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 | 1 | initial version |
The current difference between the base ring QQ and ZZ for polyhedron objects in Sage is not quite big nor quite well defined...
A polytope (a compact polyhedron) may have all vertices with integer coordinates, so that it could be called a "Lattice polytope", but its H-representation may still contain rational numbers. Of course, it is possible to multiply all coefficients in the H-representation by a certain integer factor to get an integral H-representation, but this is not automatically done in Sage.
The tickets Add .change_ring() method for polyhedra and Add .change_backend() method for polyhedra will then make it possible to apply the desired changes on the base ring and backend, if possible.
| | 2 | No.2 Revision |
The current difference between the base ring QQ QQ and ZZ ZZ for polyhedron objects in Sage is not quite big nor quite well defined...
A polytope (a compact polyhedron) may have all vertices with integer coordinates, so that it could be called a "Lattice polytope", but its H-representation H-representation may still contain rational numbers. Of course, it is possible to multiply all coefficients in the H-representation H-representation by a certain integer factor to get an integral H-representation, H-representation, but this is not automatically done in Sage.
The tickets Add .change_ring() method for polyhedra and Add .change_backend() method for polyhedra will then make it possible to apply the desired changes on the base ring and backend, if possible.
