To unsubscribe from this group and stop receiving emails from it, send an email to gurobi+un...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

--

Stuart Mitchell

PhD Engineering Science

Extraordinary Freelance Programmer and Optimisation Guru

www.stuartmitchell.com