[/============================================================================
  Boost.Geometry (aka GGL, Generic Geometry Library)

  Copyright (c) 2007-2013 Barend Gehrels, Amsterdam, the Netherlands.
  Copyright (c) 2008-2013 Bruno Lalande, Paris, France.
  Copyright (c) 2009-2013 Mateusz Loskot, London, UK.

  Use, modification and distribution is subject to the Boost Software License,
  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  http://www.boost.org/LICENSE_1_0.txt)
=============================================================================/]


[/ Generated by doxygen_xml2qbk 1.1.1, don't change, will be overwritten automatically]
[/ Generated from doxy/doxygen_output/xml/structboost_1_1geometry_1_1radian.xml]
[section:radian radian]

'''<indexterm><primary>radian</primary></indexterm>'''
Unit of plane angle: Radians. 

[heading Description]
Tag defining the unit of plane angle for spherical coordinate systems. This tag specifies that coordinates are defined in radians (-PI .. PI). It has to be specified for some coordinate systems.  

[heading Synopsis]
``struct radian
{
  // ...
};
``

[heading Header]
Either

`#include <boost/geometry.hpp>`


Or

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

[include reference/core/degree_radian.qbk]

[endsect]