emlabcpp::physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte > Struct Template Reference

physical_quantity represents all physical units defined using the International System of Units and more. More...

#include <physical_quantity.h>

Inheritance diagram for emlabcpp::physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >:

Collaboration diagram for emlabcpp::physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >:

Static Public Member Functions
template<int Exp, char... Unit>
static consteval auto	get_single_unit ()
static std::string_view	get_unit ()
Static Public Member Functions inherited from emlabcpp::quantity< physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >, float >
static std::string	get_unit ()

Static Public Attributes
template<int Exp, char... Unit>
static constexpr std::array	single_unit = get_single_unit< Exp, Unit... >()
static constexpr std::array	unit

Additional Inherited Members
Public Types inherited from emlabcpp::quantity< physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >, float >
using	value_type = float
Public Member Functions inherited from emlabcpp::quantity< physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >, float >
constexpr	quantity () noexcept
constexpr	quantity (Value val) noexcept
	Default constructor used to create a physical quantity from value. More...
constexpr float	operator* () const noexcept
	Const reference to the internal value. More...
constexpr physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte > &	operator+= (quantity const other) noexcept
	Add other quantity of same Derived and value_type. More...
constexpr physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte > &	operator-= (quantity const other) noexcept
	Subtract other quantity of same Derived and value_type. More...
constexpr physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte > &	operator/= (arithmetic auto const val) noexcept
	Divides quantity by it's value type. More...
constexpr physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte > &	operator*= (arithmetic auto const val) noexcept
	Multiplies quantity by it's value type. More...
constexpr	operator U () const noexcept
	Provides explicit conversion of internal value to type U. More...

Detailed Description

template<int Len, int Mass, int Time, int Current, int Temp, int Mol, int Li, int Angle, int Byte>
struct emlabcpp::physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >

physical_quantity represents all physical units defined using the International System of Units and more.

The idea is that each used unit, is either one of the seven basic units, or defined as some combination of them. The combination is multiplication of exponents of basic units.

So, velocity is distance per time - m*s^-1.

We defined each physical unit by using a template, that has exponent of each basic unit as exponent. This makes it possible to specify any unit using this class - as combination of basic units.

We expand this by providing two additional 'basic' units - angle (which is handy for us) and byte.

Given that we have the exponents of basic units as integers in the type, we can write generic multiplication and division between all possible templates.

This trick is inspired by the haskell's dimensional library which does the same.

Member Function Documentation

get_single_unit()

template<int Len, int Mass, int Time, int Current, int Temp, int Mol, int Li, int Angle, int Byte>

template<int Exp, char... Unit>

static consteval auto emlabcpp::physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >::get_single_unit ( )

inlinestatic

get_unit()

template<int Len, int Mass, int Time, int Current, int Temp, int Mol, int Li, int Angle, int Byte>

static std::string_view emlabcpp::physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >::get_unit ( )

inlinestatic

References emlabcpp::physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >::unit.

Member Data Documentation

single_unit

template<int Len, int Mass, int Time, int Current, int Temp, int Mol, int Li, int Angle, int Byte>

template<int Exp, char... Unit>

constexpr std::array emlabcpp::physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >::single_unit = get_single_unit< Exp, Unit... >()

staticconstexpr

unit

template<int Len, int Mass, int Time, int Current, int Temp, int Mol, int Li, int Angle, int Byte>

constexpr std::array emlabcpp::physical_quantity< Len, Mass, Time, Current, Temp, Mol, Li, Angle, Byte >::unit

staticconstexpr

Initial value:

= merge_arrays(
            single_unit< Len, 'm' >,
            single_unit< Mass, 'k', 'g' >,
            single_unit< Time, 's' >,
            single_unit< Current, 'A' >,
            single_unit< Temp, 'K' >,
            single_unit< Mol, 'm', 'o', 'l' >,
            single_unit< Li, 'c', 'd' >,
            single_unit< Angle, 'r', 'a', 'd' >,
            single_unit< Byte, 'B' > )

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

• include/emlabcpp/physical_quantity.h