260 lines
8.4 KiB
C++
Executable File
260 lines
8.4 KiB
C++
Executable File
// (C) Copyright Gennadiy Rozental 2001-2007.
|
|
// 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)
|
|
|
|
// See http://www.boost.org/libs/test for the library home page.
|
|
//
|
|
// File : $RCSfile$
|
|
//
|
|
// Version : $Revision: 41369 $
|
|
//
|
|
// Description : defines algoirthms for comparing 2 floating point values
|
|
// ***************************************************************************
|
|
|
|
#ifndef BOOST_TEST_FLOATING_POINT_COMPARISON_HPP_071894GER
|
|
#define BOOST_TEST_FLOATING_POINT_COMPARISON_HPP_071894GER
|
|
|
|
#include <boost/limits.hpp> // for std::numeric_limits
|
|
|
|
#include <boost/test/utils/class_properties.hpp>
|
|
|
|
#include <boost/test/detail/suppress_warnings.hpp>
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
namespace boost {
|
|
|
|
namespace test_tools {
|
|
|
|
using unit_test::readonly_property;
|
|
|
|
// ************************************************************************** //
|
|
// ************** floating_point_comparison_type ************** //
|
|
// ************************************************************************** //
|
|
|
|
enum floating_point_comparison_type {
|
|
FPC_STRONG, // "Very close" - equation 1' in docs, the default
|
|
FPC_WEAK // "Close enough" - equation 2' in docs.
|
|
|
|
};
|
|
|
|
// ************************************************************************** //
|
|
// ************** details ************** //
|
|
// ************************************************************************** //
|
|
|
|
namespace tt_detail {
|
|
|
|
// FPT is Floating-Point Type: float, double, long double or User-Defined.
|
|
template<typename FPT>
|
|
inline FPT
|
|
fpt_abs( FPT arg )
|
|
{
|
|
return arg < static_cast<FPT>(0) ? -arg : arg;
|
|
}
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
template<typename FPT>
|
|
struct fpt_limits {
|
|
static FPT min_value()
|
|
{
|
|
return std::numeric_limits<FPT>::is_specialized
|
|
? (std::numeric_limits<FPT>::min)()
|
|
: 0;
|
|
}
|
|
static FPT max_value()
|
|
{
|
|
return std::numeric_limits<FPT>::is_specialized
|
|
? (std::numeric_limits<FPT>::max)()
|
|
: static_cast<FPT>(1000000); // for the our purpuses it doesn't really matter what value is returned here
|
|
}
|
|
};
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
// both f1 and f2 are unsigned here
|
|
template<typename FPT>
|
|
inline FPT
|
|
safe_fpt_division( FPT f1, FPT f2 )
|
|
{
|
|
// Avoid overflow.
|
|
if( f2 < static_cast<FPT>(1) && f1 > f2*fpt_limits<FPT>::max_value() )
|
|
return fpt_limits<FPT>::max_value();
|
|
|
|
// Avoid underflow.
|
|
if( f1 == static_cast<FPT>(0) ||
|
|
f2 > static_cast<FPT>(1) && f1 < f2*fpt_limits<FPT>::min_value() )
|
|
return static_cast<FPT>(0);
|
|
|
|
return f1/f2;
|
|
}
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
} // namespace tt_detail
|
|
|
|
// ************************************************************************** //
|
|
// ************** tolerance presentation types ************** //
|
|
// ************************************************************************** //
|
|
|
|
template<typename FPT>
|
|
struct percent_tolerance_t {
|
|
explicit percent_tolerance_t( FPT v ) : m_value( v ) {}
|
|
|
|
FPT m_value;
|
|
};
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
template<typename Out,typename FPT>
|
|
Out& operator<<( Out& out, percent_tolerance_t<FPT> t )
|
|
{
|
|
return out << t.m_value;
|
|
}
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
template<typename FPT>
|
|
inline percent_tolerance_t<FPT>
|
|
percent_tolerance( FPT v )
|
|
{
|
|
return percent_tolerance_t<FPT>( v );
|
|
}
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
template<typename FPT>
|
|
struct fraction_tolerance_t {
|
|
explicit fraction_tolerance_t( FPT v ) : m_value( v ) {}
|
|
|
|
FPT m_value;
|
|
};
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
template<typename Out,typename FPT>
|
|
Out& operator<<( Out& out, fraction_tolerance_t<FPT> t )
|
|
{
|
|
return out << t.m_value;
|
|
}
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
template<typename FPT>
|
|
inline fraction_tolerance_t<FPT>
|
|
fraction_tolerance( FPT v )
|
|
{
|
|
return fraction_tolerance_t<FPT>( v );
|
|
}
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
// ************************************************************************** //
|
|
// ************** close_at_tolerance ************** //
|
|
// ************************************************************************** //
|
|
|
|
template<typename FPT>
|
|
class close_at_tolerance {
|
|
public:
|
|
// Public typedefs
|
|
typedef bool result_type;
|
|
|
|
// Constructor
|
|
template<typename ToleranceBaseType>
|
|
explicit close_at_tolerance( percent_tolerance_t<ToleranceBaseType> tolerance,
|
|
floating_point_comparison_type fpc_type = FPC_STRONG )
|
|
: p_fraction_tolerance( tt_detail::fpt_abs( static_cast<FPT>(0.01)*tolerance.m_value ) )
|
|
, p_strong_or_weak( fpc_type == FPC_STRONG )
|
|
{}
|
|
template<typename ToleranceBaseType>
|
|
explicit close_at_tolerance( fraction_tolerance_t<ToleranceBaseType> tolerance,
|
|
floating_point_comparison_type fpc_type = FPC_STRONG )
|
|
: p_fraction_tolerance( tt_detail::fpt_abs( tolerance.m_value ) )
|
|
, p_strong_or_weak( fpc_type == FPC_STRONG )
|
|
{}
|
|
|
|
bool operator()( FPT left, FPT right ) const
|
|
{
|
|
FPT diff = tt_detail::fpt_abs( left - right );
|
|
FPT d1 = tt_detail::safe_fpt_division( diff, tt_detail::fpt_abs( right ) );
|
|
FPT d2 = tt_detail::safe_fpt_division( diff, tt_detail::fpt_abs( left ) );
|
|
|
|
return p_strong_or_weak
|
|
? (d1 <= p_fraction_tolerance && d2 <= p_fraction_tolerance)
|
|
: (d1 <= p_fraction_tolerance || d2 <= p_fraction_tolerance);
|
|
}
|
|
|
|
// Public properties
|
|
readonly_property<FPT> p_fraction_tolerance;
|
|
readonly_property<bool> p_strong_or_weak;
|
|
};
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
// ************************************************************************** //
|
|
// ************** check_is_close ************** //
|
|
// ************************************************************************** //
|
|
|
|
struct BOOST_TEST_DECL check_is_close_t {
|
|
// Public typedefs
|
|
typedef bool result_type;
|
|
|
|
template<typename FPT, typename ToleranceBaseType>
|
|
bool
|
|
operator()( FPT left, FPT right, percent_tolerance_t<ToleranceBaseType> tolerance,
|
|
floating_point_comparison_type fpc_type = FPC_STRONG )
|
|
{
|
|
close_at_tolerance<FPT> pred( tolerance, fpc_type );
|
|
|
|
return pred( left, right );
|
|
}
|
|
template<typename FPT, typename ToleranceBaseType>
|
|
bool
|
|
operator()( FPT left, FPT right, fraction_tolerance_t<ToleranceBaseType> tolerance,
|
|
floating_point_comparison_type fpc_type = FPC_STRONG )
|
|
{
|
|
close_at_tolerance<FPT> pred( tolerance, fpc_type );
|
|
|
|
return pred( left, right );
|
|
}
|
|
};
|
|
|
|
namespace {
|
|
check_is_close_t check_is_close;
|
|
}
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
// ************************************************************************** //
|
|
// ************** check_is_small ************** //
|
|
// ************************************************************************** //
|
|
|
|
struct BOOST_TEST_DECL check_is_small_t {
|
|
// Public typedefs
|
|
typedef bool result_type;
|
|
|
|
template<typename FPT>
|
|
bool
|
|
operator()( FPT fpv, FPT tolerance )
|
|
{
|
|
return tt_detail::fpt_abs( fpv ) < tt_detail::fpt_abs( tolerance );
|
|
}
|
|
};
|
|
|
|
namespace {
|
|
check_is_small_t check_is_small;
|
|
}
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
} // namespace test_tools
|
|
|
|
} // namespace boost
|
|
|
|
//____________________________________________________________________________//
|
|
|
|
#include <boost/test/detail/enable_warnings.hpp>
|
|
|
|
#endif // BOOST_FLOATING_POINT_COMAPARISON_HPP_071894GER
|