CGAL users discussion list

[Martin Baeker <>]

Dear experts,

I just tried to upgrade from CGAL 3.1 to 3.3. (SuSe Linux 10.1 with
g++ (GCC) 4.1.0 (SUSE Linux)) However, I encounter some strange
behaviour when trying to define a function that is named "distance"

#include <iostream>
#include <CGAL/Cartesian.h>
#include <CGAL/Point_2.h>
#include <CGAL/MP_Float.h>
typedef CGAL::Quotient<CGAL::MP_Float>                      NT;
typedef CGAL::Cartesian<NT>                                 TutorialR;
typedef CGAL::Point_2<TutorialR>                             Point;
double distance(const Point & p, const Point & q)
{
  return sqrt(CGAL::to_double(squared_distance(p,q )));
}
int main()
{
  Point p1(1.,2.);
  Point p2(2.,2.);
  std::cout << (distance(p1,p2))  << std::endl;
  return 0;
}

On compiling this, I get

/usr/bin/g++  -Wall -frounding-math 
'-I/home/gecko/martin/fem/abaqus/CGAL-3.3.1/include/CGAL/config/i686_Linux-2.6_g++-4.1.0'
 '-I/home/gecko/martin/fem/abaqus/CGAL-3.3.1/include' -I/usr/X11/include 
-I/usr/lib/qt3/include -g -c -o minitest.o minitest.C 
/usr/include/c++/4.1.0/bits/stl_iterator_base_types.h: In instantiation of 
»std::iterator_traits<CGAL::Point_2<CGAL::Cartesian<CGAL::Quotient<CGAL::MP_Float>
 > > >«:
minitest.C:18:   instantiated from here
/usr/include/c++/4.1.0/bits/stl_iterator_base_types.h:129: Fehler: kein Typ 
namens »iterator_category« in »class 
CGAL::Point_2<CGAL::Cartesian<CGAL::Quotient<CGAL::MP_Float> > >«

As it seems, the function I defined is confused with the std::distance
function, but I do not understand how this happens. If I do the same
thing replacing the Point class with simple doubles, all is well.

Any help, hints, etc are very welcome,

Martin.



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                   Institut für Werkstoffe
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