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My problem does not start with a construction. It starts with a Boolean function which I convert to a set of linear inequalities and then input those inequalities as a H-representation of a convex hull to Sage, then convert it to its V-representation to make sure that the set of linear inequalities I generate is correct. Please let me know if this is clear enough. Thanks

Hi,

If I have an array of inequalities (ieqs) that I define as a polyhedron through the command p = Polyhedron(ieqs = ieqs) and then I get the list of vertices of that polyhedron using [p.Vrepresentation( )], however the vertices are fractional so is there any way to force the vertices to be 0-1?

If not, is there a way so that I convert the vertices myself?

Thanks and sorry if my question is so basic

I use the Hrep of these points as a part of an MILP model in my optimization problem

My points are all in the form of (0,0,1,0,1,0....0,0) so in each coordinate they take either 0 or 1.

For the number of facets and how degenerate P is, I can't this info a priori, can I?

Thanks,

Hi,

I use the command Polyhedron(vertices = points) where points is an array to create a polyhedron in sage.

It works quite well for dimensions up to 12, i.e., each point in points consists of 12 bits, as the command takes 2-3 minutes even if the size of points is really large.

However, when the dimension increases over 12, things get really slow.

So what is the highest dimension polyhedron that sage can handle?

Thanks,

Hi,

I have created a polyhedron out of a number of vertices and whenever I try to write its H-representation to a file, the inequalities are somehow truncated!

o = open('test.out','w')
for l in triangle.Hrepresentation():
    o.write(str(l) + "\r")

Any idea why is that?

Thanks,