boost/libs/math/example/cohen_acceleration.cpp
2021-10-05 21:37:46 +02:00

47 lines
1.3 KiB
C++

// (C) Copyright Nick Thompson 2020.
// Use, modification and distribution are subject to 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 <iomanip>
#include <boost/math/tools/cohen_acceleration.hpp>
#include <boost/math/constants/constants.hpp>
using boost::math::tools::cohen_acceleration;
using boost::math::constants::pi;
template<typename Real>
class G {
public:
G(){
k_ = 0;
}
Real operator()() {
k_ += 1;
return 1/(k_*k_);
}
private:
Real k_;
};
int main() {
using Real = float;
auto g = G<Real>();
Real computed = cohen_acceleration(g);
Real expected = pi<Real>()*pi<Real>()/12;
std::cout << std::setprecision(std::numeric_limits<Real>::max_digits10);
std::cout << "Computed = " << computed << " = " << std::hexfloat << computed << "\n";
std::cout << std::defaultfloat;
std::cout << "Expected = " << expected << " = " << std::hexfloat << expected << "\n";
// Compute with a specified number of terms:
// Make sure to reset g:
g = G<Real>();
computed = cohen_acceleration(g, 5);
std::cout << std::defaultfloat;
std::cout << "Computed = " << computed << " = " << std::hexfloat << computed << " using 5 terms.\n";
}