assign_inverse

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##### assign_inverse

assign to a box inverse infinite

###### Description

The assign_inverse function initialize a 2D or 3D box with large coordinates, the min corner is very large, the max corner is very small. This is a convenient starting point to collect the minimum bounding box of a geometry.

###### Synopsis

    template<typename Geometry>
    void assign_inverse(Geometry & geometry)

###### Parameters

Type | Concept | Name | Description
--- | --- | --- | ---
Geometry & | Any type fulfilling a Geometry Concept | geometry | A model of the specified concept

###### Header

Either

`#include <boost/geometry.hpp>`

Or

`#include <boost/geometry/algorithms/assign.hpp>`

###### Example

Usage of assign_inverse and expand to conveniently determine bounding 3D box of two points

    #include <iostream>

    #include <boost/geometry.hpp>
    #include <boost/geometry/geometries/box.hpp>
    #include <boost/geometry/geometries/point.hpp>

    using namespace boost::geometry;

    int main()
    {
        typedef model::point<float, 3, cs::cartesian> point;
        typedef model::box<point> box;

        box all;
        assign_inverse(all);
        std::cout << dsv(all) << std::endl;
        expand(all, point(0, 0, 0));
        expand(all, point(1, 2, 3));
        std::cout << dsv(all) << std::endl;

        return 0;
    }

Output:

    ((3.40282e+038, 3.40282e+038, 3.40282e+038), (-3.40282e+038, -3.40282e+038, -3.40282e+038))
    ((0, 0, 0), (1, 2, 3))

###### See also

- make_inverse