On 06/17/11 21:22, Gokul Ramaswamy wrote:

I have understood that, in the polyhedron class, there is a BHRZ03_widening_assign() function which basically does the widening operation. But I am dealing with set of Polyhedrons, so I am using a Powerset class for it. But in the powerset class, I cannot find any widening operator. I want to do widening on my set of polyherdrons. Can someone please point me in the right direction in this regard.

Hi Gokul. for the Pointset_Powerset (applied to any class of polyhedra) you can use BHZ03_widening_assign(). If an extrapolation operator (as opposed to a proper widening operator) is OK for you, there is also BGP99_extrapolation_assign(). Notice though that widening powersets of polyhedra is a rather advanced topic: you really have to read the library documentation. Cheers, Roberto -- Prof. Roberto Bagnara Applied Formal Methods Laboratory Department of Mathematics, University of Parma, Italy http://www.cs.unipr.it/~bagnara/ mailto:bagnara@cs.unipr.it