...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Strategy to calculate the distance between two boxes.
template<typename CalculationType> class strategy::distance::pythagoras_box_box { // ... };
Parameter 
Default 
Description 

typename CalculationType 
void 
numeric type for calculation (e.g. high precision); if void then it is extracted automatically from the coordinate type and (if necessary) promoted to floating point 
Function 
Description 
Parameters 
Returns 

template<typename Box1, typename Box2> calculation_type< Box1, Box2 >::type apply(Box1 const & box1, Box2 const & box2)

applies the distance calculation using pythagoras_box_box 
Box1 const &: box1: first box Box2 const &: box2: second box 
the calculated distance (including taking the square root) 
#include <boost/geometry/strategies/cartesian/distance_pythagoras_box_box.hpp>
Note  

Can be used for boxes with two, three or more dimensions 