2021-10-05 21:37:46 +02:00

36 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 <boost/multiprecision/mpfr.hpp>
#include <boost/multiprecision/float128.hpp>
#include <boost/multiprecision/cpp_bin_float.hpp>
#include <boost/math/tools/ulps_plot.hpp>
#include <boost/math/special_functions/rsqrt.hpp>
int main()
{
using boost::multiprecision::number;
using PreciseReal = number<boost::multiprecision::mpfr_float_backend<1000>>;
using CoarseReal = boost::multiprecision::float128;
using boost::math::tools::ulps_plot;
std::string filename = "rsqrt_quad_0_100.svg";
int samples = 2500;
int width = 1100;
auto f = [](PreciseReal x) {
using boost::math::rsqrt;
return rsqrt(x);
};
auto plot03 = ulps_plot<decltype(f), PreciseReal, CoarseReal>(f, std::numeric_limits<CoarseReal>::min(), CoarseReal(100), samples);
plot03.width(width);
std::string title = "rsqrt ULPs plot at quad precision";
plot03.title(title);
plot03.vertical_lines(6);
auto g = [](CoarseReal x) {
return boost::math::rsqrt(x);
};
plot03.add_fn(g);
plot03.write(filename);
}