Teuchos::ScalarTraits< T > Struct Template Reference

This structure defines some basic traits for a scalar field type. More...

#include <Teuchos_ScalarTraitsDecl.hpp>

List of all members.

Public Types

typedef T magnitudeType
 Mandatory typedef for result of magnitude.
typedef T halfPrecision
 Typedef for half precision.
typedef T doublePrecision
 Typedef for double precision.

Static Public Member Functions

static magnitudeType eps ()
 Returns relative machine precision.
static magnitudeType sfmin ()
 Returns safe minimum (sfmin), such that 1/sfmin does not overflow.
static magnitudeType base ()
 Returns the base of the machine.
static magnitudeType prec ()
 Returns eps*base.
static magnitudeType t ()
 Returns the number of (base) digits in the mantissa.
static magnitudeType rnd ()
 Returns 1.0 when rounding occurs in addition, 0.0 otherwise.
static magnitudeType emin ()
 Returns the minimum exponent before (gradual) underflow.
static magnitudeType rmin ()
 Returns the underflow threshold - base^(emin-1).
static magnitudeType emax ()
 Returns the largest exponent before overflow.
static magnitudeType rmax ()
 Overflow theshold - (base^emax)*(1-eps).
static magnitudeType magnitude (T a)
 Returns the magnitudeType of the scalar type a.
static T zero ()
 Returns representation of zero for this scalar type.
static T one ()
 Returns representation of one for this scalar type.
static magnitudeType real (T a)
 Returns the real part of the scalar type a.
static magnitudeType imag (T a)
 Returns the imaginary part of the scalar type a.
static T conjugate (T a)
 Returns the conjugate of the scalar type a.
static T nan ()
 Returns a number that represents NaN.
static bool isnaninf (const T &x)
 Returns true if x is NaN or Inf.
static void seedrandom (unsigned int s)
 Seed the random number generator returned by random().
static T random ()
 Returns a random number (between -one() and +one()) of this scalar type.
static std::string name ()
 Returns the name of this scalar type.
static T squareroot (T x)
 Returns a number of magnitudeType that is the square root of this scalar type x.
static T pow (T x, T y)
 Returns the result of raising one scalar x to the power y.

Static Public Attributes

static const bool isComplex = false
 Determines if scalar type is std::complex.
static const bool isOrdinal = false
 Determines if scalar type is an ordinal type.
static const bool isComparable = false
 Determines if scalar type supports relational operators such as <, >, <=, >=.
static const bool hasMachineParameters = false
 Determines if scalar type have machine-specific parameters (i.e. eps(), sfmin(), base(), prec(), t(), rnd(), emin(), rmin(), emax(), rmax() are supported).


Detailed Description

template<typename T>
struct Teuchos::ScalarTraits< T >

This structure defines some basic traits for a scalar field type.

Scalar traits are an essential part of templated codes. This structure offers the basic traits of the templated scalar type, like defining zero and one, and basic functions on the templated scalar type, like performing a square root.

The functions in the templated base unspecialized struct are designed not to compile (giving a nice compile-time error message) and therefore specializations must be written for Scalar types actually used.

Note:
  1. The default defined specializations are provided for int, float, and double.

  2. If Teuchos is configured with Teuchos_ENABLE_COMPLEX=ON then ScalarTraits also has a parital specialization for all std::complex numbers of the form std::complex<T>.

Definition at line 76 of file Teuchos_ScalarTraitsDecl.hpp.


Member Typedef Documentation

template<typename T>
typedef T Teuchos::ScalarTraits< T >::magnitudeType

Mandatory typedef for result of magnitude.

Definition at line 79 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
typedef T Teuchos::ScalarTraits< T >::halfPrecision

Typedef for half precision.

Definition at line 81 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
typedef T Teuchos::ScalarTraits< T >::doublePrecision

Typedef for double precision.

Definition at line 83 of file Teuchos_ScalarTraitsDecl.hpp.


Member Function Documentation

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::eps (  )  [inline, static]

Returns relative machine precision.

Definition at line 96 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::sfmin (  )  [inline, static]

Returns safe minimum (sfmin), such that 1/sfmin does not overflow.

Definition at line 98 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::base (  )  [inline, static]

Returns the base of the machine.

Definition at line 100 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::prec (  )  [inline, static]

Returns eps*base.

Definition at line 102 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::t (  )  [inline, static]

Returns the number of (base) digits in the mantissa.

Definition at line 104 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::rnd (  )  [inline, static]

Returns 1.0 when rounding occurs in addition, 0.0 otherwise.

Definition at line 106 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::emin (  )  [inline, static]

Returns the minimum exponent before (gradual) underflow.

Definition at line 108 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::rmin (  )  [inline, static]

Returns the underflow threshold - base^(emin-1).

Definition at line 110 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::emax (  )  [inline, static]

Returns the largest exponent before overflow.

Definition at line 112 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::rmax (  )  [inline, static]

Overflow theshold - (base^emax)*(1-eps).

Definition at line 114 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::magnitude ( a  )  [inline, static]

Returns the magnitudeType of the scalar type a.

Definition at line 116 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static T Teuchos::ScalarTraits< T >::zero (  )  [inline, static]

Returns representation of zero for this scalar type.

Definition at line 118 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static T Teuchos::ScalarTraits< T >::one (  )  [inline, static]

Returns representation of one for this scalar type.

Definition at line 120 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::real ( a  )  [inline, static]

Returns the real part of the scalar type a.

Definition at line 122 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static magnitudeType Teuchos::ScalarTraits< T >::imag ( a  )  [inline, static]

Returns the imaginary part of the scalar type a.

Definition at line 124 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static T Teuchos::ScalarTraits< T >::conjugate ( a  )  [inline, static]

Returns the conjugate of the scalar type a.

Definition at line 126 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static T Teuchos::ScalarTraits< T >::nan (  )  [inline, static]

Returns a number that represents NaN.

Definition at line 128 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static bool Teuchos::ScalarTraits< T >::isnaninf ( const T &  x  )  [inline, static]

Returns true if x is NaN or Inf.

Definition at line 130 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static void Teuchos::ScalarTraits< T >::seedrandom ( unsigned int  s  )  [inline, static]

Seed the random number generator returned by random().

Definition at line 132 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static T Teuchos::ScalarTraits< T >::random (  )  [inline, static]

Returns a random number (between -one() and +one()) of this scalar type.

Definition at line 134 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static std::string Teuchos::ScalarTraits< T >::name (  )  [inline, static]

Returns the name of this scalar type.

Definition at line 136 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static T Teuchos::ScalarTraits< T >::squareroot ( x  )  [inline, static]

Returns a number of magnitudeType that is the square root of this scalar type x.

Definition at line 138 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
static T Teuchos::ScalarTraits< T >::pow ( x,
y 
) [inline, static]

Returns the result of raising one scalar x to the power y.

Definition at line 140 of file Teuchos_ScalarTraitsDecl.hpp.


Member Data Documentation

template<typename T>
const bool Teuchos::ScalarTraits< T >::isComplex = false [static]

Determines if scalar type is std::complex.

Definition at line 85 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
const bool Teuchos::ScalarTraits< T >::isOrdinal = false [static]

Determines if scalar type is an ordinal type.

Definition at line 87 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
const bool Teuchos::ScalarTraits< T >::isComparable = false [static]

Determines if scalar type supports relational operators such as <, >, <=, >=.

Definition at line 89 of file Teuchos_ScalarTraitsDecl.hpp.

template<typename T>
const bool Teuchos::ScalarTraits< T >::hasMachineParameters = false [static]

Determines if scalar type have machine-specific parameters (i.e. eps(), sfmin(), base(), prec(), t(), rnd(), emin(), rmin(), emax(), rmax() are supported).

Definition at line 94 of file Teuchos_ScalarTraitsDecl.hpp.


The documentation for this struct was generated from the following file:
Generated on Tue Jul 13 09:23:02 2010 for Teuchos - Trilinos Tools Package by  doxygen 1.4.7