CGAL users discussion list

["Chaman Singh Verma" <>]

On Sat, Nov 29, 2008 at 8:11 PM, Chaman Singh Verma <> wrote:

On Sat, Nov 29, 2008 at 7:43 PM, Sylvain Pion <> wrote:

This was due to a poor choice of kernel in the example program.
This has been fixed since 3.3.1.  Find attached the updated example
program as you will find it in the next CGAL release.

Chaman Singh Verma wrote:

Hello,

I was trying to execute the sample example of ConvexHull in 3D from:

*File: *examples/Convex_hull_3/quickhull_3.cpp

 <http://www.cgal.org/Manual/3.3/examples/Convex_hull_3/quickhull_3.cpp>

and it produces the following message.  What are these and how can I get rid of
them ?

Thanks.
csv
Poona, India


CGAL warning: check violation!
Expr: is_integer(d)
File: /home/csv610/Software/CompGeom/CGAL/include/CGAL/GMP/Gmpz_type.h
Line: 100
Explanation:Gmpz constructed from non-integer double value
CGAL warning: check violation!
Expr: is_integer(d)
File: /home/csv610/Software/CompGeom/CGAL/include/CGAL/GMP/Gmpz_type.h
Line: 100
Explanation:Gmpz constructed from non-integer double value
CGAL warning: check violation!
Expr: is_integer(d)
File: /home/csv610/Software/CompGeom/CGAL/include/CGAL/GMP/Gmpz_type.h
Line: 100
Explanation:Gmpz constructed from non-integer double value
CGAL warning: check violation!
Expr: is_integer(d)

--
Sylvain Pion
INRIA Sophia-Antipolis
Geometrica Project-Team
CGAL, http://cgal.org/

#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/point_generators_3.h>
#include <CGAL/algorithm.h>
#include <CGAL/Convex_hull_traits_3.h>
#include <CGAL/convex_hull_3.h>
#include <vector>


typedef CGAL::Exact_predicates_inexact_constructions_kernel  K;
typedef CGAL::Convex_hull_traits_3<K>             Traits;
typedef Traits::Polyhedron_3                      Polyhedron_3;
typedef K::Segment_3                              Segment_3;

// define point creator
typedef K::Point_3                                Point_3;
typedef CGAL::Creator_uniform_3<double, Point_3>  PointCreator;


int main()
{
 CGAL::Random_points_in_sphere_3<Point_3, PointCreator> gen(100.0);

 // generate 250 points randomly on a sphere of radius 100.0
 // and copy them to a vector
 std::vector<Point_3> points;
 CGAL::copy_n( gen, 250, std::back_inserter(points) );

 // define object to hold convex hull
 CGAL::Object ch_object;

 // compute convex hull
 CGAL::convex_hull_3(points.begin(), points.end(), ch_object);

 // determine what kind of object it is
 if (CGAL::object_cast<Segment_3>(&ch_object) )
    std::cout << "convex hull is a segment " << std::endl;
 else if (CGAL::object_cast<Polyhedron_3>(&ch_object) )
    std::cout << "convex hull is a polyhedron " << std::endl;
 else
    std::cout << "convex hull error!" << std::endl;

 return 0;
}

Hello,

Does this means that we should never use CGAL::Cartesian<double> in future ?

Thanks.
csv

Hello,

With the modifications you made, the code worked. But I have one question, with
this kernel, how we specify the datatype i.e. double, float, int etc ?

Thanks.
csv