id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
12929,linestring with zero points or a single point is not equal to itself,Michael Maier <m-maier@…>,Barend Gehrels,"I expect a linestring with zero points or a single point is equal to itself. However, this is not the case for {{{boost::geometry::equals}}} even though the documentation says

  Checks if a geometry are spatially equal.

  Spatially equal means that the same point set is included.

I expect a linestring with zero points to be equal to all empty point sets. I expect a linestring with a single point to be equal to all single point sets where the single points are equal.


{{{
#!div style=""font-size: 80%""
Example:
  {{{#!c++
#include <iostream>

#include <boost/geometry.hpp>

namespace bg = boost::geometry;

using point = bg::model::point<double, 2, bg::cs::cartesian>;
using linestring = bg::model::linestring<point>;

int main() {
    linestring empty;
    linestring single_point_linestring {{0.0, 0.0}};
    linestring single_point_linestring_2 {{0.0, 0.0}};

    std::cout << ""empty == empty := "" << bg::equals(empty, empty) << '\n';
    std::cout << ""single_point_linestring == single_point_linestring := ""
              << bg::equals(single_point_linestring, single_point_linestring) << '\n';
    std::cout << ""single_point_linestring == single_point_linestring_2 := ""
              << bg::equals(single_point_linestring, single_point_linestring_2) << '\n';
}
  }}}
}}}

{{{
#!div style=""font-size: 80%""
Output:
{{{
empty == empty := 0
single_point_linestring == single_point_linestring := 0
single_point_linestring == single_point_linestring_2 := 0
}}}
}}}


{{{
#!div style=""font-size: 80%""
Expected:
{{{
empty == empty := 1
single_point_linestring == single_point_linestring := 1
single_point_linestring == single_point_linestring_2 := 1
}}}
}}}
",Bugs,new,To Be Determined,geometry,Boost 1.60.0,Problem,,,