140 lines
3.6 KiB
C++
Executable File
140 lines
3.6 KiB
C++
Executable File
// Copyright (c) 1999,2007
|
|
// Utrecht University (The Netherlands),
|
|
// ETH Zurich (Switzerland),
|
|
// INRIA Sophia-Antipolis (France),
|
|
// Max-Planck-Institute Saarbruecken (Germany),
|
|
// and Tel-Aviv University (Israel). All rights reserved.
|
|
//
|
|
// This file is part of CGAL (www.cgal.org); you can redistribute it and/or
|
|
// modify it under the terms of the GNU Lesser General Public License as
|
|
// published by the Free Software Foundation; either version 3 of the License,
|
|
// or (at your option) any later version.
|
|
//
|
|
// Licensees holding a valid commercial license may use this file in
|
|
// accordance with the commercial license agreement provided with the software.
|
|
//
|
|
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
|
|
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
|
//
|
|
// $URL$
|
|
// $Id$
|
|
// SPDX-License-Identifier: LGPL-3.0+
|
|
//
|
|
//
|
|
// Author(s) : Geert-Jan Giezeman, Michael Hemmer
|
|
|
|
|
|
#ifndef CGAL_FLOAT_H
|
|
#define CGAL_FLOAT_H
|
|
|
|
#include <CGAL/utils.h>
|
|
#include <CGAL/Algebraic_structure_traits.h>
|
|
#include <CGAL/Real_embeddable_traits.h>
|
|
|
|
#include <cmath> // std::sqrt, std::pow
|
|
|
|
#ifdef CGAL_CFG_IEEE_754_BUG
|
|
# include <CGAL/IEEE_754_unions.h>
|
|
#endif
|
|
|
|
namespace CGAL {
|
|
|
|
#ifdef CGAL_CFG_IEEE_754_BUG
|
|
|
|
#define CGAL_EXPONENT_FLOAT_MASK 0x7f800000
|
|
#define CGAL_MANTISSA_FLOAT_MASK 0x007fffff
|
|
|
|
inline
|
|
bool
|
|
is_finite_by_mask_float(unsigned int u)
|
|
{
|
|
unsigned int e = u & CGAL_EXPONENT_FLOAT_MASK;
|
|
return ( (e ^ CGAL_EXPONENT_FLOAT_MASK) != 0);
|
|
}
|
|
|
|
inline
|
|
bool
|
|
is_nan_by_mask_float(unsigned int u)
|
|
{
|
|
if ( is_finite_by_mask_float(u) ) return false;
|
|
// unsigned int m = u & CGAL_MANTISSA_FLOAT_MASK;
|
|
return ( (u & CGAL_MANTISSA_FLOAT_MASK) != 0);
|
|
}
|
|
|
|
template<>
|
|
class Is_valid< float >
|
|
: public CGAL::cpp98::unary_function< float, bool > {
|
|
public :
|
|
bool operator()( const float& x ) const {
|
|
float f = x;
|
|
IEEE_754_float* p = reinterpret_cast<IEEE_754_float*>(&f);
|
|
return !is_nan_by_mask_float( p->c );
|
|
}
|
|
};
|
|
|
|
#else
|
|
|
|
template<>
|
|
class Is_valid< float >
|
|
: public CGAL::cpp98::unary_function< float, bool > {
|
|
public :
|
|
bool operator()( const float& x ) const {
|
|
return (x == x);
|
|
}
|
|
};
|
|
|
|
#endif
|
|
|
|
template <> class Algebraic_structure_traits< float >
|
|
: public Algebraic_structure_traits_base< float,
|
|
Field_with_kth_root_tag > {
|
|
public:
|
|
typedef Tag_false Is_exact;
|
|
typedef Tag_true Is_numerical_sensitive;
|
|
|
|
class Sqrt
|
|
: public CGAL::cpp98::unary_function< Type, Type > {
|
|
public:
|
|
Type operator()( const Type& x ) const {
|
|
return std::sqrt( x );
|
|
}
|
|
};
|
|
|
|
class Kth_root
|
|
: public CGAL::cpp98::binary_function<int, Type, Type> {
|
|
public:
|
|
Type operator()( int k, const Type& x) const {
|
|
CGAL_precondition_msg( k > 0, "'k' must be positive for k-th roots");
|
|
return (Type) std::pow(double(x), 1.0 / double(k));
|
|
};
|
|
};
|
|
|
|
};
|
|
|
|
template <> class Real_embeddable_traits< float >
|
|
: public INTERN_RET::Real_embeddable_traits_base< float , CGAL::Tag_true> {
|
|
public:
|
|
// Is_finite depends on platform
|
|
class Is_finite
|
|
: public CGAL::cpp98::unary_function< Type, bool > {
|
|
public:
|
|
bool operator()( const Type& x ) const {
|
|
|
|
#if defined CGAL_CFG_IEEE_754_BUG
|
|
Type f = x;
|
|
IEEE_754_float* p = reinterpret_cast<IEEE_754_float*>(&f);
|
|
return is_finite_by_mask_float( p->c );
|
|
#elif !defined CGAL_CFG_NO_CPP0X_ISFINITE
|
|
return std::isfinite(x);
|
|
#else
|
|
return (x == x) && (is_valid(x-x));
|
|
#endif
|
|
}
|
|
};
|
|
|
|
};
|
|
|
|
} //namespace CGAL
|
|
|
|
#endif // CGAL_FLOAT_H
|