On 02/12/2016 02:00 PM, Bishoksan Kafle wrote:
On Feb 12, 2016, at 8:03 AM, Roberto Bagnara bagnara@cs.unipr.it wrote:
On 02/11/2016 09:17 PM, Bishoksan Kafle wrote:
On Feb 11, 2016, at 8:05 AM, Roberto Bagnara <bagnara@cs.unipr.it mailto:bagnara@cs.unipr.it> wrote:
- In the article
(http://bugseng.com/products/ppl/documentation/BagnaraRZH02.pdf), you mentioned that poly_hull_assign is different from upper_bound_assign for Polyhedra
Where exactly do you read that?
Sorry I wanted to ask the difference between poly-hull and convex-hull. Please ignore my previous question.
The convex polyhedral hull of a set of convex polyhedra P is the smallest convex polyhedron that contains all members of P.
The convex hull of a set of convex polyhedra P is the smallest convex set that contains all members of P.
There exists P such that convex_polyhedral_hull(P) != convex_hull(P). For instance, take P = { p1, p2 } where:
p1 = { (x, y) in R^2 | x = 0 }, p2 = { (x, y) in R^2 | x = 0, y = 1 }.
We have that (1, 1) belongs to convex_polyhedral_hull(P) but (1, 1) does *not* belong to convex_hull(P).
I see your point, but do you mean p2 = { (x, y) in R^2 | x = 1, y = 1 } instead of p2 = { (x, y) in R^2 | x = 0, y = 1 }?
Sorry, I mistyped it by swapping x and y in p2: I meant
p1 = { (x, y) in R^2 | x = 0 }, p2 = { (x, y) in R^2 | x = 1, y = 0 }.
We have that (1, 1) belongs to convex_polyhedral_hull(P) but (1, 1) does *not* belong to convex_hull(P).
Kind regards,
Roberto