CombinatorialPolyhedron: Check input on errors.

[kliem]

There are a few mistakes one can easily make, when creating a CombinatorialPolyhedron from a list of facets or an incidence matrix. It would be nice to give warnings/error messages about them. Such mistakes can be:

• Not specifying the nr of lines in an unbounded Polyhedron (one knows it is the case, when the vertices in their facet reprsentation are a subset from each other).
• Giving one facet that is actually a list of all vertices.
• Giving an incompatible list of names for vertices and/or facets (maybe too long or too short).
• Checking the facets for inclusions.

Maybe it makes sense to initialize the CombinatorialPolyehdron in C and then do any error checking in terms of inclusion tests. Then a correct input will still be about the same speed and an incorrect input slower.

One could give a warning as "The Polyhedron appears to be unbounded, assuming n number of lines".

Depends on #26887

Component: geometry

Issue created by migration from https://trac.sagemath.org/ticket/27087

[embray]

comment:1

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