Re: [Boost-users] boost::geometry::model::linestring

Subject: Re: [Boost-users] boost::geometry::model::linestring
From: Barend Gehrels (barend_at_[hidden])
Date: 2014-05-13 16:11:12

Hi Alev,

alev mutlu wrote On 11-5-2014 14:16:
>
> Hi all,
>
> I have the following code. I can correctly print the content of 
> line_smp with boost::geometry::dsv but get strange results when I copy 
> line_smp into a vector and then print the content of the vector.
>
> Any ideas on what I am doing wrong?
>
> bg::model::d2::point_xy p;
> while(rs->next()){
> bg::set<0>(p, i);
> bg::set<1>(p, rs->getDouble("num"));
> i++;
> line +=p;
> }
> boost::geometry::simplify(line, line_smp, 0.3);
>
> std::cout<<  "  original:"  <<  boost::geometry::dsv(line)  <<  std::endl
>             <<  "simplified:"  <<boost::geometry::dsv(line_smp)  <<  std::endl;
>
>           std::vector<xy>  v;
>           v.clear();
>           std::copy(line_smp.begin(),  line_smp.end(),  std::back_inserter(v));
>
>           stringstream  sa,  ssa;
>           for(int  ia  =  0;  ia  <  v.size();  ia++){
>               sa  <<  bg::get<1>(v[i]);
>               cout<< sa;
>               sa.str("");
>           }

Hard to say, basically the procedure seems OK. I see several things:
- line type is not included in your fragment, what does += for example?
- point type is point_xy or xy?
- you print v[i] while your loop variable is ia (this is probably the 
reason for strange results)

HTH,
Barend