[Bonmin] unexpected unfeasible problem

[Jeff Linderoth]

Hi Nicolas,

Pierre Bonami wrote:
> No, I don't have MINOS and I have no idea what the problem is.

You might try providing an initial feasible solution to the solver.
This should help for nonconvex problems, like the one you pose.

Something like...

var x0 integer >= 1 <= 10, := 1;
var y0 integer >= 1 <= 10, := 1;
var x1 >= 1 <= 10, := 5;
var y1 >= 1 <= 10, := 5;
var x2 >= 1 <= 10, := 7;
var y2 >= 1 <= 10, := 1;

> There is another MINLP solver in COIN-OR which is more aimed at global 
> optimization. Its name is LaGO. You can find it there:
> https://projects.coin-or.org/LaGO

<Shameless Plug>
And don't forget about FilMINT, which is freely available via NEOS.
http://www-neos.mcs.anl.gov/neos/solvers/minco:FilMINT/AMPL.html
</Shameless Plug>

Cheers,
-Jeff


-- 
------------------------------------------------------------
Jeff Linderoth				     O: 608-890-1931
Asst. Professor				
Industrial and Systems Engineering        linderoth at wisc.edu
University of Wisconsin-Madison