Re: [Help-glpk] Setting a constraint

2005-11-21 Thread Mihai Banciu
Hi, That constraint would make the problem nonlinear (a bunch of products of two variables). Hence, I really doubt you can do this in GLPK (where the L stands for Linear). However, the good news is that you might be able to reformulate your constraint using some simple linearization technique.

Re: [Help-glpk] Setting a constraint

2005-11-21 Thread Andrew Makhorin
Is it possible to set this constraint ? SUM (Xi * Yj) = 1 where Xi and Yj are variables in {0,1}. Your inequality can be written as follows: sum zk = 1 where zk are binary variables such that zk = xi * yj (or, equivalently, zk = xi yj). The latter constraints are still non-linear,

Re: [Help-glpk] Formulating MCKP with GNU Mathprog

2005-11-21 Thread Andrew Makhorin
I am trying to formulate a multiple choice knapsack problem. I am stuck at the point where I need to formulate subsets of a given set. From the archives of this list I have got the idea that you can it like this: set FOO; set BAR{FOO}; Am I correct here? This depends on whether

Re: [Help-glpk] GLPK and C#

2005-11-21 Thread Andrew Makhorin
I need to run my system with GLPK DLL. When I insert the GLPK DLL in the .net Project the following message is showed: This is not a valid assembly or COM component. What I need to do to run correctly the GLPK with C#.net? :/ The following messages can help: