is there an optimization package which performs mixed integer programming (constrained) optimization for linear or quadratic objective / constraint functions problems ?
I have found out that GENO 2.0 does it. Is there some other package not using genetic algo to perform mixed integer programming (constrained) optimization?
There isn't one written in GAUSS. I've used GENO and I find it to be quite powerful. There's a slight learning curve, not as easy to use as some other GAUSS Applications, but well worth it in my opinion. Also, the advantageous feature of genetic algorithms is that they look for global solutions.
GENO also handles multiple objectives.