Public Types

typedef units::traits::unit_traits< BaseUnit >::base_unit_type base_unit_type
typedef std::ratio_multiply< typename BaseUnit::conversion_ratio, Conversion > conversion_ratio
typedef std::ratio_add< typename BaseUnit::pi_exponent_ratio, PiExponent > pi_exponent_ratio
typedef std::ratio_add< std::ratio_multiply< typename BaseUnit::conversion_ratio, Translation >, typename BaseUnit::translation_ratio > translation_ratio

template<class Conversion, class BaseUnit, class PiExponent = std::ratio<0>, class Translation = std::ratio<0>>

struct units::unit< Conversion, BaseUnit, PiExponent, Translation >"Type representing an arbitrary unit.

unit types are used as tags for the conversion function. They are not containers (see unit_t for a container class). Each unit is defined by:

• A std::ratio defining the conversion factor to the base unit type. (e.g. std::ratio<1,12> for inches to feet)
• A base unit that the unit is derived from (or a unit category. Must be of type unit or base_unit)
• An exponent representing factors of PI required by the conversion. (e.g. std::ratio<-1> for a radians to degrees conversion)
• a ratio representing a datum translation required for the conversion (e.g. std::ratio<32> for a fahrenheit to celsius conversion)

Typically, a specific unit, like meters, would be implemented as a type alias of unit, i.e. using meters = unit<std::ratio<1>, units::category::length_unit, or using inches = unit<std::ratio<1,12>, feet>.

Template Parameters