Fraction type and arithmetic support inclusive its utilization for time without loss of precision nor range. More...

Namespaces
namespace	jau::fraction_tv

namespace	jau::fractions_i64
	fractions namespace to provide fraction constants using int64_t as underlying integral integer type.

namespace	jau::fractions_i64_literals

Classes
struct	jau::FracI64SizeBoolTuple
	Simple pre-defined value pair [fraction_i64, size_t, bool] for structured bindings to multi-values. More...

class	jau::fraction< Int_type, >
	Fraction template type using integral values, evaluated at runtime. More...

struct	jau::fraction_timespec
	Timespec structure using int64_t for its components in analogy to `struct timespec_t` on 64-bit platforms. More...

Typedefs
typedef fraction< int64_t >	jau::fraction_i64
	fraction using int64_t as integral type

typedef fraction< uint64_t >	jau::fraction_u64
	fraction using uint64_t as integral type

typedef ordered_atomic< jau::fraction_i64, std::memory_order_relaxed >	jau::relaxed_atomic_fraction_i64
	Relaxed non-SC atomic integral scalar jau::fraction_i64.

typedef ordered_atomic< jau::fraction_u64, std::memory_order_relaxed >	jau::relaxed_atomic_fraction_u64
	Relaxed non-SC atomic integral scalar jau::fraction_u64.

typedef ordered_atomic< jau::fraction_i64, std::memory_order_seq_cst >	jau::sc_atomic_fraction_i64
	SC atomic integral scalar jau::fraction_i64.

typedef ordered_atomic< jau::fraction_u64, std::memory_order_seq_cst >	jau::sc_atomic_fraction_u64
	SC atomic integral scalar jau::fraction_u64.

Functions
template<typename int_type>
constexpr fraction< int_type >	jau::abs (const fraction< int_type > &rhs) noexcept
	Returns the absolute fraction.

constexpr fraction_timespec	jau::abs (const fraction_timespec &rhs) noexcept
	Returns the absolute fraction_timespec.

fraction_timespec	jau::getMonotonicTime () noexcept
	Returns current monotonic time since Unix Epoch `00:00:00 UTC on 1970-01-01`.

fraction_timespec	jau::getWallClockTime () noexcept
	Returns current wall-clock real-time since Unix Epoch `00:00:00 UTC on 1970-01-01`.

template<typename int_type>
constexpr const fraction< int_type > &	jau::max (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept
	Return the maximum of the two given fractions.

constexpr const fraction_timespec &	jau::max (const fraction_timespec &lhs, const fraction_timespec &rhs) noexcept
	Return the maximum of the two given fraction_timespec.

template<typename int_type>
constexpr const fraction< int_type > &	jau::min (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept
	Return the minimum of the two given fractions.

constexpr const fraction_timespec &	jau::min (const fraction_timespec &lhs, const fraction_timespec &rhs) noexcept
	Return the minimum of the two given fraction_timespec.

template<typename int_type>
constexpr bool	jau::operator!= (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept

template<typename int_type>
constexpr fraction< int_type >	jau::operator* (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept
	Returns product of two fraction.

template<typename int_type>
constexpr fraction< int_type >	jau::operator* (const fraction< int_type > &lhs, const int_type &rhs) noexcept
	Returns multiplication of fraction with scalar.

constexpr fraction_timespec	jau::operator* (const fraction_timespec &lhs, const int64_t rhs) noexcept
	Returns product of fraction_timespec * scalar.

constexpr fraction_timespec	jau::operator* (const int64_t lhs, const fraction_timespec &rhs) noexcept
	Returns product of scalar * fraction_timespec.

template<typename int_type>
constexpr fraction< int_type >	jau::operator* (const int_type &lhs, const fraction< int_type > &rhs) noexcept
	Returns multiplication of fraction with scalar.

template<typename int_type>
constexpr fraction< int_type >	jau::operator+ (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept
	Returns sum of two fraction.

constexpr fraction_timespec	jau::operator+ (const fraction_timespec &lhs, const fraction_timespec &rhs) noexcept
	Returns sum of two fraction_timespec.

template<typename int_type>
constexpr fraction< int_type >	jau::operator- (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept
	Returns difference of two fraction.

constexpr fraction_timespec	jau::operator- (const fraction_timespec &lhs, const fraction_timespec &rhs) noexcept
	Returns difference of two fraction_timespec.

template<typename int_type>
constexpr fraction< int_type >	jau::operator/ (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept
	Returns division of two fraction.

template<typename int_type>
constexpr fraction< int_type >	jau::operator/ (const fraction< int_type > &lhs, const int_type &rhs) noexcept
	Returns division of fraction with scalar.

constexpr fraction_timespec	jau::operator/ (const fraction_timespec &lhs, const int64_t rhs) noexcept
	Returns fraction of fraction_timespec / scalar.

constexpr fraction_timespec	jau::operator/ (const int64_t lhs, const fraction_timespec &rhs) noexcept
	Returns fraction of scalar / fraction_timespec.

template<typename int_type>
constexpr fraction< int_type >	jau::operator/ (const int_type &lhs, const fraction< int_type > &rhs) noexcept
	Returns division of fraction with scalar.

template<typename int_type>
constexpr bool	jau::operator< (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept

template<typename int_type>
constexpr bool	jau::operator<= (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept

template<typename int_type>
constexpr bool	jau::operator== (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept

template<typename int_type>
constexpr bool	jau::operator> (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept

template<typename int_type>
constexpr bool	jau::operator>= (const fraction< int_type > &lhs, const fraction< int_type > &rhs) noexcept

template<typename int_type>
constexpr snsize_t	jau::sign (const fraction< int_type > &rhs) noexcept
	Returns the value of the sign function applied to numerator.

constexpr snsize_t	jau::sign (const fraction_timespec &rhs) noexcept
	Returns the value of the sign function applied to tv_sec.

FracI64SizeBoolTuple	jau::to_fraction_i64 (const std::string &value, const fraction_i64 &min_allowed, const fraction_i64 &max_allowed) noexcept
	Returns the fraction_i64 of the given string in format `<num>/<denom>`, which may contain whitespace.

template<typename int_type>
std::string	jau::to_string (const fraction< int_type > &v) noexcept

std::string	jau::to_string (const fraction_timespec &v) noexcept

Detailed Description

Fraction type and arithmetic support inclusive its utilization for time without loss of precision nor range.

Adds support for Concurrency with general time functionality like sleep_until(), sleep_for(), wait_until() and wait_for(), completed with getMonotonicTime() and getWallClockTime().

Typedef Documentation

◆ fraction_i64

typedef fraction<int64_t> jau::fraction_i64

fraction using int64_t as integral type

Definition at line 737 of file fraction_type.hpp.

◆ fraction_u64

typedef fraction<uint64_t> jau::fraction_u64

fraction using uint64_t as integral type

Definition at line 769 of file fraction_type.hpp.

◆ sc_atomic_fraction_i64

typedef ordered_atomic<jau::fraction_i64, std::memory_order_seq_cst> jau::sc_atomic_fraction_i64

SC atomic integral scalar jau::fraction_i64.

Memory-Model (MM) guaranteed sequential consistency (SC) between acquire (read) and release (write). Requires libatomic with libstdc++10.

Definition at line 1306 of file fraction_type.hpp.

◆ relaxed_atomic_fraction_i64

typedef ordered_atomic<jau::fraction_i64, std::memory_order_relaxed> jau::relaxed_atomic_fraction_i64

Relaxed non-SC atomic integral scalar jau::fraction_i64.

Memory-Model (MM) only guarantees the atomic value, no sequential consistency (SC) between acquire (read) and release (write). Requires libatomic with libstdc++10.

Definition at line 1309 of file fraction_type.hpp.

◆ sc_atomic_fraction_u64

typedef ordered_atomic<jau::fraction_u64, std::memory_order_seq_cst> jau::sc_atomic_fraction_u64

SC atomic integral scalar jau::fraction_u64.

Memory-Model (MM) guaranteed sequential consistency (SC) between acquire (read) and release (write). Requires libatomic with libstdc++10.

Definition at line 1312 of file fraction_type.hpp.

◆ relaxed_atomic_fraction_u64

typedef ordered_atomic<jau::fraction_u64, std::memory_order_relaxed> jau::relaxed_atomic_fraction_u64

Relaxed non-SC atomic integral scalar jau::fraction_u64.

Memory-Model (MM) only guarantees the atomic value, no sequential consistency (SC) between acquire (read) and release (write). Requires libatomic with libstdc++10.

Definition at line 1315 of file fraction_type.hpp.

Function Documentation

◆ getMonotonicTime()

fraction_timespec jau::getMonotonicTime ( )

noexcept

Returns current monotonic time since Unix Epoch 00:00:00 UTC on 1970-01-01.

See http://man7.org/linux/man-pages/man2/clock_gettime.2.html

Returned fraction_timespec is passing machine precision and range of the underlying API.

See fraction_timespec::to_fraction_i64() of how to measure duration in high range and precision:

  fraction_timespec t0 = getMonotonicTime();
  // do something

  // Exact duration
  fraction_timespec td_1 = getMonotonicTime() - t0;

  // or for durations <= 292 years
  fraction_i64 td_2 = (getMonotonicTime() - t0).to_fraction_i64();

This is in stark contract to counting nanoseconds in int64_t which only lasts until 2262-04-12, since INT64_MAX is 9'223'372'036'854'775'807 for 9'223'372'036 seconds or 292 years.

Monotonic time shall be used for high-performance measurements of durations, since the underlying OS shall support fast calls.

See also: fraction_timespec; fraction_timespec::to_fraction_i64(); getWallClockTime()

Regarding avoiding kernel via VDSO, see http://man7.org/linux/man-pages/man7/vdso.7.html, clock_gettime seems to be well supported at least on kernel >= 4.4. Only bfin and sh are missing, while ia64 seems to be complicated.

Definition at line 66 of file basic_types.cpp.

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◆ getWallClockTime()

fraction_timespec jau::getWallClockTime ( )

noexcept

Returns current wall-clock real-time since Unix Epoch 00:00:00 UTC on 1970-01-01.

Returned fraction_timespec is passing machine precision and range of the underlying API.

Wall-Clock time shall be used for accurate measurements of the actual time only, since the underlying OS unlikely supports fast calls.

See also: fraction_timespec; fraction_timespec::to_fraction_i64(); getMonotonicTime()

Definition at line 72 of file basic_types.cpp.

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◆ to_string() [1/2]

template<typename int_type>

std::string jau::to_string ( const fraction< int_type > & v )

inlinenoexcept

Definition at line 547 of file fraction_type.hpp.

◆ operator!=()

template<typename int_type>

bool jau::operator!=	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Definition at line 550 of file fraction_type.hpp.

◆ operator==()

template<typename int_type>

bool jau::operator==	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Definition at line 555 of file fraction_type.hpp.

◆ operator>()

template<typename int_type>

bool jau::operator>	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Definition at line 560 of file fraction_type.hpp.

◆ operator>=()

template<typename int_type>

bool jau::operator>=	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Definition at line 565 of file fraction_type.hpp.

◆ operator<()

template<typename int_type>

bool jau::operator<	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Definition at line 570 of file fraction_type.hpp.

◆ operator<=()

template<typename int_type>

bool jau::operator<=	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Definition at line 575 of file fraction_type.hpp.

◆ max() [1/2]

template<typename int_type>

const fraction< int_type > & jau::max	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Return the maximum of the two given fractions.

Definition at line 581 of file fraction_type.hpp.

◆ min() [1/2]

template<typename int_type>

const fraction< int_type > & jau::min	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Return the minimum of the two given fractions.

Definition at line 587 of file fraction_type.hpp.

◆ sign() [1/2]

template<typename int_type>

snsize_t jau::sign ( const fraction< int_type > & rhs )

constexprnoexcept

Returns the value of the sign function applied to numerator.

-1 for numerator < 0
 0 for numerator = 0
 1 for numerator > 0

Returns: function result

Definition at line 601 of file fraction_type.hpp.

◆ abs() [1/2]

template<typename int_type>

fraction< int_type > jau::abs ( const fraction< int_type > & rhs )

constexprnoexcept

Returns the absolute fraction.

Definition at line 609 of file fraction_type.hpp.

◆ operator*() [1/5]

template<typename int_type>

fraction< int_type > jau::operator*	(	const fraction< int_type > &	lhs,
		const int_type &	rhs )

constexprnoexcept

Returns multiplication of fraction with scalar.

Operation may set the overflow flag in the returned instance, if occurring.

Template Parameters

int_type integral type

Parameters

lhs	the fraction
rhs	the scalar

Returns: resulting new fraction, reduced

Definition at line 626 of file fraction_type.hpp.

◆ operator*() [2/5]

template<typename int_type>

fraction< int_type > jau::operator*	(	const int_type &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Returns multiplication of fraction with scalar.

Operation may set the overflow flag in the returned instance, if occurring.

Template Parameters

int_type integral type

Parameters

lhs	the scalar
rhs	the fraction

Returns: resulting new fraction, reduced

Definition at line 641 of file fraction_type.hpp.

◆ operator/() [1/5]

template<typename int_type>

fraction< int_type > jau::operator/	(	const fraction< int_type > &	lhs,
		const int_type &	rhs )

constexprnoexcept

Returns division of fraction with scalar.

Template Parameters

int_type integral type

Parameters

lhs	the fraction
rhs	the scalar

Returns: resulting new fraction, reduced

Definition at line 653 of file fraction_type.hpp.

◆ operator/() [2/5]

template<typename int_type>

fraction< int_type > jau::operator/	(	const int_type &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Returns division of fraction with scalar.

Template Parameters

int_type integral type

Parameters

lhs	the scalar
rhs	the fraction

Returns: resulting new fraction, reduced

Definition at line 666 of file fraction_type.hpp.

◆ operator+() [1/2]

template<typename int_type>

fraction< int_type > jau::operator+	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Returns sum of two fraction.

Operation may set the overflow flag in the returned instance, if occurring.

Template Parameters

int_type integral type

Parameters

lhs	a fraction
rhs	a fraction

Returns: resulting new fraction, reduced

Definition at line 682 of file fraction_type.hpp.

◆ operator-() [1/2]

template<typename int_type>

fraction< int_type > jau::operator-	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Returns difference of two fraction.

Operation may set the overflow flag in the returned instance, if occurring.

Template Parameters

int_type integral type

Parameters

lhs	a fraction
rhs	a fraction

Returns: resulting new fraction, reduced

Definition at line 699 of file fraction_type.hpp.

◆ operator*() [3/5]

template<typename int_type>

fraction< int_type > jau::operator*	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Returns product of two fraction.

Operation may set the overflow flag in the returned instance, if occurring.

Template Parameters

int_type integral type

Parameters

lhs	a fraction
rhs	a fraction

Returns: resulting new fraction, reduced

Definition at line 716 of file fraction_type.hpp.

◆ operator/() [3/5]

template<typename int_type>

fraction< int_type > jau::operator/	(	const fraction< int_type > &	lhs,
		const fraction< int_type > &	rhs )

constexprnoexcept

Returns division of two fraction.

Template Parameters

int_type integral type

Parameters

lhs	a fraction
rhs	a fraction

Returns: resulting new fraction, reduced

Definition at line 730 of file fraction_type.hpp.

◆ to_fraction_i64()

FracI64SizeBoolTuple jau::to_fraction_i64	(	const std::string &	value,
		const fraction_i64 &	min_allowed,
		const fraction_i64 &	max_allowed )

noexcept

Returns the fraction_i64 of the given string in format <num>/<denom>, which may contain whitespace.

It the given string value does not conform with the format or exceeds the given value range, complete=false is being returned.

If the given string value has been accepted, it is stored in the result reference and complete=true is being returned.

You may use C++17 structured bindings to handle the tuple.

Parameters

value	the string value
min_allowed	the minimum allowed value
max_allowed	the maximum allowed value

Returns: tuple [fraction_i64 result, size_t consumed_chars, bool complete], i.e. complete is true if value has been accepted, otherwise false

Definition at line 960 of file basic_types.cpp.

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◆ to_string() [2/2]

std::string jau::to_string ( const fraction_timespec & v )

inlinenoexcept

Definition at line 1186 of file fraction_type.hpp.

◆ max() [2/2]

const fraction_timespec & jau::max	(	const fraction_timespec &	lhs,
		const fraction_timespec &	rhs )

constexprnoexcept

Return the maximum of the two given fraction_timespec.

Definition at line 1189 of file fraction_type.hpp.

◆ min() [2/2]

const fraction_timespec & jau::min	(	const fraction_timespec &	lhs,
		const fraction_timespec &	rhs )

constexprnoexcept

Return the minimum of the two given fraction_timespec.

Definition at line 1194 of file fraction_type.hpp.

◆ sign() [2/2]

snsize_t jau::sign ( const fraction_timespec & rhs )

constexprnoexcept

Returns the value of the sign function applied to tv_sec.

-1 for numerator < 0
 0 for numerator = 0
 1 for numerator > 0

Returns: function result

Definition at line 1207 of file fraction_type.hpp.

◆ abs() [2/2]

fraction_timespec jau::abs ( const fraction_timespec & rhs )

constexprnoexcept

Returns the absolute fraction_timespec.

Definition at line 1214 of file fraction_type.hpp.

◆ operator+() [2/2]

fraction_timespec jau::operator+	(	const fraction_timespec &	lhs,
		const fraction_timespec &	rhs )

constexprnoexcept

Returns sum of two fraction_timespec.

Parameters

lhs	a fraction_timespec
rhs	a fraction_timespec

Returns: resulting new fraction_timespec, each component reduced and both fraction_timespec::normalize() 'ed

Definition at line 1228 of file fraction_type.hpp.

◆ operator-() [2/2]

fraction_timespec jau::operator-	(	const fraction_timespec &	lhs,
		const fraction_timespec &	rhs )

constexprnoexcept

Returns difference of two fraction_timespec.

See fraction_timespec::to_fraction_i64().

Parameters

lhs	a fraction_timespec
rhs	a fraction_timespec

Returns: resulting new fraction_timespec, each component reduced and both fraction_timespec::normalize() 'ed

Definition at line 1243 of file fraction_type.hpp.

◆ operator*() [4/5]

fraction_timespec jau::operator*	(	const fraction_timespec &	lhs,
		const int64_t	rhs )

constexprnoexcept

Returns product of fraction_timespec * scalar.

Parameters

lhs	a fraction_timespec
rhs	a scalar

Returns: resulting new fraction_timespec, each component reduced and both fraction_timespec::normalize() 'ed

Definition at line 1256 of file fraction_type.hpp.

◆ operator*() [5/5]

fraction_timespec jau::operator*	(	const int64_t	lhs,
		const fraction_timespec &	rhs )

constexprnoexcept

Returns product of scalar * fraction_timespec.

Parameters

lhs	a scalar
rhs	a fraction_timespec

Returns: resulting new fraction_timespec, each component reduced and both fraction_timespec::normalize() 'ed

Definition at line 1268 of file fraction_type.hpp.

◆ operator/() [4/5]

fraction_timespec jau::operator/	(	const fraction_timespec &	lhs,
		const int64_t	rhs )

constexprnoexcept

Returns fraction of fraction_timespec / scalar.

Parameters

lhs	a fraction_timespec
rhs	a scalar

Returns: resulting new fraction_timespec, each component reduced and both fraction_timespec::normalize() 'ed

Definition at line 1280 of file fraction_type.hpp.

◆ operator/() [5/5]

fraction_timespec jau::operator/	(	const int64_t	lhs,
		const fraction_timespec &	rhs )

constexprnoexcept

Returns fraction of scalar / fraction_timespec.

Parameters

lhs	a scalar
rhs	a fraction_timespec

Returns: resulting new fraction_timespec, each component reduced and both fraction_timespec::normalize() 'ed

Definition at line 1292 of file fraction_type.hpp.

Namespaces

Classes

Typedefs

Functions

Detailed Description

Typedef Documentation

◆ fraction_i64

◆ fraction_u64

◆ sc_atomic_fraction_i64

◆ relaxed_atomic_fraction_i64

◆ sc_atomic_fraction_u64

◆ relaxed_atomic_fraction_u64

Function Documentation

◆ getMonotonicTime()

◆ getWallClockTime()

◆ to_string() [1/2]

◆ operator!=()

◆ operator==()

◆ operator>()

◆ operator>=()

◆ operator<()

◆ operator<=()

◆ max() [1/2]

◆ min() [1/2]

◆ sign() [1/2]

◆ abs() [1/2]

◆ operator*() [1/5]

◆ operator*() [2/5]

◆ operator/() [1/5]

◆ operator/() [2/5]

◆ operator+() [1/2]

◆ operator-() [1/2]

◆ operator*() [3/5]

◆ operator/() [3/5]

◆ to_fraction_i64()

◆ to_string() [2/2]

◆ max() [2/2]

◆ min() [2/2]

◆ sign() [2/2]

◆ abs() [2/2]

◆ operator+() [2/2]

◆ operator-() [2/2]

◆ operator*() [4/5]

◆ operator*() [5/5]

◆ operator/() [4/5]

◆ operator/() [5/5]