set (with index)

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##### set (with index)

set coordinate value of a Box / Segment

###### 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 Index, std::size_t Dimension, typename Geometry>
    void set(Geometry & geometry, typename coordinate_type< Geometry >::type const & value)

###### Parameters

Type | Concept | Name | Description
--- | --- | --- | ---
Index | Index, this template parameter is required. For a Box: either min_corner or max_corner. For a Segment: either 0 or 1 for first or last point. | - | Must be specified
Dimension | Dimension, this template parameter is required. Should contain [0 .. n-1] for an n-dimensional geometry | - | Must be specified
Geometry & | Any type fulfilling a Box Concept or a Segment Concept | geometry | A model of the specified concept
typename coordinate_type< Geometry >::type const & |  | value | The coordinate value to set

###### Header

Either

`#include <boost/geometry.hpp>`

Or

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

###### Behavior

Case | Behavior
--- | ---
Box | Sets the coordinate of a box (use min_corner, max_corner to specify which of the points to set)
Segment | Sets the coordinate of a segment (use 0, 1 to specify which of the two points to set)

###### Complexity

Constant

###### Example

Set the coordinate of a box

    #include <iostream>

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

    namespace bg = boost::geometry;

    int main()
    {
        bg::model::box<bg::model::d2::point_xy<double> > box;

        bg::set<bg::min_corner, 0>(box, 0);
        bg::set<bg::min_corner, 1>(box, 2);
        bg::set<bg::max_corner, 0>(box, 4);
        bg::set<bg::max_corner, 1>(box, 5);

        std::cout << "Extent: " << bg::dsv(box) << std::endl;

        return 0;
    }

Output:

    Extent: ((0, 2), (4, 5))