blob: 71c0e053b412619335489d7b34fa9e10f32a688c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
|
/*
* Copyright 2011-2012 Mario Mulansky
* Copyright 2012-2013 Karsten Ahnert
*
* 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)
*
* Example for self defined vector type.
*/
#include <vector>
#include <boost/numeric/odeint.hpp>
//[my_vector
template< int MAX_N >
class my_vector
{
typedef std::vector< double > vector;
public:
typedef vector::iterator iterator;
typedef vector::const_iterator const_iterator;
public:
my_vector( const size_t N )
: m_v( N )
{
m_v.reserve( MAX_N );
}
my_vector()
: m_v()
{
m_v.reserve( MAX_N );
}
// ... [ implement container interface ]
//]
const double & operator[]( const size_t n ) const
{ return m_v[n]; }
double & operator[]( const size_t n )
{ return m_v[n]; }
iterator begin()
{ return m_v.begin(); }
const_iterator begin() const
{ return m_v.begin(); }
iterator end()
{ return m_v.end(); }
const_iterator end() const
{ return m_v.end(); }
size_t size() const
{ return m_v.size(); }
void resize( const size_t n )
{ m_v.resize( n ); }
private:
std::vector< double > m_v;
};
//[my_vector_resizeable
// define my_vector as resizeable
namespace boost { namespace numeric { namespace odeint {
template<size_t N>
struct is_resizeable< my_vector<N> >
{
typedef boost::true_type type;
static const bool value = type::value;
};
} } }
//]
typedef my_vector<3> state_type;
void lorenz( const state_type &x , state_type &dxdt , const double t )
{
const double sigma( 10.0 );
const double R( 28.0 );
const double b( 8.0 / 3.0 );
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];
}
using namespace boost::numeric::odeint;
int main()
{
state_type x(3);
x[0] = 5.0 ; x[1] = 10.0 ; x[2] = 10.0;
// my_vector works with range_algebra as it implements
// the required parts of a container interface
// no further work is required
integrate_const( runge_kutta4< state_type >() , lorenz , x , 0.0 , 10.0 , 0.1 );
}
|
