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///////////////////////////////////////////////////////////////
// Copyright 2023 John Maddock. Distributed under the Boost
// Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt
#include <iostream>
#include <iomanip>
#include <boost/multiprecision/fwd.hpp>
//
// Begin by overloading log_postfix_event so we can capture each arithmetic event as it happens,
// unfortunately this must occur BEFORE we include the full header, so just include the forward
// declarations and define our overloads for now. Note that in some cases we may need to just
// declare the overloads here, and define them once the types become concrete:
//
namespace boost::multiprecision {
void log_postfix_event(const cpp_bin_float<113, backends::digit_base_2, void, std::int16_t, -16382, 16383>& val, const char* event_description);
}
//
// Now we can include the actual multiprecision headers and make the types concrete:
//
#include <boost/multiprecision/cpp_bin_float.hpp>
#include <boost/multiprecision/logged_adaptor.hpp>
namespace boost::multiprecision {
bool event_has_been_called = false;
inline void log_postfix_event(const cpp_bin_float<113, backends::digit_base_2, void, std::int16_t, -16382, 16383>& val, const char* event_description)
{
// Print out the (relative) diameter of the interval:
using namespace boost::multiprecision;
event_has_been_called = true;
}
}
int main()
{
using namespace boost::multiprecision;
using logged_type = logged_adaptor_t<cpp_bin_float_quad>;
//
// Test case deliberately introduces cancellation error, relative size of interval
// gradually gets larger after each operation:
//
logged_type a = 1;
a /= 10;
for (unsigned i = 0; i < 13; ++i)
{
logged_type b = a * 9;
b /= 10;
a -= b;
}
std::cout << "Final value was: " << a << std::endl;
return boost::multiprecision::event_has_been_called ? 0 : -1;
}
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