get

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##### get

Get coordinate value of a geometry (usually a point)

###### Description

The free functions get and set are two of the most important functions of Boost.Geometry, both within the library, as also for the library user. With these two functions you normally get and set coordinate values from and for a point, box, segment or sphere.

###### Synopsis

    template<std::size_t Dimension, typename Geometry>
    coordinate_type<Geometry>::type get(Geometry const & geometry)

###### Parameters

Type | Concept | Name | Description
--- | --- | --- | ---
Dimension | Dimension, this template parameter is required. Should contain [0 .. n-1] for an n-dimensional geometry | - | Must be specified
Geometry const & | Any type fulfilling a Geometry Concept (usually a Point Concept) | geometry | A model of the specified concept (usually a point)

###### Returns

The coordinate value of specified dimension of specified geometry

###### Header

Either

`#include <boost/geometry.hpp>`

Or

`#include <boost/geometry/core/access.hpp>`

###### Behavior

Case | Behavior
--- | ---
Point | Returns the coordinate of a point
Circle or Sphere | Returns the coordinate of the center of a circle or sphere (currently in an extension)
Spherical | Returns the coordinate of a point, in either Radian's or Degree's, depending on specified units

###### Complexity

Constant

###### Example

Get the coordinate of a point

    #include <iostream>

    #include <boost/geometry.hpp>
    #include <boost/geometry/geometries/point_xy.hpp>

    namespace bg = boost::geometry;

    int main()
    {
        bg::model::d2::point_xy<double> point(1, 2);

        double x = bg::get<0>(point);
        double y = bg::get<1>(point);

        std::cout << "x=" << x << " y=" << y << std::endl;

        return 0;
    }

Output:

    x=1 y=2