I have a MIP in the file, untitled.lp that is attached. I have used 'lp2poly' to load the problem into Polymake. This MIP has both 0/1 binary variables, as well as continuous variables with their respective ranges. I'm not sure why I'm getting warnings in finding the MINIMAL_SOLUTION of this problem. I think It should be straight forward. For verification, I have checked the properties: the problem is Unbounded, Feasible and Pointed.

The Polymake script used is as follows:

Code: Select all

```
polytope > $x = lp2poly("Downloads/untitled.lp");
polytope > $obj= new Vector([1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1]);
polytope > $milp = $x->MILP(LINEAR_OBJECTIVE=>$obj);
polytope > print $milp->MINIMAL_SOLUTION;
polymake: WARNING: could not compute 'MINIMAL_SOLUTION' probably because of unsatisfied preconditions:
precondition : POINTED ( BOUNDED: ) ( applied to parent )
precondition : BOUNDED ( to.milp: MILP.MINIMAL_VALUE, MILP.MINIMAL_SOLUTION : MILP.LINEAR_OBJECTIVE, FACETS | INEQUALITIES ) ( applied to parent )
precondition : FEASIBLE ( FACETS, AFFINE_HULL, CONE_DIM : CONE_AMBIENT_DIM ) ( applied to parent )
precondition : FEASIBLE ( VERTICES, LINEALITY_SPACE, CONE_DIM : CONE_AMBIENT_DIM ) ( applied to parent )
polytope > print $x->POINTED;
true
polytope > print $x->BOUNDED;
false
polytope > print $x->FEASIBLE;
true
```

I tried solving it as LP by removing the "GENERAL x#13 x#31 ....." conditions in the attached 'untitled.lp'. I was able to get the MINIMAL_VALUE = 7 but how can I find all the minimal feasible solutions/computation time reports etc.?

Code: Select all

```
polytope > $lp = $x->LP(LINEAR_OBJECTIVE=>$obj);
polytope > print $lp->MINIMAL_SOLUTION;
polymake: ERROR: Can't locate object method "MINIMAL_SOLUTION" via package "Polymake::polytope::LinearProgram__Rational"
polytope > print $lp->MINIMAL_VALUE;
7
```

Thanks for your time in advance!