3dpcp/.svn/pristine/4a/4a0f0c635333464c8a3a3d08079464cf6e9708e2.svn-base
2012-09-16 14:33:11 +02:00

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/// \ingroup newmat
///@{
/// \file precisio.h
/// Floating point precision constants.
#ifndef PRECISION_LIB
#define PRECISION_LIB 0
#define WANT_MATH
#include "include.h" // in case being used as stand alone
#ifdef _STANDARD_ // standard library available
#include <limits>
#endif
#ifdef use_namespace
namespace NEWMAT {
#endif
#ifdef _STANDARD_ // standard library available
#ifdef OPT_COMPATIBLE
#include <cfloat> // for FLT_MAX
#endif
using namespace std;
/// Floating point precision.
class FloatingPointPrecision
{
public:
static int Dig() // number of decimal digits or precision
{ return numeric_limits<Real>::digits10 ; }
static Real Epsilon() // smallest number such that 1+Eps!=Eps
{ return numeric_limits<Real>::epsilon(); }
static int Mantissa() // bits in mantisa
{ return numeric_limits<Real>::digits; }
static Real Maximum() // maximum value
{ return numeric_limits<Real>::max(); }
static int MaximumDecimalExponent() // maximum decimal exponent
{ return numeric_limits<Real>::max_exponent10; }
static int MaximumExponent() // maximum binary exponent
{ return numeric_limits<Real>::max_exponent; }
static Real LnMaximum() // natural log of maximum
{ return (Real)log(Maximum()); }
static Real Minimum() // minimum positive value
{ return numeric_limits<Real>::min(); }
static int MinimumDecimalExponent() // minimum decimal exponent
{ return numeric_limits<Real>::min_exponent10; }
static int MinimumExponent() // minimum binary exponent
{ return numeric_limits<Real>::min_exponent; }
static Real LnMinimum() // natural log of minimum
{ return (Real)log(Minimum()); }
static int Radix() // exponent radix
{ return numeric_limits<Real>::radix; }
static int Rounds() // addition rounding (1 = does round)
{
return numeric_limits<Real>::round_style ==
round_to_nearest ? 1 : 0;
}
};
#else // _STANDARD_ not defined
#ifndef SystemV // if there is float.h
#ifdef USING_FLOAT
/// Floating point precision (type float).
class FloatingPointPrecision
{
public:
static int Dig()
{ return FLT_DIG; } // number of decimal digits or precision
static Real Epsilon()
{ return FLT_EPSILON; } // smallest number such that 1+Eps!=Eps
static int Mantissa()
{ return FLT_MANT_DIG; } // bits in mantisa
static Real Maximum()
{ return FLT_MAX; } // maximum value
static int MaximumDecimalExponent()
{ return FLT_MAX_10_EXP; } // maximum decimal exponent
static int MaximumExponent()
{ return FLT_MAX_EXP; } // maximum binary exponent
static Real LnMaximum()
{ return (Real)log(Maximum()); } // natural log of maximum
static Real Minimum()
{ return FLT_MIN; } // minimum positive value
static int MinimumDecimalExponent()
{ return FLT_MIN_10_EXP; } // minimum decimal exponent
static int MinimumExponent()
{ return FLT_MIN_EXP; } // minimum binary exponent
static Real LnMinimum()
{ return (Real)log(Minimum()); } // natural log of minimum
static int Radix()
{ return FLT_RADIX; } // exponent radix
static int Rounds()
{ return FLT_ROUNDS; } // addition rounding (1 = does round)
};
#endif // USING_FLOAT
#ifdef USING_DOUBLE
/// Floating point precision (type double).
class FloatingPointPrecision
{
public:
static int Dig()
{ return DBL_DIG; } // number of decimal digits or precision
static Real Epsilon()
{ return DBL_EPSILON; } // smallest number such that 1+Eps!=Eps
static int Mantissa()
{ return DBL_MANT_DIG; } // bits in mantisa
static Real Maximum()
{ return DBL_MAX; } // maximum value
static int MaximumDecimalExponent()
{ return DBL_MAX_10_EXP; } // maximum decimal exponent
static int MaximumExponent()
{ return DBL_MAX_EXP; } // maximum binary exponent
static Real LnMaximum()
{ return (Real)log(Maximum()); } // natural log of maximum
static Real Minimum()
{
//#ifdef __BCPLUSPLUS__
// return 2.225074e-308; // minimum positive value
//#else
return DBL_MIN;
//#endif
}
static int MinimumDecimalExponent()
{ return DBL_MIN_10_EXP; } // minimum decimal exponent
static int MinimumExponent()
{ return DBL_MIN_EXP; } // minimum binary exponent
static Real LnMinimum()
{ return (Real)log(Minimum()); } // natural log of minimum
static int Radix()
{ return FLT_RADIX; } // exponent radix
static int Rounds()
{ return FLT_ROUNDS; } // addition rounding (1 = does round)
};
#endif // USING_DOUBLE
#else // if there is no float.h
#ifdef OPT_COMPATIBLE
#define FLT_MAX MAXFLOAT
#endif
#ifdef USING_FLOAT
/// Floating point precision (type float).
class FloatingPointPrecision
{
public:
static Real Epsilon()
{ return pow(2.0,(int)(1-FSIGNIF)); }
// smallest number such that 1+Eps!=Eps
static Real Maximum()
{ return MAXFLOAT; } // maximum value
static Real LnMaximum()
{ return (Real)log(Maximum()); } // natural log of maximum
static Real Minimum()
{ return MINFLOAT; } // minimum positive value
static Real LnMinimum()
{ return (Real)log(Minimum()); } // natural log of minimum
};
#endif // USING_FLOAT
#ifdef USING_DOUBLE
/// Floating point precision (type double).
class FloatingPointPrecision
{
public:
static Real Epsilon()
{ return pow(2.0,(int)(1-DSIGNIF)); }
// smallest number such that 1+Eps!=Eps
static Real Maximum()
{ return MAXDOUBLE; } // maximum value
static Real LnMaximum()
{ return LN_MAXDOUBLE; } // natural log of maximum
static Real Minimum()
{ return MINDOUBLE; }
static Real LnMinimum()
{ return LN_MINDOUBLE; } // natural log of minimum
};
#endif // USING_DOUBLE
#endif // SystemV
#endif // _STANDARD_
#ifdef use_namespace
}
#endif // use_namespace
#endif // PRECISION_LIB
///@}