Re: [PPL-devel] easy way to extract rays from a polyhedron

On 01/14/2017 05:18 PM, John Perry wrote:

I'd like to extract the rays of a polyhedron. As far as I can tell from the documentation, the only way to do this is to extract the generators, then loop over them, testing which is a ray:

Generator_System G = P.generators();
for (Generator g : G)
    if (g.is_ray()) {
        /* party time */
    }

Is there a more direct way to do this, something like G.rays() or even P.rays()?

Hello John,

the snippet above makes lots of unnecessary copies. I would do something like

const Generator_System& G = P.generators(); for (const Generator& g : G) if (g.is_ray()) { /* party time */ }

At party time you can copy `g' if you need to modify the selected ray.

Apart from this, no, there is no more direct way: if it were, it would be implemented along those lines. Kind regards,

Roberto