Boost.Range strided

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##### Boost.Range strided

Boost.Range strided range adaptor is adapted to Boost.Geometry

###### Description

Boost.Range strided range adaptor makes a strided range (usually begin a linestring or ring) such that traversal is performed in steps of n.

###### Model of

The Boost.Range strided range adaptor takes over the model of the original geometry, which might be:

- a linestring
- a ring
- a multi_point
- a multi_linestring
- a multi_polygon

###### Header

`#include <boost/geometry/geometries/adapted/boost_range/strided.hpp>`

The standard header `boost/geometry.hpp` does not include this header.

###### Example

Shows how to use a Boost.Geometry ring, strided by Boost.Range adaptor

    #include <iostream>

    #include <boost/assign.hpp>

    #include <boost/geometry.hpp>
    #include <boost/geometry/geometries/point_xy.hpp>
    #include <boost/geometry/geometries/ring.hpp>
    #include <boost/geometry/geometries/adapted/boost_range/strided.hpp>

    int main()
    {
        using namespace boost::assign;
        using boost::adaptors::strided;

        typedef boost::geometry::model::d2::point_xy<int> xy;
        boost::geometry::model::ring<xy> ring;
        ring += xy(0, 0);
        ring += xy(0, 1);
        ring += xy(0, 2);
        ring += xy(1, 2);
        ring += xy(2, 2);
        ring += xy(2, 0);

        boost::geometry::correct(ring);

        std::cout
            << "Normal : " << boost::geometry::dsv(ring) << std::endl
            << "Strided: " << boost::geometry::dsv(ring | strided(2)) << std::endl;

        return 0;
    }

Output:

    Normal : ((0, 0), (0, 1), (0, 2), (1, 2), (2, 2), (2, 0), (0, 0))
    Strided: ((0, 0), (0, 2), (2, 2), (0, 0))