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half_float::half Class Reference

#include <half.hpp>

Public Member Functions

HALF_CONSTEXPR half ()
 
 half (detail::expr rhs)
 
 half (float rhs)
 
 operator float () const
 
halfoperator= (detail::expr rhs)
 
template<typename T >
detail::enable< half &, T >::type operator+= (T rhs)
 
template<typename T >
detail::enable< half &, T >::type operator-= (T rhs)
 
template<typename T >
detail::enable< half &, T >::type operator*= (T rhs)
 
template<typename T >
detail::enable< half &, T >::type operator/= (T rhs)
 
halfoperator= (float rhs)
 
halfoperator+= (float rhs)
 
halfoperator-= (float rhs)
 
halfoperator*= (float rhs)
 
halfoperator/= (float rhs)
 
halfoperator++ ()
 
halfoperator-- ()
 
half operator++ (int)
 
half operator-- (int)
 

Friends

struct detail::functions
 
struct detail::unary_specialized< half >
 
struct detail::binary_specialized< half, half >
 
template<typename , typename , std::float_round_style >
struct detail::half_caster
 
class std::numeric_limits< half >
 

Detailed Description

Half-precision floating point type. This class implements an IEEE-conformant half-precision floating point type with the usual arithmetic operators and conversions. It is implicitly convertible to single-precision floating point, which makes artihmetic expressions and functions with mixed-type operands to be of the most precise operand type. Additionally all arithmetic operations (and many mathematical functions) are carried out in single-precision internally. All conversions from single- to half-precision are done using truncation (round towards zero), but temporary results inside chained arithmetic expressions are kept in single-precision as long as possible (while of course still maintaining a strong half-precision type).

According to the C++98/03 definition, the half type is not a POD type. But according to C++11's less strict and extended definitions it is both a standard layout type and a trivially copyable type (even if not a POD type), which means it can be standard-conformantly copied using raw binary copies. But in this context some more words about the actual size of the type. Although the half is representing an IEEE 16-bit type, it does not neccessarily have to be of exactly 16-bits size. But on any reasonable implementation the actual binary representation of this type will most probably not ivolve any additional "magic" or padding beyond the simple binary representation of the underlying 16-bit IEEE number, even if not strictly guaranteed by the standard. But even then it only has an actual size of 16 bits if your C++ implementation supports an unsigned integer type of exactly 16 bits width. But this should be the case on nearly any reasonable platform.

So if your C++ implementation is not totally exotic or imposes special alignment requirements, it is a reasonable assumption that the data of a half is just comprised of the 2 bytes of the underlying IEEE representation.

Constructor & Destructor Documentation

◆ half() [1/3]

HALF_CONSTEXPR half_float::half::half ( )
inline

Default constructor. This initializes the half to 0. Although this does not match the builtin types' default-initialization semantics and may be less efficient than no initialization, it is needed to provide proper value-initialization semantics.

◆ half() [2/3]

half_float::half::half ( detail::expr  rhs)
inline

Copy constructor.

Template Parameters
Ttype of concrete half expression
Parameters
rhshalf expression to copy from

◆ half() [3/3]

half_float::half::half ( float  rhs)
inlineexplicit

Conversion constructor.

Parameters
rhsfloat to convert

Member Function Documentation

◆ operator float()

half_float::half::operator float ( ) const
inline

Conversion to single-precision.

Returns
single precision value representing expression value

◆ operator*=() [1/2]

half& half_float::half::operator*= ( float  rhs)
inline

Arithmetic assignment.

Parameters
rhssingle-precision value to multiply with
Returns
reference to this half

◆ operator*=() [2/2]

template<typename T >
detail::enable<half&,T>::type half_float::half::operator*= ( rhs)
inline

Arithmetic assignment.

Template Parameters
Ttype of concrete half expression
Parameters
rhshalf expression to multiply with
Returns
reference to this half

◆ operator++() [1/2]

half& half_float::half::operator++ ( )
inline

Prefix increment.

Returns
incremented half value

◆ operator++() [2/2]

half half_float::half::operator++ ( int  )
inline

Postfix increment.

Returns
non-incremented half value

◆ operator+=() [1/2]

half& half_float::half::operator+= ( float  rhs)
inline

Arithmetic assignment.

Parameters
rhssingle-precision value to add
Returns
reference to this half

◆ operator+=() [2/2]

template<typename T >
detail::enable<half&,T>::type half_float::half::operator+= ( rhs)
inline

Arithmetic assignment.

Template Parameters
Ttype of concrete half expression
Parameters
rhshalf expression to add
Returns
reference to this half

◆ operator--() [1/2]

half& half_float::half::operator-- ( )
inline

Prefix decrement.

Returns
decremented half value

◆ operator--() [2/2]

half half_float::half::operator-- ( int  )
inline

Postfix decrement.

Returns
non-decremented half value

◆ operator-=() [1/2]

half& half_float::half::operator-= ( float  rhs)
inline

Arithmetic assignment.

Parameters
rhssingle-precision value to subtract
Returns
reference to this half

◆ operator-=() [2/2]

template<typename T >
detail::enable<half&,T>::type half_float::half::operator-= ( rhs)
inline

Arithmetic assignment.

Template Parameters
Ttype of concrete half expression
Parameters
rhshalf expression to subtract
Returns
reference to this half

◆ operator/=() [1/2]

half& half_float::half::operator/= ( float  rhs)
inline

Arithmetic assignment.

Parameters
rhssingle-precision value to divide by
Returns
reference to this half

◆ operator/=() [2/2]

template<typename T >
detail::enable<half&,T>::type half_float::half::operator/= ( rhs)
inline

Arithmetic assignment.

Template Parameters
Ttype of concrete half expression
Parameters
rhshalf expression to divide by
Returns
reference to this half

◆ operator=() [1/2]

half& half_float::half::operator= ( detail::expr  rhs)
inline

Assignment operator.

Template Parameters
Ttype of concrete half expression
Parameters
rhshalf expression to copy from
Returns
reference to this half

◆ operator=() [2/2]

half& half_float::half::operator= ( float  rhs)
inline

Assignment operator.

Parameters
rhssingle-precision value to copy from
Returns
reference to this half

The documentation for this class was generated from the following file: