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diff --git a/src/boost/libs/numeric/odeint/examples/heun.cpp b/src/boost/libs/numeric/odeint/examples/heun.cpp
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+/*
+ [auto_generated]
+ libs/numeric/odeint/examples/heun.cpp
+
+ [begin_description]
+ Examplary implementation of the method of Heun.
+ [end_description]
+
+ Copyright 2012 Karsten Ahnert
+ Copyright 2012 Mario Mulansky
+
+ Distributed under 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)
+ */
+
+#include <iostream>
+
+
+#include <boost/fusion/container/vector.hpp>
+#include <boost/fusion/container/generation/make_vector.hpp>
+
+#include <boost/array.hpp>
+
+#include <boost/numeric/odeint.hpp>
+
+
+
+
+
+
+namespace fusion = boost::fusion;
+
+//[ heun_define_coefficients
+template< class Value = double >
+struct heun_a1 : boost::array< Value , 1 > {
+    heun_a1( void )
+    {
+        (*this)[0] = static_cast< Value >( 1 ) / static_cast< Value >( 3 );
+    }
+};
+
+template< class Value = double >
+struct heun_a2 : boost::array< Value , 2 >
+{
+    heun_a2( void )
+    {
+        (*this)[0] = static_cast< Value >( 0 );
+        (*this)[1] = static_cast< Value >( 2 ) / static_cast< Value >( 3 );
+    }
+};
+
+
+template< class Value = double >
+struct heun_b : boost::array< Value , 3 >
+{
+    heun_b( void )
+    {
+        (*this)[0] = static_cast<Value>( 1 ) / static_cast<Value>( 4 );
+        (*this)[1] = static_cast<Value>( 0 );
+        (*this)[2] = static_cast<Value>( 3 ) / static_cast<Value>( 4 );
+    }
+};
+
+template< class Value = double >
+struct heun_c : boost::array< Value , 3 >
+{
+    heun_c( void )
+    {
+        (*this)[0] = static_cast< Value >( 0 );
+        (*this)[1] = static_cast< Value >( 1 ) / static_cast< Value >( 3 );
+        (*this)[2] = static_cast< Value >( 2 ) / static_cast< Value >( 3 );
+    }
+};
+//]
+
+
+//[ heun_stepper_definition
+template<
+    class State ,
+    class Value = double ,
+    class Deriv = State ,
+    class Time = Value ,
+    class Algebra = boost::numeric::odeint::range_algebra ,
+    class Operations = boost::numeric::odeint::default_operations ,
+    class Resizer = boost::numeric::odeint::initially_resizer
+>
+class heun : public
+boost::numeric::odeint::explicit_generic_rk< 3 , 3 , State , Value , Deriv , Time ,
+                                             Algebra , Operations , Resizer >
+{
+
+public:
+
+    typedef boost::numeric::odeint::explicit_generic_rk< 3 , 3 , State , Value , Deriv , Time ,
+                                                         Algebra , Operations , Resizer > stepper_base_type;
+
+    typedef typename stepper_base_type::state_type state_type;
+    typedef typename stepper_base_type::wrapped_state_type wrapped_state_type;
+    typedef typename stepper_base_type::value_type value_type;
+    typedef typename stepper_base_type::deriv_type deriv_type;
+    typedef typename stepper_base_type::wrapped_deriv_type wrapped_deriv_type;
+    typedef typename stepper_base_type::time_type time_type;
+    typedef typename stepper_base_type::algebra_type algebra_type;
+    typedef typename stepper_base_type::operations_type operations_type;
+    typedef typename stepper_base_type::resizer_type resizer_type;
+    typedef typename stepper_base_type::stepper_type stepper_type;
+
+    heun( const algebra_type &algebra = algebra_type() )
+    : stepper_base_type(
+            fusion::make_vector(
+                heun_a1<Value>() ,
+                heun_a2<Value>() ) ,
+            heun_b<Value>() , heun_c<Value>() , algebra )
+    { }
+};
+//]
+
+
+const double sigma = 10.0;
+const double R = 28.0;
+const double b = 8.0 / 3.0;
+
+struct lorenz
+{
+    template< class State , class Deriv >
+    void operator()( const State &x_ , Deriv &dxdt_ , double t ) const
+    {
+        typename boost::range_iterator< const State >::type x = boost::begin( x_ );
+        typename boost::range_iterator< Deriv >::type dxdt = boost::begin( dxdt_ );
+
+        dxdt[0] = sigma * ( x[1] - x[0] );
+        dxdt[1] = R * x[0] - x[1] - x[0] * x[2];
+        dxdt[2] = -b * x[2] + x[0] * x[1];
+    }
+};
+
+struct streaming_observer
+{
+    std::ostream &m_out;
+    streaming_observer( std::ostream &out ) : m_out( out ) { }
+    template< typename State , typename Value >
+    void operator()( const State &x , Value t ) const
+    {
+        m_out << t;
+        for( size_t i=0 ; i<x.size() ; ++i ) m_out << "\t" << x[i];
+        m_out << "\n";
+    }
+};
+
+
+
+int main( int argc , char **argv )
+{
+    using namespace std;
+    using namespace boost::numeric::odeint;
+
+
+    //[ heun_example
+    typedef boost::array< double , 3 > state_type;
+    heun< state_type > h;
+    state_type x = {{ 10.0 , 10.0 , 10.0 }};
+
+    integrate_const( h , lorenz() , x , 0.0 , 100.0 , 0.01 ,
+                     streaming_observer( std::cout ) );
+
+    //]
+
+    return 0;
+}