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Calculates the centroid of a geometry using the specified strategy.
The free function centroid calculates the geometric center (or: center of mass) of a geometry. This version with the return_ prefix returns the centroid, and a template parameter must therefore be specified in the call.. Reasons to specify a strategy include: use another coordinate system for calculations; construct the strategy beforehand (e.g. with the radius of the Earth); select a strategy when there are more than one available for a calculation.
template<typename Point, typename Geometry, typename Strategy> Point return_centroid(Geometry const & geometry, Strategy const & strategy)
| Type | Concept | Name | Description | 
|---|---|---|---|
| Point | Any type fulfilling a Point Concept | - | Must be specified | 
| Geometry const & | Any type fulfilling a Geometry Concept | geometry | A model of the specified concept | 
| Strategy const & | Any type fulfilling a centroid Strategy Concept | strategy | The strategy which will be used for centroid calculations | 
The calculated centroid
Either
            #include <boost/geometry.hpp>
          
Or
            #include <boost/geometry/algorithms/centroid.hpp>
          
The function centroid implements function Centroid from the OGC Simple Feature Specification.
| Case | Behavior | 
|---|---|
| Point | Returns the point itself as the centroid | 
| Multi Point | Calculates centroid (based on average) | 
| linear (e.g. linestring) | Calculates centroid (based on weighted length) | 
| areal (e.g. polygon) | Calculates centroid | 
| Empty (e.g. polygon without points) | Throws a centroid_exception | 
| Cartesian | Implemented | 
| Spherical | Calculates the centroid as if based on Cartesian coordinates | 
| 2D | 3D | |
|---|---|---|
| Point | 
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| Segment | 
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| Box | 
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| Linestring | 
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| Ring | 
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| Polygon | 
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| MultiPoint | 
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| MultiLinestring | 
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| MultiPolygon | 
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Linear