[PPL-devel] simplifying a constraint system?

[Basile STARYNKEVITCH]

Hello All

[Sorry for the very naive & basic question]

I have constructed some constraint system using the C API. I know I'm 
done constructing it.

Is there some function to "simplify" it or represent it more efficiently?
- perhaps onverting it to NNC_Polyhedron and backwards, using 
ppl_new_NNC_Polyhedron_from_Constraint_System 
<http://www.cs.unipr.it/ppl/Documentation/user/ppl-user-c-interface-0.10-html/interfaceppl__Polyhedron__tag.html#304dd0846a62cb4a9f79806ea82cee5d> 
& ppl_Polyhedron_get_minimuzed_constraints 
<http://www.cs.unipr.it/ppl/Documentation/user/ppl-user-c-interface-0.10-html/interfaceppl__Polyhedron__tag.html#85417db0eb420d402acee4ef0d842efc> 
?
Is there some function to test that it is empty?
- perhaps  using 
<http://www.cs.unipr.it/ppl/Documentation/user/ppl-user-c-interface-0.10-html/interfaceppl__Polyhedron__tag.html#50d5c68064e215d3f2cf3ee69896e676>ppl_new_NNC_Polyhedron_from_Constraint_System 
<http://www.cs.unipr.it/ppl/Documentation/user/ppl-user-c-interface-0.10-html/interfaceppl__Polyhedron__tag.html#304dd0846a62cb4a9f79806ea82cee5d> 
& ppl_Polyhedron_affine_dimension 
<http://www.cs.unipr.it/ppl/Documentation/user/ppl-user-c-interface-0.10-html/interfaceppl__Polyhedron__tag.html#50d5c68064e215d3f2cf3ee69896e676>
A concrete case occuring to me is the constraint system of two variables 
n and y with constraints {n = 10, y = 17, -n >= 0} I need to compute 
that it is empty.

Is there some function to test that it has integer elements, in the 
sense that there exist an integer setting of the variables such as the 
constraint are satisfied?
- perhaps using grids?

Sorry for such basic questions!

Regards.

PS I'm only using the C API!

-- 
Basile STARYNKEVITCH         http://starynkevitch.net/Basile/
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