On Wednesday, July 7, 2021 at 2:36:27 PM UTC-7 kcrisman wrote: > Normaliz already supports half-open polyhedra, see section 3.12 ("open >> facets") in the Normaliz manual >> see https://github.com/Normaliz/Normaliz/blob/master/doc/Normaliz.pdf >> > > Thank you! But, based on the tickets I've just been cc:ed on, probably > there is no current easy Sage interface for these? >
That's right. You would have to use PyNormaliz directly. Also, it's only certain of the inequalities I would want to be strict - is > that too much to ask? Maybe "Semiopen polyhedra" is more like what I'm > looking for - I do not know the facets, only the inequalities, which in > more complicated examples than the one I provided tend to have nontrivial > interactions. > I think Normaliz only supports the special case of polyhedra with some facets removed, not the more general situation in which you would remove some lower-dimensional faces. This case would still have to be handled using a combination of techniques, including inclusion-exclusion and reciprocity (including the technique of "inside out polytopes"). sage.geometry.polyhedron.modules.FormalPolyhedraModule is a step toward expressing such decomposition and transformation techniques, see https://trac.sagemath.org/ticket/29799 -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-support/b231ea8f-e636-4d51-bbf7-f3e7bce4f328n%40googlegroups.com.