First of all I would just like to say hello too you all and I hope I wont make a complete fool out of myself for writing this :)
I am trying to solve a train dispatching problem. I have a graph with 54 nodes and I want two trains to travel from different starting nodes and switch places. So basically I want train a to go from node i to node j and I want train b to go from node j to node i. I have set up a simple mathematical model to avoid collisions between the trains. The error message I get from running this is the following: spx_invert: the basis matrix is singular spx_simplex: numerical problems with basis matrix spx_simplex: sorry, basis recovery not implemented yet mip_driver: cannot solve current LP relaxation lpx_integer: cannot solve current LP relaxation Now this is a fairly big problem and I am not sure glpk can solve it at all. So I am mostly trying to understand _why_ it cant solve it. My guess is that it just is to big, but I wanted to make sure that that is the case and I hope maybe one of you could confirm it or explain it to me. If you want the acctual data and model files just say so and I will supply them. Best regards /Olle Claeson _______________________________________________ Help-glpk mailing list Help-glpk@gnu.org http://lists.gnu.org/mailman/listinfo/help-glpk
