Quantity Source Code
github: quantity.hpp @github.com
/** @file quantity.hpp
*
* Author: Roland Conybeare
**/
#pragma once
#include "quantity_ops.hpp"
#include "natural_unit.hpp"
#include "scaled_unit.hpp"
#include "scaled_unit_concept.hpp"
namespace xo {
namespace qty {
/** @class quantity
*
* @brief represent a scalar quantity with associated units.
*
* - @p NaturalUnit is a non-type template paramoeter
* identifying a unit used for this quantity.
* In *xo-unit* it will be an instance of @c natural_unit
* - @p Repr is a type used to represent a multiple
* of @p NaturalUnit.
*
* Enforce dimensional consistency at compile time.
* sizeof(quantity) == sizeof(Repr).
*
* A quantity's runtime state consists of exactly one @p Repr instance:
* @code
* sizeof(quantity<NaturalUnit, Repr>) == sizeof(Repr)
* @endcode
**/
template <
auto ScaledUnit,
typename Repr = double>
requires (ScaledUnit.is_natural() && ScaledUnit.is_scaled_unit_type())
class quantity {
public:
/** @defgroup quantity-type-traits quantity type traits **/
///@{
/** @brief runtime representation for value of this type **/
using repr_type = Repr;
/** @brief type used to represent unit information */
using unit_type = decltype(ScaledUnit);
/** @brief type used for numerator and denominator in basis-unit scalefactor ratios */
using ratio_int_type = unit_type::ratio_int_type;
/** @brief double-width type used for numerator and denominator of intermediate
* scalefactor ratios. Used to mitigate loss of precision during computation
* of conversion factors between units with widely-differing magnitude
**/
using ratio_int2x_type = detail::width2x_t<typename unit_type::ratio_int_type>;
///@}
public:
/** @defgroup quantity-ctors quantity constructors**/
///@{
/** @brief create a zero amount with dimension @c ScaledUnit **/
constexpr quantity() : scale_{0} {}
/** @brief create a quantity representing @p scale @c ScaledUnits **/
explicit constexpr quantity(Repr scale) : scale_{scale} {}
///@}
/** @defgroup quantity-constants static quantity constants **/
///@{
/** @brief Use to distinguish @ref quantity from xquantity instances.
*
* Useful in c++ template resolution.
**/
static constexpr bool always_constexpr_unit = true;
///@}
/** @defgroup quantity-access-methods quantity access methods **/
///@{
/** @brief value of @c scale_ in quantity representing amount (@c scale_ * @c s_unit) **/
constexpr const repr_type & scale() const { return scale_; }
/** @brief s_unit in quantity representing amount (@c scale_ * @c s_unit) **/
constexpr const unit_type & unit() const { return s_scaled_unit; }
/** @brief true iff this quantity represents a dimensionless value **/
static constexpr bool is_dimensionless() {
return s_scaled_unit.is_dimensionless();
}
/** abbreviated suffix for quantities with this unit **/
constexpr nu_abbrev_type abbrev() const {
return s_scaled_unit.natural_unit_.abbrev();
}
///@}
/** @defgroup quantity-arithmetic-support **/
///@{
/** create unit quantity with same unit as @c this **/
constexpr
auto unit_qty() const {
return quantity<s_scaled_unit, repr_type>(1);
}
/** create zero quantity with same unit as @c this **/
constexpr
auto zero_qty() const {
return quantity<s_scaled_unit, repr_type>(0);
}
constexpr
auto reciprocal() const {
return quantity<s_scaled_unit.reciprocal(),
repr_type>(1.0 / scale_);
}
///@}
/** @defgroup quantity-unit-conversion **/
///@{
/** create equivalent quantity using scale representation @p Repr2 instead of @c Repr **/
template <typename Repr2>
constexpr
auto with_repr() const {
return quantity<s_scaled_unit, Repr2>(scale_);
}
/** create equivalent quantity expressed as a multiple of @p NaturalUnit2
* instead of @ref s_unit
**/
template <natural_unit<ratio_int_type> NaturalUnit2>
constexpr
auto rescale() const {
/* conversion factor from .unit -> unit2*/
auto rr = detail::su_ratio<ratio_int_type,
ratio_int2x_type>(s_scaled_unit.natural_unit_,
NaturalUnit2);
if (rr.natural_unit_.is_dimensionless()) {
repr_type r_scale = (((rr.outer_scale_sq_ == 1.0)
? 1.0
: ::sqrt(rr.outer_scale_sq_))
* rr.outer_scale_factor_.template convert_to<repr_type>()
* this->scale_);
return quantity<NaturalUnit2, Repr>(r_scale);
} else {
return quantity<NaturalUnit2, Repr>(std::numeric_limits<repr_type>::quiet_NaN());
}
}
/** create equivalent quantity expressed as as multiple of @p ScaledUnit2
* instead of @ref s_unit
**/
template <scaled_unit<ratio_int_type> ScaledUnit2>
constexpr
auto rescale_ext() const {
/* conversion factor from .unit -> unit2*/
auto rr = detail::su_ratio<ratio_int_type,
ratio_int2x_type>(s_scaled_unit.natural_unit_,
ScaledUnit2.natural_unit_);
if (rr.natural_unit_.is_dimensionless()) {
/* NOTE: test for unit .outer_scale_sq values to get constexpr result with c++23
* and integer dimension powers.
*
* NOTE: we don't intend to support mixed-unit quantities.
* If we change intention, will need to take into account
* (s_scaled_unit.outer_scale_factor_, s_scaled_unit.outer_scale_sq_)
*/
repr_type r_scale = ((((rr.outer_scale_sq_ == 1.0)
&& (ScaledUnit2.outer_scale_sq_ == 1.0))
? 1.0
: ::sqrt(rr.outer_scale_sq_ / ScaledUnit2.outer_scale_sq_))
* rr.outer_scale_factor_.template convert_to<repr_type>()
* this->scale_
/ ScaledUnit2.outer_scale_factor_.template convert_to<repr_type>());
return quantity<ScaledUnit2, Repr>(r_scale);
} else {
return quantity<ScaledUnit2, Repr>(std::numeric_limits<repr_type>::quiet_NaN());
}
}
///@}
/** @addtogroup quantity-arithmetic-support **/
///@{
/** create quantity representing this amount multiplied by dimensionless value @p x
*
* @pre x must be an arithmetic type such as @c int or @c double
**/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr auto scale_by(Dimensionless x) const {
using r_repr_type = std::common_type_t<repr_type, Dimensionless>;
return quantity<s_scaled_unit, r_repr_type>(x * this->scale_);
}
/** create quantity representing this quantity divided by dimensionless value @p x
*
* @pre x must be an arithmetic type such as @c int or @c double
**/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr auto divide_by(Dimensionless x) const {
using r_repr_type = std::common_type_t<repr_type, Dimensionless>;
return quantity<s_scaled_unit, r_repr_type>(this->scale_ / x);
}
/** create quantity representing dimensionless value @x divided by this quantity
*
* @pre x must be an arithmetic type such as @c int or @c double
**/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr auto divide_into(Dimensionless x) const {
using r_repr_type = std::common_type_t<repr_type, Dimensionless>;
return quantity(static_cast<r_repr_type>(x) / this->scale_,
s_scaled_unit.reciprocal());
}
///@}
/** @defgroup quantity-comparison-support **/
///@{
/** compare two @c quantity instances, under three-way comparison **/
template <typename Quantity2>
static constexpr
auto compare(const quantity &x, const Quantity2 & y) {
quantity y2 = y.template rescale_ext<s_scaled_unit>();
return x.scale() <=> y2.scale();
}
///@}
/** @defgroup quantity-operators **/
///@{
/** unary negation; preserves unit information **/
quantity operator-() const {
return quantity(-scale_);
}
/** add @p y in-place, converting units if necessary **/
template <typename Quantity2>
constexpr
quantity & operator+=(const Quantity2 & y) {
quantity y2 = y.template rescale_ext<s_scaled_unit>();
this->scale_ += y2.scale();
return *this;
}
/** subtract @p y in-place, converting units if necessary **/
template <typename Quantity2>
constexpr
quantity & operator-=(const Quantity2 & y) {
quantity y2 = y.template rescale_ext<s_scaled_unit>();
this->scale_ -= y2.scale();
return *this;
}
/** multiply @p y in-place. y must be dimensionless **/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr
quantity & operator*=(Dimensionless y) {
this->scale_ *= y;
return *this;
}
/** divide @p y in-place. y must be dimensionless **/
template <typename Dimensionless>
requires std::is_arithmetic_v<Dimensionless>
constexpr
quantity & operator/=(Dimensionless y) {
this->scale_ /= y;
return *this;
}
///@}
/** @defgroup quantity-assignment quantity assignment operators **/
///@{
/** assignment from quantity with identical units **/
quantity & operator=(const quantity & x) {
this->scale_ = x.scale_;
return *this;
}
/** assignment from quantity with compatible units **/
template <typename Q2>
requires(quantity_concept<Q2>
&& Q2::always_constexpr_unit)
quantity & operator=(const Q2 & x) {
auto x2 = x.template rescale_ext<s_scaled_unit>();
this->scale_ = x2.scale();
return *this;
}
///@}
/** @defgroup quantity-unit-conversion **/
///@{
/** */
template <typename Q2>
requires(quantity_concept<Q2>
&& Q2::always_constexpr_unit)
constexpr operator Q2() const {
return this->template rescale_ext<Q2::s_scaled_unit>().template with_repr<typename Q2::repr_type>();
}
/** For dimensionless quantities: convert to underlying scale value
*
* Not present for dimensioned quantities.
**/
constexpr operator Repr() const
requires (ScaledUnit.is_dimensionless())
{
return scale_;
}
///@}
public: /* need public members so that instance can be a non-type template parameter (is a structural type) */
/** @defgroup quantity-static-vars **/
///@{
/** @brief unit for quantity of this type. Determined at compile-time **/
static constexpr scaled_unit<ratio_int_type> s_scaled_unit = ScaledUnit;
///@}
/** @defgroup quantity-instance-vars **/
///@{
/** quantity represents this multiple of @ref s_scaled_unit
*
* Public to avoid disqualifying @c quantity as a 'structural type';
* prerequisite for using a @c quantity instance as a non-type template parameter
**/
Repr scale_ = Repr{};
///@}
};
///@{
/**
*
**/
template <typename Quantity, typename Int, typename Int2x>
constexpr auto
rescale(const Quantity & x,
const scaled_unit<Int, Int2x> & su) {
return x.template rescale<su>();
}
///@}
namespace detail {
struct quantity_util {
/* parallel implementation to xquantity<Repr, Int> multiply,
* but return type will have dimension computed at compile-time
*/
template <typename Q1, typename Q2>
requires (quantity_concept<Q1>
&& quantity_concept<Q2>
&& Q1::always_constexpr_unit
&& Q2::always_constexpr_unit)
static constexpr auto multiply(Q1 x, Q2 y) {
using r_repr_type = std::common_type_t<typename Q1::repr_type,
typename Q2::repr_type>;
using r_int_type = std::common_type_t<typename Q1::ratio_int_type,
typename Q2::ratio_int_type>;
using r_int2x_type = std::common_type_t<typename Q1::ratio_int2x_type,
typename Q2::ratio_int2x_type>;
constexpr auto rr = detail::su_product<r_int_type, r_int2x_type>(x.unit().natural_unit_,
y.unit().natural_unit_);
r_repr_type r_scale = (((rr.outer_scale_sq_ == 1.0)
? 1.0
: ::sqrt(rr.outer_scale_sq_))
* rr.outer_scale_factor_.template convert_to<r_repr_type>()
* static_cast<r_repr_type>(x.scale())
* static_cast<r_repr_type>(y.scale()));
return quantity<detail::su_promote<r_int_type>(rr.natural_unit_),
r_repr_type>(r_scale);
}
template <typename Q1, typename Q2>
requires (quantity_concept<Q1>
&& quantity_concept<Q2>
&& Q1::always_constexpr_unit
&& Q2::always_constexpr_unit)
static constexpr auto divide(Q1 x, Q2 y) {
using r_repr_type = std::common_type_t<typename Q1::repr_type,
typename Q2::repr_type>;
using r_int_type = std::common_type_t<typename Q1::ratio_int_type,
typename Q2::ratio_int_type>;
using r_int2x_type = std::common_type_t<typename Q1::ratio_int2x_type,
typename Q2::ratio_int2x_type>;
constexpr auto rr = detail::su_ratio<r_int_type, r_int2x_type>(x.unit().natural_unit_,
y.unit().natural_unit_);
r_repr_type r_scale = (((rr.outer_scale_sq_ == 1.0)
? 1.0
: ::sqrt(rr.outer_scale_sq_))
* rr.outer_scale_factor_.template convert_to<r_repr_type>()
* static_cast<r_repr_type>(x.scale())
/ static_cast<r_repr_type>(y.scale()));
return quantity<detail::su_promote<r_int_type>(rr.natural_unit_),
r_repr_type>(r_scale);
}
template <typename Q1, typename Q2>
requires(quantity_concept<Q1>
&& quantity_concept<Q2>
&& Q1::always_constexpr_unit
&& Q2::always_constexpr_unit)
static constexpr auto add(Q1 x, Q2 y) {
using r_repr_type = std::common_type_t<typename Q1::repr_type,
typename Q2::repr_type>;
using r_int_type = std::common_type_t<typename Q1::ratio_int_type,
typename Q2::ratio_int_type>;
using r_int2x_type = std::common_type_t<typename Q1::ratio_int2x_type,
typename Q2::ratio_int2x_type>;
/* conversion to get y in same units as x: multiply by y/x */
auto rr = detail::su_ratio<r_int_type, r_int2x_type>(y.unit().natural_unit_,
x.unit().natural_unit_);
if (rr.natural_unit_.is_dimensionless()) {
r_repr_type r_scale = (static_cast<r_repr_type>(x.scale())
+ (::sqrt(rr.outer_scale_sq_)
* rr.outer_scale_factor_.template convert_to<r_repr_type>()
* static_cast<r_repr_type>(y.scale())));
return quantity<x.s_scaled_unit, r_repr_type>(r_scale);
} else {
/* units don't match! */
return quantity<x.s_scaled_unit, r_repr_type>(std::numeric_limits<r_repr_type>::quiet_NaN());
}
}
template <typename Q1, typename Q2>
requires(quantity_concept<Q1>
&& quantity_concept<Q2>
&& Q1::always_constexpr_unit
&& Q2::always_constexpr_unit)
static constexpr auto subtract(Q1 x, Q2 y) {
using r_repr_type = std::common_type_t<typename Q1::repr_type,
typename Q2::repr_type>;
using r_int_type = std::common_type_t<typename Q1::ratio_int_type,
typename Q2::ratio_int_type>;
using r_int2x_type = std::common_type_t<typename Q1::ratio_int2x_type,
typename Q2::ratio_int2x_type>;
/* conversion to get y in same units as x: multiply by y/x */
auto rr = detail::su_ratio<r_int_type, r_int2x_type>(y.unit(), x.unit());
if (rr.natural_unit_.is_dimensionless()) {
r_repr_type r_scale = (static_cast<r_repr_type>(x.scale())
- (::sqrt(rr.outer_scale_sq_)
* rr.outer_scale_factor_.template convert_to<r_repr_type>()
* static_cast<r_repr_type>(y.scale())));
return quantity<x.s_unit, r_repr_type>(r_scale);
} else {
/* units don't match! */
return quantity<x.s_unit, r_repr_type>(std::numeric_limits<r_repr_type>::quiet_NaN());
}
}
};
} /*namespace detail*/
template <auto Unit, typename Q1>
requires(quantity_concept<Q1>
&& Q1::always_constexpr_unit)
constexpr auto
with_units(const Q1 & x) {
return x.template rescale_ext<Unit>();
}
template <typename Q1, typename Q2, auto Unit = Q2::s_scaled_unit>
requires (quantity_concept<Q1>
&& quantity_concept<Q2>
&& Q1::always_constexpr_unit
&& Q2::always_constexpr_unit)
constexpr auto
with_units_from(const Q1 & x, const Q2 & y)
{
return x.template rescale_ext<Unit>();
}
template <typename Repr2, typename Q1>
requires (quantity_concept<Q1>
&& Q1::always_constexpr_unit)
constexpr auto
with_repr(const Q1 & x)
{
return x.template with_repr<Repr2>();
}
/** @addtogroup quantity-operators **/
///@{
/** note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
**/
template <typename Q1, typename Q2>
requires (quantity_concept<Q1>
&& quantity_concept<Q2>
&& Q1::always_constexpr_unit
&& Q2::always_constexpr_unit)
constexpr auto
operator* (const Q1 & x, const Q2 & y)
{
return detail::quantity_util::multiply(x, y);
}
/** note: does not require unit scaling, so constexpr with c++23 **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
constexpr auto
operator* (const Quantity & x, Dimensionless y)
{
return x.scale_by(y);
}
/** note: does not require unit scaling, so constexpr with c++23 **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
constexpr auto
operator* (Dimensionless x, const Quantity & y)
{
return y.scale_by(x);
}
/** divide quantity @p x by quantity @p y.
*
* note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
**/
template <typename Q1, typename Q2>
requires (quantity_concept<Q1>
&& quantity_concept<Q2>
&& Q1::always_constexpr_unit
&& Q2::always_constexpr_unit)
constexpr auto
operator/ (const Q1 & x, const Q2 & y)
{
return detail::quantity_util::divide(x, y);
}
/** divide quantity @p x by dimensionless value @p y **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
constexpr auto
operator/ (const Quantity & x, Dimensionless y)
{
return x.divide_by(y);
}
/** divide dimensionless value @p x by quantity @p y **/
template <typename Dimensionless, typename Quantity>
requires std::is_arithmetic_v<Dimensionless> && quantity_concept<Quantity>
constexpr auto
operator/ (Dimensionless x, const Quantity & y)
{
return y.divide_into(x);
}
/** add quantity @p y to quantity @p x. Result will have the same units as @p x.
* Representation will be the widest of {@c x::repr_type, @c y::repr_type}.
*
* note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
*
* @pre @p x and @p y expected to have consistent dimensions
**/
template <typename Q1, typename Q2>
requires (quantity_concept<Q1>
&& quantity_concept<Q2>
&& Q1::always_constexpr_unit
&& Q2::always_constexpr_unit)
constexpr auto
operator+ (const Q1 & x, const Q2 & y)
{
return detail::quantity_util::add(x, y);
}
/** subtract an arithmetic value from a dimensionless quantity **/
template <typename Quantity,
typename Dimensionless>
requires (quantity_concept<Quantity>
&& Quantity::is_dimensionless()
&& std::is_arithmetic_v<Dimensionless>)
constexpr auto
operator+ (const Quantity & x, Dimensionless y)
{
using repr_type = std::common_type_t<typename Quantity::repr_type, Dimensionless>;
auto xp = static_cast<repr_type>(x.scale());
auto yp = static_cast<repr_type>(y);
return xp + yp;
}
/** subtract a dimensionless quantity from an arithmetic value **/
template <typename Dimensionless,
typename Quantity>
requires (std::is_arithmetic_v<Dimensionless>
&& quantity_concept<Quantity>
&& Quantity::is_dimensionless())
constexpr auto
operator+ (Dimensionless x, const Quantity & y)
{
using repr_type = std::common_type_t<Dimensionless, typename Quantity::repr_type>;
auto xp = static_cast<repr_type>(x);
auto yp = static_cast<repr_type>(y.scale());
return xp + yp;
}
/** subtract quantity @p y from quantity @p x. Result will have the same units as @p x.
* Representation will be the widest of {@c x::repr_type, @c y::repr_type}
*
* note: won't have constexpr result w/ fractional dimension until c++26 (when ::sqrt(), ::pow() are constexpr)
*
* @pre @p x and @p y expected to have consistent dimensions
**/
template <typename Q1, typename Q2>
requires (quantity_concept<Q1>
&& quantity_concept<Q2>
&& Q1::always_constexpr_unit
&& Q2::always_constexpr_unit)
constexpr auto
operator- (const Q1 & x, const Q2 & y)
{
return detail::quantity_util::subtract(x, y);
}
/** subtract an arithmetic value from a dimensionless quantity **/
template <typename Quantity,
typename Dimensionless>
requires (quantity_concept<Quantity>
&& Quantity::is_dimensionless()
&& std::is_arithmetic_v<Dimensionless>)
constexpr auto
operator- (const Quantity & x, Dimensionless y)
{
using repr_type = std::common_type_t<typename Quantity::repr_type, Dimensionless>;
auto xp = static_cast<repr_type>(x.scale());
auto yp = static_cast<repr_type>(y);
return xp - yp;
}
/** subtract a dimensionless quantity from an arithmetic value **/
template <typename Dimensionless,
typename Quantity>
requires (std::is_arithmetic_v<Dimensionless>
&& quantity_concept<Quantity>
&& Quantity::is_dimensionless())
constexpr auto
operator- (Dimensionless x, const Quantity & y)
{
using repr_type = std::common_type_t<Dimensionless, typename Quantity::repr_type>;
auto xp = static_cast<repr_type>(x);
auto yp = static_cast<repr_type>(y.scale());
return xp - yp;
}
///@}
namespace qty {
// ----- mass -----
/** create quantity representing @p x picograms of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto picograms(Repr x) { return quantity<u::picogram, Repr>(x); }
/** create quantity representing @p x nanograms of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto nanograms(Repr x) { return quantity<u::nanogram, Repr>(x); }
/** create quantity representing @p x micrograms of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto micrograms(Repr x) { return quantity<u::microgram, Repr>(x); }
/** create quantity representing @p x milligrams of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto milligrams(Repr x) { return quantity<u::milligram, Repr>(x); }
/** create quantity representing @p x grams of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto grams(Repr x) { return quantity<u::gram, Repr>(x); }
/** create quantity representing @p x kilograms of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto kilograms(Repr x) { return quantity<u::kilogram, Repr>(x); }
/** create quantity representing @p x tonnes of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto tonnes(Repr x) { return quantity<u::tonne, Repr>(x); }
/** create quantity representing @p x kilotonnes of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto kilotonnes(Repr x) { return quantity<u::kilotonne, Repr>(x); }
/** create quantity representing @p x megatonnes of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto megatonnes(Repr x) { return quantity<u::megatonne, Repr>(x); }
/** create quantity representing @p x gigatonnes of mass, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto gigatonnes(Repr x) { return quantity<u::gigatonne, Repr>(x); }
}
namespace qty {
// ----- mass constants ----
/** a quantity representing 1 picogram of mass, with compile-time unit representation **/
static constexpr auto picogram = picograms(1);
/** a quantity representing 1 nanogram of mass, with compile-time unit representation **/
static constexpr auto nanogram = nanograms(1);
/** a quantity representing 1 microgram of mass, with compile-time unit representation **/
static constexpr auto microgram = micrograms(1);
/** a quantity representing 1 milligram of mass, with compile-time unit representation **/
static constexpr auto milligram = milligrams(1);
/** a quantity representing 1 gram of mass, with compile-time unit representation **/
static constexpr auto gram = grams(1);
/** a quantity representing 1 kilogram of mass, with compile-time unit representation **/
static constexpr auto kilogram = kilograms(1);
/** a quantity representing 1 metric tonne of mass, with compile-time unit representation **/
static constexpr auto tonne = tonnes(1);
/** a quantity representing 1 metric kilotonne of mass, with compile-time unit representation **/
static constexpr auto kilotonne = kilotonnes(1);
/** a quantity representing 1 metric megatonne of mass, with compile-time unit representation **/
static constexpr auto megatonne = megatonnes(1);
/** a quantity representing 1 metric gigatonne of mass, with compile-time unit representation **/
static constexpr auto gigatonne = gigatonnes(1);
} /*namespace qty*/
namespace qty {
// ----- distance -----
/** create quantity representing @p x picometers of distance, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto picometers(Repr x) { return quantity<u::picometer, Repr>(x); }
/** create quantity representing @p x nanometers of distance, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto nanometers(Repr x) { return quantity<u::nanometer, Repr>(x); }
/** create quantity representing @p x micrometers of distance, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto micrometers(Repr x) { return quantity<u::micrometer, Repr>(x); }
/** create quantity representing @p x millimeters of distance, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto millimeters(Repr x) { return quantity<u::millimeter, Repr>(x); }
/** create quantity representing @p x meters of distance, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto meters(Repr x) { return quantity<u::meter, Repr>(x); }
/** create quantity representing @p x kilometers of distance, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto kilometers(Repr x) { return quantity<u::kilometer, Repr>(x); }
/** create quantity representing @p x megameters of distance, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto megameters(Repr x) { return quantity<u::megameter, Repr>(x); }
/** create quantity representing @p x gigameters of distance,
* with compile-time unit operations
**/
template <typename Repr>
inline constexpr auto gigameters(Repr x) { return quantity<u::gigameter, Repr>(x); }
/** create quantity representing @p x light-seconds of distance,
* with compile-time unit operations.
**/
template <typename Repr>
inline constexpr auto lightseconds(Repr x) { return quantity<u::lightsecond, Repr>(x); }
/** create quantity representing @p x astronomical units of distance,
* with compile-time unit representation
**/
template <typename Repr>
inline constexpr auto astronomicalunits(Repr x) { return quantity<u::astronomicalunit, Repr>(x); }
/** create quantity representing @p x inches of distance, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto inches(Repr x) { return quantity<u::inch, Repr>(x); }
/** create quantity representing @p x feet of distance, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto feet(Repr x) { return quantity<u::foot, Repr>(x); }
/** create quantity representing @p x yards of distance, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto yards(Repr x) { return quantity<u::yard, Repr>(x); }
/** create quantity representing @p x statute miles of distance, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto miles(Repr x) { return quantity<u::mile, Repr>(x); }
}
namespace qty {
// ----- distance constants -----
/** a quantity representing 1 picometer of distance, with compile-time unit representation **/
static constexpr auto picometer = picometers(1);
/** a quantity representing 1 nanometer of distance, with compile-time unit representation **/
static constexpr auto nanometer = nanometers(1);
/** a quantity representing 1 micrometer of distance, with compile-time unit representation **/
static constexpr auto micrometer = micrometers(1);
/** a quantity representing 1 millimeter of distance, with compile-time unit representation **/
static constexpr auto millimeter = millimeters(1);
/** a quantity representing 1 meter of distance, with compile-time unit representation **/
static constexpr auto meter = meters(1);
/** a quantity representing 1 kilometer of distance, with compile-time unit representation **/
static constexpr auto kilometer = kilometers(1);
/** a quantity representing 1 megameter of distance, with compile-time unit representation **/
static constexpr auto megameter = megameters(1);
/** a quantity representing 1 gigameter of distance, with compile-time unit representation **/
static constexpr auto gigameter = gigameters(1);
/** a quantity representing exactly 1 lightsecond of distance,
* with compile-time unit representation
**/
static constexpr auto lightsecond = lightseconds(1);
/** a quantity representing exactly 1 astronomical unit of distance,
* with compile-time unit representation
**/
static constexpr auto astronomicalunit = astronomicalunits(1);
/** a quantity representing 1 inch of distance, with compile-time unit operations **/
static constexpr auto inch = inches(1);
/** a quantity representing 1 foot of distance, with compile-time unit operations **/
static constexpr auto foot = feet(1);
/** a quantity representing 1 yard of distance, with compile-time unit operations **/
static constexpr auto yard = yards(1);
/** a quantity representing 1 mile of distance, with compile-time unit operations **/
static constexpr auto mile = miles(1);
} /*namespace qty*/
namespace qty {
// ----- time -----
/** create quantity representing @p x picoseconds of time, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto picoseconds(Repr x) { return quantity<u::picosecond, Repr>(x); }
/** create quantity representing @p x nanoseconds of time, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto nanoseconds(Repr x) { return quantity<u::nanosecond, Repr>(x); }
/** create quantity representing @p x microseconds of time, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto microseconds(Repr x) { return quantity<u::microsecond, Repr>(x); }
/** create quantity representing @p x milliseconds of time, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto milliseconds(Repr x) { return quantity<u::millisecond, Repr>(x); }
/** create quantity representing @p x seconds of time, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto seconds(Repr x) { return quantity<u::second, Repr>(x); }
/** create quantity representing @p x minutes of time, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto minutes(Repr x) { return quantity<u::minute, Repr>(x); }
/** create quantity representing @p x hours of time, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto hours(Repr x) { return quantity<u::hour, Repr>(x); }
/** create quantity representing @p x exactly-24-hour days of time, with compile-time unit operations **/
template <typename Repr>
inline constexpr auto days(Repr x) { return quantity<u::day, Repr>(x); }
/** creeate quantity representing @p x weeks of time,
* with compile-time unit operations. Each week has exactly 7 24-hour days.
**/
template <typename Repr>
inline constexpr auto weeks(Repr x) { return quantity<u::week, Repr>(x); }
/** create quantity representing @p x months of time,
* with compile-time unit operations. Each month has exactly 30 24-hour days
**/
template <typename Repr>
inline constexpr auto months(Repr x) { return quantity<u::month, Repr>(x); }
/** create quantity representing @p x years of time,
* with compile-time unit operations. Each year has exactly 365.25 24-hour days
**/
template <typename Repr>
inline constexpr auto years(Repr x) { return quantity<u::year, Repr>(x); }
/** create quantity representing @p x '250-day years' of time.
* 250 represents approximate number of business days in a calendar year.
**/
template <typename Repr>
inline constexpr auto year250s(Repr x) { return quantity<u::year250, Repr>(x); }
/** create quantity representing @p x '360-day years' of time **/
template <typename Repr>
inline constexpr auto year360s(Repr x) { return quantity<u::year360, Repr>(x); }
/** create quantity representing @p x '365-day years' of time **/
template <typename Repr>
inline constexpr auto year365s(Repr x) { return quantity<u::year365, Repr>(x); }
}
namespace qty {
// ----- time constants ----
/** a quantity representing 1 picosecond of time, with compile-time unit representation **/
static constexpr auto picosecond = picoseconds(1);
/** a quantity representing 1 nanosecond of time, with compile-time unit representation **/
static constexpr auto nanosecond = nanoseconds(1);
/** a quantity representing 1 microsecond of time, with compile-time unit representation **/
static constexpr auto microsecond = microseconds(1);
/** a quantity representing 1 millisecond of time, with compile-time unit representation **/
static constexpr auto millisecond = milliseconds(1);
/** a quantity representing 1 second of time, with compile-time unit representation **/
static constexpr auto second = seconds(1);
/** a quantity representing 1 minute of time, with compile-time unit representation **/
static constexpr auto minute = minutes(1);
/** a quantity representing 1 hour of time, with compile-time unit representation **/
static constexpr auto hour = hours(1);
/** a quantity representing 1 day of time (exactly 24 hours), with compile-time unit representation **/
static constexpr auto day = days(1);
/** a quantity representing 1 week of time (7 24-hour days), with compile-time unit representation **/
static constexpr auto week = weeks(1);
/** a quantity representing 1 month of time (30 24-hour days), with compile-time unit representation **/
static constexpr auto month = months(1);
/** a quantity representing 1 year of time (365.25 24-hour days), with compile-time unit representation **/
static constexpr auto year = years(1);
/** a quantity representing 1 250-day year of time, with compile-time unit representation **/
static constexpr auto year250 = year250s(1);
/** a quantity representing 1 360-day year of time, with compile-time unit representation **/
static constexpr auto year360 = year360s(1);
/** a quantity representing 1 365-day year of time, with compile-time unit representation **/
static constexpr auto year365 = year365s(1);
} /*namespace qty*/
namespace qty {
// ----- volatility -----
/* variance expressed has dimension 1/t;
* volatility ~ sqrt(variance), has dimension 1/sqrt(t)
*/
/** create quantity representing @p x units of 30-day volatility, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto volatility_30d(Repr x) { return quantity<u::volatility_30d, Repr>(x); }
/** create quantity representing @p x units of 250-day volatility, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto volatility_250d(Repr x) { return quantity<u::volatility_250d, Repr>(x); }
/** create quantity representing @p x units of 360-day volatility, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto volatility_360d(Repr x) { return quantity<u::volatility_360d, Repr>(x); }
/** create quantity representing @p x units of 365-day volatility, with compile-time unit representation **/
template <typename Repr>
inline constexpr auto volatility_365d(Repr x) { return quantity<u::volatility_365d, Repr>(x); }
} /*namespace qty*/
/* reminder: see [quantity_ops.hpp] for operator* etc */
} /*namespace qty*/
} /*namespace xo*/
/** end quantity.hpp **/