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- /* Boost libs/numeric/odeint/examples/integrate_times.cpp
- Copyright 2009-2014 Karsten Ahnert
- Copyright 2009-2014 Mario Mulansky
- example for the use of integrate_times
- 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/numeric/odeint.hpp>
- using namespace std;
- using namespace boost::numeric::odeint;
- /*
- * simple 1D ODE
- */
- void rhs( const double x , double &dxdt , const double t )
- {
- dxdt = 3.0/(2.0*t*t) + x/(2.0*t);
- }
- void write_cout( const double &x , const double t )
- {
- cout << t << '\t' << x << endl;
- }
- // state_type = double
- typedef runge_kutta_dopri5< double > stepper_type;
- const double dt = 0.1;
- int main()
- {
- // create a vector with observation time points
- std::vector<double> times( 91 );
- for( size_t i=0 ; i<times.size() ; ++i )
- times[i] = 1.0 + dt*i;
- double x = 0.0; //initial value x(1) = 0
- // we can provide the observation time as a boost range (i.e. the vector)
- integrate_times( make_controlled( 1E-12 , 1E-12 , stepper_type() ) , rhs ,
- x , times , dt , write_cout );
- // or as two iterators
- //integrate_times( make_controlled( 1E-12 , 1E-12 , stepper_type() ) , rhs ,
- // x , times.begin() , times.end() , dt , write_cout );
- }
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