CGAL users discussion list

[Andreas Fabri <>]

Just increase the precision.

std::cout.precision(17);
before you write the points to the stream.

http://www.cplusplus.com/reference/iomanip/setprecision/

best,

andreas

On 24/09/2014 19:09, Илья Палачев wrote:
> Hi,
> I'm using convex_hull_3 with Exact_predicates_inexact_constructions_kernel.
> The function returns polyhedron with the following vertices:
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #0: (-8.660254e-01, -5.000000e-01, 0.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #1: (-8.660254e-01, -5.000000e-01, -0.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #2: (-0.000000e+00, -0.000000e+00, 1.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #3: (-0.000000e+00, -0.000000e+00, -1.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #4: (-0.000000e+00, -1.000000e+00, -0.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #5: (-8.660254e-01, 5.000000e-01, -0.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #6: (-8.660254e-01, 5.000000e-01, -0.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #7: (8.660254e-01, 5.000000e-01, -0.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #8: (8.660254e-01, 5.000000e-01, 0.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #9: (8.660254e-01, -5.000000e-01, -0.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #10: (-0.000000e+00, 1.000000e+00, -0.000000e+00)
> [Polyhedron_3 convexHullCGAL(CGALpointsSet): 594]: convex hull's point
> #11: (8.660254e-01, -5.000000e-01, -0.000000e+00)
> As you can see some of points are equal, and this makes its analysis
> complex.
> Is there any setting in convex_hull_3 that can help to avoid such situation?
> Best regards,
> Ilya Palachev

--
Andreas Fabri, PhD
Chief Officer, GeometryFactory
Editor, The CGAL Project

phone: +33.492.954.912    skype: andreas.fabri