ceph/src/boost/libs/numeric/odeint/test/generic_stepper.cpp

   1 /*
   2  [auto_generated]
   3  libs/numeric/odeint/test/generic_stepper.cpp
   4
   5  [begin_description]
   6  This file tests the generic stepper.
   7  [end_description]
   8
   9  Copyright 2011 Mario Mulansky
  10  Copyright 2012 Karsten Ahnert
  11
  12  Distributed under the Boost Software License, Version 1.0.
  13  (See accompanying file LICENSE_1_0.txt or
  14  copy at http://www.boost.org/LICENSE_1_0.txt)
  15  */
  16
  17 // disable checked iterator warning for msvc
  18 #include <boost/config.hpp>
  19 #ifdef BOOST_MSVC
  20     #pragma warning(disable:4996)
  21 #endif
  22
  23 #define BOOST_TEST_MODULE odeint_generic_stepper
  24
  25 #include <iostream>
  26 #include <utility>
  27
  28 #include <boost/test/unit_test.hpp>
  29
  30 #include <boost/numeric/odeint/stepper/explicit_generic_rk.hpp>
  31 #include <boost/numeric/odeint/stepper/runge_kutta4.hpp>
  32 #include <boost/numeric/odeint/stepper/runge_kutta4_classic.hpp>
  33
  34 #include <boost/array.hpp>
  35
  36 using namespace boost::unit_test;
  37 using namespace boost::numeric::odeint;
  38
  39 namespace fusion = boost::fusion;
  40
  41 typedef double value_type;
  42 typedef boost::array< value_type , 2 > state_type;
  43
  44 void sys( const state_type &x , state_type &dxdt , const value_type &t )
  45 {
  46     dxdt[ 0 ] = x[ 0 ] + 2 * x[ 1 ];
  47     dxdt[ 1 ] = x[ 1 ];
  48 }
  49
  50 typedef explicit_generic_rk< 4 , 4 , state_type> rk_generic_type;
  51 typedef runge_kutta4< state_type > rk4_generic_type;
  52
  53 const boost::array< double , 1 > a1 = {{ 0.5 }};
  54 const boost::array< double , 2 > a2 = {{ 0.0 , 0.5 }};
  55 const boost::array< double , 3 > a3 = {{ 0.0 , 0.0 , 1.0 }};
  56
  57 const rk_generic_type::coef_a_type a = fusion::make_vector( a1 , a2 , a3 );
  58 const rk_generic_type::coef_b_type b = {{ 1.0/6 , 1.0/3 , 1.0/3 , 1.0/6 }};
  59 const rk_generic_type::coef_c_type c = {{ 0.0 , 0.5 , 0.5 , 1.0 }};
  60
  61 typedef runge_kutta4_classic< state_type > rk4_type;
  62
  63 BOOST_AUTO_TEST_SUITE( generic_stepper_test )
  64
  65 BOOST_AUTO_TEST_CASE( test_generic_stepper )
  66 {
  67     //simultaneously test copying
  68     rk_generic_type rk_generic_( a , b , c );
  69     rk_generic_type rk_generic = rk_generic_;
  70
  71     rk4_generic_type rk4_generic_;
  72     rk4_generic_type rk4_generic = rk4_generic_;
  73
  74     //std::cout << stepper;
  75
  76     rk4_type rk4_;
  77     rk4_type rk4 = rk4_;
  78
  79     typedef rk_generic_type::state_type state_type;
  80     typedef rk_generic_type::value_type stepper_value_type;
  81     typedef rk_generic_type::deriv_type deriv_type;
  82     typedef rk_generic_type::time_type time_type;
  83
  84     state_type x = {{ 0.0 , 1.0 }};
  85     state_type y = x;
  86     state_type z = x;
  87
  88     rk_generic.do_step( sys , x , 0.0 , 0.1 );
  89
  90     rk4_generic.do_step( sys , y , 0.0 , 0.1 );
  91
  92     rk4.do_step( sys , z , 0.0 , 0.1 );
  93
  94     BOOST_CHECK_NE( 0.0 , x[0] );
  95     BOOST_CHECK_NE( 1.0 , x[1] );
  96     // compare with analytic solution of above system
  97     BOOST_CHECK_EQUAL( x[0] , y[0] );
  98     BOOST_CHECK_EQUAL( x[1] , y[1] );
  99     BOOST_CHECK_EQUAL( x[0] , z[0] );
 100     BOOST_CHECK_EQUAL( x[1] , z[1] );
 101
 102 }
 103
 104 BOOST_AUTO_TEST_SUITE_END()