1 #include <iostream>
2 #include <boost/array.hpp>
3
4 #include <boost/numeric/odeint.hpp>
5
6 using namespace std;
7 using namespace boost::numeric::odeint;
8
9 const double sigma = 10.0;
10 const double R = 28.0;
11 const double b = 8.0 / 3.0;
12
13 typedef boost::array< double , 3 > state_type;
14
lorenz(const state_type & x,state_type & dxdt,double t)15 void lorenz( const state_type &x , state_type &dxdt , double t )
16 {
17 dxdt[0] = sigma * ( x[1] - x[0] );
18 dxdt[1] = R * x[0] - x[1] - x[0] * x[2];
19 dxdt[2] = -b * x[2] + x[0] * x[1];
20 }
21
write_lorenz(const state_type & x,const double t)22 void write_lorenz( const state_type &x , const double t )
23 {
24 cout << t << '\t' << x[0] << '\t' << x[1] << '\t' << x[2] << endl;
25 }
26
main(int argc,char ** argv)27 int main(int argc, char **argv)
28 {
29 state_type x = {{ 10.0 , 1.0 , 1.0 }}; // initial conditions
30 integrate( lorenz , x , 0.0 , 25.0 , 0.1 , write_lorenz );
31 }
32