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// (C) Copyright Nick Thompson 2020.
// (C) Copyright John Maddock 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 <boost/math/tools/ulps_plot.hpp>
#include <boost/core/demangle.hpp>
#include <boost/multiprecision/mpfr.hpp>
#include <boost/multiprecision/cpp_bin_float.hpp>
using boost::math::tools::ulps_plot;
int main()
{
using PreciseReal = boost::multiprecision::number<boost::multiprecision::mpfr_float_backend<300> >;
using CoarseReal = boost::multiprecision::cpp_bin_float_50;
typedef boost::math::policies::policy<
boost::math::policies::promote_float<false>,
boost::math::policies::promote_double<false> >
no_promote_policy;
auto ai_coarse = [](CoarseReal const& x)->CoarseReal {
return acos(x);
};
auto ai_precise = [](PreciseReal const& x)->PreciseReal {
return acos(x);
};
std::string filename = "cpp_bin_float_acos.svg";
int samples = 100000;
// How many pixels wide do you want your .svg?
int width = 700;
// Near a root, we have unbounded relative error. So for functions with roots, we define an ULP clip:
PreciseReal clip = 20;
// Should we perturb the abscissas?
bool perturb_abscissas = false;
auto plot = ulps_plot<decltype(ai_precise), PreciseReal, CoarseReal>(ai_precise, CoarseReal(-1), CoarseReal(1), samples, perturb_abscissas);
// Note the argument chaining:
plot./*clip(clip).*/width(width);
plot.background_color("white").font_color("black");
// Sometimes it's useful to set a title, but in many cases it's more useful to just use a caption.
std::string title = "acos ULP plot cpp_bin_float_50";
plot.title(title);
plot.vertical_lines(6);
plot.add_fn(ai_coarse);
// You can write the plot to a stream:
//std::cout << plot;
// Or to a file:
plot.write(filename);
}
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