mirror of
https://github.com/saitohirga/WSJT-X.git
synced 2025-11-03 21:40:52 -05:00
152 lines
4.0 KiB
C++
152 lines
4.0 KiB
C++
/*
|
|
[auto_generated]
|
|
libs/numeric/odeint/examples/black_hole.cpp
|
|
|
|
[begin_description]
|
|
This example shows how the __float128 from gcc libquadmath can be used with odeint.
|
|
[end_description]
|
|
|
|
Copyright 2012 Karsten Ahnert
|
|
Copyright 2012 Lee Hodgkinson
|
|
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 <cstdlib>
|
|
#include <cmath>
|
|
#include <iostream>
|
|
#include <iterator>
|
|
#include <utility>
|
|
#include <algorithm>
|
|
#include <cassert>
|
|
#include <vector>
|
|
#include <complex>
|
|
|
|
extern "C" {
|
|
#include <quadmath.h>
|
|
}
|
|
|
|
const __float128 zero =strtoflt128 ("0.0", NULL);
|
|
|
|
namespace std {
|
|
|
|
inline __float128 abs( __float128 x )
|
|
{
|
|
return fabsq( x );
|
|
}
|
|
|
|
inline __float128 sqrt( __float128 x )
|
|
{
|
|
return sqrtq( x );
|
|
}
|
|
|
|
inline __float128 pow( __float128 x , __float128 y )
|
|
{
|
|
return powq( x , y );
|
|
}
|
|
|
|
inline __float128 abs( std::complex< __float128 > x )
|
|
{
|
|
return sqrtq( x.real() * x.real() + x.imag() * x.imag() );
|
|
}
|
|
|
|
inline std::complex< __float128 > pow( std::complex< __float128> x , __float128 y )
|
|
{
|
|
__float128 r = pow( abs(x) , y );
|
|
__float128 phi = atanq( x.imag() / x.real() );
|
|
return std::complex< __float128 >( r * cosq( y * phi ) , r * sinq( y * phi ) );
|
|
}
|
|
}
|
|
|
|
inline std::ostream& operator<< (std::ostream& os, const __float128& f) {
|
|
|
|
char* y = new char[1000];
|
|
quadmath_snprintf(y, 1000, "%.30Qg", f) ;
|
|
os.precision(30);
|
|
os<<y;
|
|
delete[] y;
|
|
return os;
|
|
}
|
|
|
|
|
|
#include <boost/array.hpp>
|
|
#include <boost/range/algorithm.hpp>
|
|
#include <boost/range/adaptor/filtered.hpp>
|
|
#include <boost/range/numeric.hpp>
|
|
#include <boost/numeric/odeint.hpp>
|
|
|
|
|
|
|
|
using namespace boost::numeric::odeint;
|
|
using namespace std;
|
|
|
|
typedef __float128 my_float;
|
|
typedef std::vector< std::complex < my_float > > state_type;
|
|
|
|
struct radMod
|
|
{
|
|
my_float m_om;
|
|
my_float m_l;
|
|
|
|
radMod( my_float om , my_float l )
|
|
: m_om( om ) , m_l( l ) { }
|
|
|
|
void operator()( const state_type &x , state_type &dxdt , my_float r ) const
|
|
{
|
|
|
|
dxdt[0] = x[1];
|
|
dxdt[1] = -(2*(r-1)/(r*(r-2)))*x[1]-((m_om*m_om*r*r/((r-2)*(r-2)))-(m_l*(m_l+1)/(r*(r-2))))*x[0];
|
|
}
|
|
};
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
int main( int argc , char **argv )
|
|
{
|
|
|
|
|
|
state_type x(2);
|
|
|
|
my_float re0 = strtoflt128( "-0.00008944230755601224204687038354994353820468" , NULL );
|
|
my_float im0 = strtoflt128( "0.00004472229441850588228136889483397204368247" , NULL );
|
|
my_float re1 = strtoflt128( "-4.464175354293244250869336196695966076150E-6 " , NULL );
|
|
my_float im1 = strtoflt128( "-8.950483248390306670770345406051469584488E-6" , NULL );
|
|
|
|
x[0] = complex< my_float >( re0 ,im0 );
|
|
x[1] = complex< my_float >( re1 ,im1 );
|
|
|
|
const my_float dt =strtoflt128 ("-0.001", NULL);
|
|
const my_float start =strtoflt128 ("10000.0", NULL);
|
|
const my_float end =strtoflt128 ("9990.0", NULL);
|
|
const my_float omega =strtoflt128 ("2.0", NULL);
|
|
const my_float ell =strtoflt128 ("1.0", NULL);
|
|
|
|
|
|
|
|
my_float abs_err = strtoflt128( "1.0E-15" , NULL ) , rel_err = strtoflt128( "1.0E-10" , NULL );
|
|
my_float a_x = strtoflt128( "1.0" , NULL ) , a_dxdt = strtoflt128( "1.0" , NULL );
|
|
|
|
typedef runge_kutta_dopri5< state_type, my_float > dopri5_type;
|
|
typedef controlled_runge_kutta< dopri5_type > controlled_dopri5_type;
|
|
typedef dense_output_runge_kutta< controlled_dopri5_type > dense_output_dopri5_type;
|
|
|
|
dense_output_dopri5_type dopri5( controlled_dopri5_type( default_error_checker< my_float >( abs_err , rel_err , a_x , a_dxdt ) ) );
|
|
|
|
std::for_each( make_adaptive_time_iterator_begin(dopri5 , radMod(omega , ell) , x , start , end , dt) ,
|
|
make_adaptive_time_iterator_end(dopri5 , radMod(omega , ell) , x ) ,
|
|
[]( const std::pair< state_type&, my_float > &x ) {
|
|
std::cout << x.second << ", " << x.first[0].real() << "\n"; }
|
|
);
|
|
|
|
|
|
|
|
return 0;
|
|
}
|