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diff --git a/boost/geometry/algorithms/detail/course.hpp b/boost/geometry/algorithms/detail/course.hpp
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+// Boost.Geometry (aka GGL, Generic Geometry Library)
+
+// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
+
+// This file was modified by Oracle on 2014.
+// Modifications copyright (c) 2014, Oracle and/or its affiliates.
+
+// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
+
+// 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)
+
+#ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_COURSE_HPP
+#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_COURSE_HPP
+
+#include <boost/geometry/core/cs.hpp>
+#include <boost/geometry/core/access.hpp>
+#include <boost/geometry/core/radian_access.hpp>
+#include <boost/geometry/util/math.hpp>
+
+namespace boost { namespace geometry
+{
+
+#ifndef DOXYGEN_NO_DETAIL
+namespace detail
+{
+
+/// Calculate course (bearing) between two points.
+template <typename ReturnType, typename Point1, typename Point2>
+inline ReturnType course(Point1 const& p1, Point2 const& p2)
+{
+    // http://williams.best.vwh.net/avform.htm#Crs
+    ReturnType dlon = get_as_radian<0>(p2) - get_as_radian<0>(p1);
+    ReturnType cos_p2lat = cos(get_as_radian<1>(p2));
+
+    // An optimization which should kick in often for Boxes
+    //if ( math::equals(dlon, ReturnType(0)) )
+    //if ( get<0>(p1) == get<0>(p2) )
+    //{
+    //    return - sin(get_as_radian<1>(p1)) * cos_p2lat);
+    //}
+
+    // "An alternative formula, not requiring the pre-computation of d"
+    // In the formula below dlon is used as "d"
+    return atan2(sin(dlon) * cos_p2lat,
+        cos(get_as_radian<1>(p1)) * sin(get_as_radian<1>(p2))
+        - sin(get_as_radian<1>(p1)) * cos_p2lat * cos(dlon));
+}
+
+} // namespace detail
+#endif // DOXYGEN_NO_DETAIL
+
+}} // namespace boost::geometry
+
+#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_COURSE_HPP