fixed_point <--> floating-point conversion functions. More...

#include <cudf/utilities/export.hpp>
#include <cudf/utilities/traits.hpp>
#include <cuda/std/cmath>
#include <cuda/std/limits>
#include <cuda/std/type_traits>
#include <cstring>

Classes
struct	numeric::detail::floating_converter< FloatingType, >
	Helper struct for getting and setting the components of a floating-point value. More...

struct	numeric::detail::shifting_constants< FloatingType >
	Helper struct with common constants needed by the floating <--> decimal conversions. More...

Namespaces
	numeric
	`fixed_point` and supporting types

Functions
template<typename T , CUDF_ENABLE_IF(std::is_same_v< T, uint32_t >\|\|std::is_same_v< T, uint64_t >\|\| std::is_same_v< T, __uint128_t >) >
CUDF_HOST_DEVICE int	numeric::detail::count_significant_bits (T value)
	Determine the number of significant bits in an integer. More...

template<int Pow10>
constexpr __uint128_t	numeric::detail::large_power_of_10 ()
	Recursively calculate a signed large power of 10 (>= 10^19) that can only be stored in an 128bit integer. More...

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >
CUDF_HOST_DEVICE T	numeric::detail::divide_power10_32bit (T value, int pow10)
	Divide by a power of 10 that fits within a 32bit integer. More...

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >
CUDF_HOST_DEVICE T	numeric::detail::divide_power10_64bit (T value, int pow10)
	Divide by a power of 10 that fits within a 64bit integer. More...

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >
constexpr CUDF_HOST_DEVICE T	numeric::detail::divide_power10_128bit (T value, int pow10)
	Divide by a power of 10 that fits within a 128bit integer. More...

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >
constexpr CUDF_HOST_DEVICE T	numeric::detail::multiply_power10_32bit (T value, int pow10)
	Multiply by a power of 10 that fits within a 32bit integer. More...

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >
constexpr CUDF_HOST_DEVICE T	numeric::detail::multiply_power10_64bit (T value, int pow10)
	Multiply by a power of 10 that fits within a 64bit integer. More...

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >
constexpr CUDF_HOST_DEVICE T	numeric::detail::multiply_power10_128bit (T value, int pow10)
	Multiply by a power of 10 that fits within a 128bit integer. More...

template<typename Rep , typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >
constexpr CUDF_HOST_DEVICE T	numeric::detail::multiply_power10 (T value, int pow10)
	Multiply an integer by a power of 10. More...

template<typename Rep , typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >
constexpr CUDF_HOST_DEVICE T	numeric::detail::divide_power10 (T value, int pow10)
	Divide an integer by a power of 10. More...

template<typename IntegerType , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< IntegerType >) >
CUDF_HOST_DEVICE IntegerType	numeric::detail::guarded_left_shift (IntegerType value, int bit_shift)
	Perform a bit-shift left, guarding against undefined behavior. More...

template<typename IntegerType , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< IntegerType >) >
CUDF_HOST_DEVICE IntegerType	numeric::detail::guarded_right_shift (IntegerType value, int bit_shift)
	Perform a bit-shift right, guarding against undefined behavior. More...

template<typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >
CUDF_HOST_DEVICE cuda::std::pair< typename floating_converter< FloatingType >::IntegralType, int >	numeric::detail::add_half_if_truncates (FloatingType floating, typename floating_converter< FloatingType >::IntegralType integer_rep, int pow2, int pow10)
	Add half a bit to integer rep of floating point if conversion causes truncation. More...

template<typename Rep , typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >
CUDF_HOST_DEVICE cuda::std::make_unsigned_t< Rep >	numeric::detail::shift_to_decimal_pospow (typename shifting_constants< FloatingType >::IntegerRep const base2_value, int pow2, int pow10)
	Perform base-2 -> base-10 fixed-point conversion for pow10 > 0. More...

template<typename Rep , typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >
CUDF_HOST_DEVICE cuda::std::make_unsigned_t< Rep >	numeric::detail::shift_to_decimal_negpow (typename shifting_constants< FloatingType >::IntegerRep base2_value, int pow2, int pow10)
	Perform base-2 -> base-10 fixed-point conversion for pow10 < 0. More...

template<typename Rep , typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >
CUDF_HOST_DEVICE cuda::std::make_unsigned_t< Rep >	numeric::detail::convert_floating_to_integral_shifting (typename floating_converter< FloatingType >::IntegralType base2_value, int pow10, int pow2)
	Perform base-2 -> base-10 fixed-point conversion. More...

template<typename Rep , typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >
CUDF_HOST_DEVICE Rep	numeric::detail::convert_floating_to_integral (FloatingType const &floating, scale_type const &scale)
	Perform floating-point -> integer decimal conversion. More...

template<typename FloatingType , typename DecimalRep , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >
CUDF_HOST_DEVICE auto	numeric::detail::shift_to_binary_pospow (DecimalRep decimal_rep, int pow10)
	Perform base-10 -> base-2 fixed-point conversion for pow10 > 0. More...

template<typename FloatingType , typename DecimalRep , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >
CUDF_HOST_DEVICE auto	numeric::detail::shift_to_binary_negpow (DecimalRep decimal_rep, int const pow10)
	Perform base-10 -> base-2 fixed-point conversion for pow10 < 0. More...

template<typename FloatingType , typename Rep , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >
CUDF_HOST_DEVICE FloatingType	numeric::detail::convert_integral_to_floating (Rep const &value, scale_type const &scale)
	Perform integer decimal -> floating-point conversion. More...

Detailed Description

fixed_point <--> floating-point conversion functions.

Definition in file floating_conversion.hpp.

Function Documentation

◆ add_half_if_truncates()

template<typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >

CUDF_HOST_DEVICE cuda::std::pair<typename floating_converter<FloatingType>::IntegralType, int> numeric::detail::add_half_if_truncates	(	FloatingType	floating,
		typename floating_converter< FloatingType >::IntegralType	integer_rep,
		int	pow2,
		int	pow10
	)

Add half a bit to integer rep of floating point if conversion causes truncation.

Note: This fixes problems like 1.2 (value = 1.1999...) at scale -1 -> 11

Template Parameters

FloatingType Type of integer holding the floating-point significand

Parameters

floating	The floating-point number to convert
integer_rep	The integer representation of the floating-point significand
pow2	The power of 2 that needs to be applied to the significand
pow10	The power of 10 that needs to be applied to the significand

Returns: integer_rep, shifted 1 and ++'d if the conversion to decimal causes truncation

Definition at line 636 of file floating_conversion.hpp.

◆ convert_floating_to_integral()

template<typename Rep , typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >

CUDF_HOST_DEVICE Rep numeric::detail::convert_floating_to_integral	(	FloatingType const &	floating,
		scale_type const &	scale
	)

inline

Perform floating-point -> integer decimal conversion.

Template Parameters

Rep	The type of integer we are converting to, to store the decimal value
FloatingType	The type of floating-point object we are converting from

Parameters

floating	The floating point value to convert
scale	The desired base-10 scale factor: decimal value = returned value * 10^scale

Returns: Integer representation of the floating-point value, given the desired scale

Definition at line 932 of file floating_conversion.hpp.

◆ convert_floating_to_integral_shifting()

template<typename Rep , typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >

CUDF_HOST_DEVICE cuda::std::make_unsigned_t<Rep> numeric::detail::convert_floating_to_integral_shifting	(	typename floating_converter< FloatingType >::IntegralType	base2_value,
		int	pow10,
		int	pow2
	)

inline

Perform base-2 -> base-10 fixed-point conversion.

Template Parameters

Rep	The type of integer we are converting to, to store the decimal value
FloatingType	The type of floating-point object we are converting from

Parameters

base2_value	The base-2 fixed-point value we are converting from
pow2	The number of powers of 2 to apply to convert from base-2
pow10	The number of powers of 10 to apply to reach the desired scale factor

Returns: Integer representation of the floating-point value, given the desired scale

Definition at line 880 of file floating_conversion.hpp.

◆ convert_integral_to_floating()

template<typename FloatingType , typename Rep , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >

CUDF_HOST_DEVICE FloatingType numeric::detail::convert_integral_to_floating	(	Rep const &	value,
		scale_type const &	scale
	)

inline

Perform integer decimal -> floating-point conversion.

Template Parameters

FloatingType	The type of floating-point object we are converting to
Rep	The decimal integer type we are converting from

Parameters

value	The decimal integer to convert
scale	The base-10 scale factor for the input integer

Returns: Floating-point representation of the scaled integral value

Definition at line 1101 of file floating_conversion.hpp.

◆ count_significant_bits()

template<typename T , CUDF_ENABLE_IF(std::is_same_v< T, uint32_t >||std::is_same_v< T, uint64_t >|| std::is_same_v< T, __uint128_t >) >

CUDF_HOST_DEVICE int numeric::detail::count_significant_bits ( T value )

inline

Determine the number of significant bits in an integer.

Template Parameters

T	Type of input integer value. Must be either uint32_t, uint64_t, or __uint128_t

Parameters

value The integer whose bits are being counted

Returns: The number of significant bits: the # of bits - # of leading zeroes

Definition at line 49 of file floating_conversion.hpp.

◆ divide_power10()

template<typename Rep , typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >

constexpr CUDF_HOST_DEVICE T numeric::detail::divide_power10	(	T	value,
		int	pow10
	)

inlineconstexpr

Divide an integer by a power of 10.

Note: Use this function if you have no a-priori knowledge of what pow10 might be. If you do, prefer calling the bit-size-specific versions

Template Parameters

Rep	Representation type needed for integer exponentiation
T	Integral type of value to be divided-from.

Parameters

value	The number to be divided-from.
pow10	The power-of-10 of the denominator.

Returns: Returns value / 10^pow10

Definition at line 507 of file floating_conversion.hpp.

◆ divide_power10_128bit()

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >

constexpr CUDF_HOST_DEVICE T numeric::detail::divide_power10_128bit	(	T	value,
		int	pow10
	)

inlineconstexpr

Divide by a power of 10 that fits within a 128bit integer.

Template Parameters

T	Type of value to be divided-from.

Parameters

value	The number to be divided-from.
pow10	The power-of-10 of the denominator, from 0 to 38 inclusive.

Returns: Returns value / 10^pow10.

Definition at line 408 of file floating_conversion.hpp.

◆ divide_power10_32bit()

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >

CUDF_HOST_DEVICE T numeric::detail::divide_power10_32bit	(	T	value,
		int	pow10
	)

inline

Divide by a power of 10 that fits within a 32bit integer.

Template Parameters

T	Type of value to be divided-from.

Parameters

value	The number to be divided-from.
pow10	The power-of-10 of the denominator, from 0 to 9 inclusive.

Returns: Returns value / 10^pow10

Definition at line 344 of file floating_conversion.hpp.

◆ divide_power10_64bit()

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >

CUDF_HOST_DEVICE T numeric::detail::divide_power10_64bit	(	T	value,
		int	pow10
	)

inline

Divide by a power of 10 that fits within a 64bit integer.

Template Parameters

T	Type of value to be divided-from.

Parameters

value	The number to be divided-from.
pow10	The power-of-10 of the denominator, from 0 to 19 inclusive.

Returns: Returns value / 10^pow10

Definition at line 394 of file floating_conversion.hpp.

◆ guarded_left_shift()

template<typename IntegerType , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< IntegerType >) >

CUDF_HOST_DEVICE IntegerType numeric::detail::guarded_left_shift	(	IntegerType	value,
		int	bit_shift
	)

inline

Perform a bit-shift left, guarding against undefined behavior.

Template Parameters

IntegerType Type of input unsigned integer value

Parameters

value	The integer whose bits are being shifted
bit_shift	The number of bits to shift left

Returns: The bit-shifted integer, except max value if UB would occur

Definition at line 529 of file floating_conversion.hpp.

◆ guarded_right_shift()

template<typename IntegerType , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< IntegerType >) >

CUDF_HOST_DEVICE IntegerType numeric::detail::guarded_right_shift	(	IntegerType	value,
		int	bit_shift
	)

inline

Perform a bit-shift right, guarding against undefined behavior.

Template Parameters

IntegerType Type of input unsigned integer value

Parameters

value	The integer whose bits are being shifted
bit_shift	The number of bits to shift right

Returns: The bit-shifted integer, which is zero on underflow

Definition at line 546 of file floating_conversion.hpp.

◆ large_power_of_10()

template<int Pow10>

constexpr __uint128_t numeric::detail::large_power_of_10 ( )

constexpr

Recursively calculate a signed large power of 10 (>= 10^19) that can only be stored in an 128bit integer.

Note: Intended to be run at compile time.

Template Parameters

Pow10 The power of 10 to calculate

Returns: Returns 10^Pow10

Definition at line 325 of file floating_conversion.hpp.

◆ multiply_power10()

template<typename Rep , typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >

constexpr CUDF_HOST_DEVICE T numeric::detail::multiply_power10	(	T	value,
		int	pow10
	)

inlineconstexpr

Multiply an integer by a power of 10.

Note: Use this function if you have no a-priori knowledge of what pow10 might be. If you do, prefer calling the bit-size-specific versions

Template Parameters

Rep	Representation type needed for integer exponentiation
T	Integral type of value to be multiplied.

Parameters

value	The number to be multiplied.
pow10	The power-of-10 of the multiplier.

Returns: Returns value * 10^pow10

Definition at line 481 of file floating_conversion.hpp.

◆ multiply_power10_128bit()

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >

constexpr CUDF_HOST_DEVICE T numeric::detail::multiply_power10_128bit	(	T	value,
		int	pow10
	)

inlineconstexpr

Multiply by a power of 10 that fits within a 128bit integer.

Template Parameters

T	Type of value to be multiplied.

Parameters

value	The number to be multiplied.
pow10	The power-of-10 of the multiplier, from 0 to 38 inclusive.

Returns: Returns value * 10^pow10.

Definition at line 463 of file floating_conversion.hpp.

◆ multiply_power10_32bit()

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >

constexpr CUDF_HOST_DEVICE T numeric::detail::multiply_power10_32bit	(	T	value,
		int	pow10
	)

inlineconstexpr

Multiply by a power of 10 that fits within a 32bit integer.

Template Parameters

T	Type of value to be multiplied.

Parameters

value	The number to be multiplied.
pow10	The power-of-10 of the multiplier, from 0 to 9 inclusive.

Returns: Returns value * 10^pow10

Definition at line 422 of file floating_conversion.hpp.

◆ multiply_power10_64bit()

template<typename T , CUDF_ENABLE_IF(cuda::std::is_unsigned_v< T >) >

constexpr CUDF_HOST_DEVICE T numeric::detail::multiply_power10_64bit	(	T	value,
		int	pow10
	)

inlineconstexpr

Multiply by a power of 10 that fits within a 64bit integer.

Template Parameters

T	Type of value to be multiplied.

Parameters

value	The number to be multiplied.
pow10	The power-of-10 of the multiplier, from 0 to 19 inclusive.

Returns: Returns value * 10^pow10

Definition at line 449 of file floating_conversion.hpp.

◆ shift_to_binary_negpow()

template<typename FloatingType , typename DecimalRep , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >

CUDF_HOST_DEVICE auto numeric::detail::shift_to_binary_negpow	(	DecimalRep	decimal_rep,
		int const	pow10
	)

inline

Perform base-10 -> base-2 fixed-point conversion for pow10 < 0.

Template Parameters

DecimalRep	The decimal integer type we are converting from
FloatingType	The type of floating point object we are converting to

Parameters

decimal_rep	The decimal integer to convert
pow10	The number of powers of 10 to apply to undo the scale factor

Returns: A pair of the base-2 value and the remaining powers of 2 to be applied

Definition at line 1034 of file floating_conversion.hpp.

◆ shift_to_binary_pospow()

template<typename FloatingType , typename DecimalRep , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >

CUDF_HOST_DEVICE auto numeric::detail::shift_to_binary_pospow	(	DecimalRep	decimal_rep,
		int	pow10
	)

inline

Perform base-10 -> base-2 fixed-point conversion for pow10 > 0.

Template Parameters

DecimalRep	The decimal integer type we are converting from
FloatingType	The type of floating point object we are converting to

Parameters

decimal_rep	The decimal integer to convert
pow10	The number of powers of 10 to apply to undo the scale factor

Returns: A pair of the base-2 value and the remaining powers of 2 to be applied

Definition at line 971 of file floating_conversion.hpp.

◆ shift_to_decimal_negpow()

template<typename Rep , typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >

CUDF_HOST_DEVICE cuda::std::make_unsigned_t<Rep> numeric::detail::shift_to_decimal_negpow	(	typename shifting_constants< FloatingType >::IntegerRep	base2_value,
		int	pow2,
		int	pow10
	)

inline

Perform base-2 -> base-10 fixed-point conversion for pow10 < 0.

Template Parameters

Rep	The type of the storage for the decimal value
FloatingType	The type of the original floating-point value we are converting from

Parameters

base2_value	The base-2 fixed-point value we are converting from
pow2	The number of powers of 2 to apply to convert from base-2
pow10	The number of powers of 10 to apply to reach the desired scale factor

Returns: Magnitude of the converted-to decimal integer

Definition at line 794 of file floating_conversion.hpp.

◆ shift_to_decimal_pospow()

template<typename Rep , typename FloatingType , CUDF_ENABLE_IF(cuda::std::is_floating_point_v< FloatingType >) >

CUDF_HOST_DEVICE cuda::std::make_unsigned_t<Rep> numeric::detail::shift_to_decimal_pospow	(	typename shifting_constants< FloatingType >::IntegerRep const	base2_value,
		int	pow2,
		int	pow10
	)

inline

Perform base-2 -> base-10 fixed-point conversion for pow10 > 0.

Template Parameters

Rep	The type of the storage for the decimal value
FloatingType	The type of the original floating-point value we are converting from

Parameters

base2_value	The base-2 fixed-point value we are converting from
pow2	The number of powers of 2 to apply to convert from base-2
pow10	The number of powers of 10 to apply to reach the desired scale factor

Returns: Magnitude of the converted-to decimal integer

Definition at line 707 of file floating_conversion.hpp.

Classes

Namespaces

Functions

Detailed Description

Function Documentation

◆ add_half_if_truncates()

◆ convert_floating_to_integral()

◆ convert_floating_to_integral_shifting()

◆ convert_integral_to_floating()

◆ count_significant_bits()

◆ divide_power10()

◆ divide_power10_128bit()

◆ divide_power10_32bit()

◆ divide_power10_64bit()

◆ guarded_left_shift()

◆ guarded_right_shift()

◆ large_power_of_10()

◆ multiply_power10()

◆ multiply_power10_128bit()

◆ multiply_power10_32bit()

◆ multiply_power10_64bit()

◆ shift_to_binary_negpow()

◆ shift_to_binary_pospow()

◆ shift_to_decimal_negpow()

◆ shift_to_decimal_pospow()