Pietro Belotti

Just left a note for the Xpress team.

Hi Michael,   apologies for the late reply. I agree that's too much output and I observed the same. I'm afraid the quickest way (apart from waiting for a release) is...

Hello. It would help to see how this happened; for example, which modeling language, what model you used, preceding output, etc. From the information you gave it seems that the...

Hi, indeed if the problem has binary variables then Ipopt doesn't return a feasible (integer) solution while Couenne can. Couenne uses Ipopt as a NLP solver when looking for feasible...

Thanks. The `register` keyword was removed from master and (just now) from stable/0.5. I hope to create a release/0.5.9 soon but it will take a few days.

Hi Indrajit,   The model is linear binary, so Couenne can solve it to global optimality although it is "overqualified" for this---Cbc would also find the optimum. I don't know the...

I believe the next step is to compare the .nl files produced by AMPL and by Minizinc. Maybe run Couenne by adding the option "problem_print_level 4" in the option file...

Hi Tamás,   indeed Couenne doesn't refine the solution to round off binary variables (I'm not sure if Cbc, the underlying branch-and-bound, does). so rather than floor() one should use a...

I think the couenne.opt file should be placed in the same folder where the main command is run from, i.e. not necessarily where the Couenne executable is but rather the...

Hello. In your mailing list message you mention you used amplpy. I'm not familiar with this interface but I'm wondering if you can use amplpy to produce a .nl version...