A constant defined in terms of a unit
Declared in <mp-units/framework/unit_definitions.h>
template<
symbol_text Symbol,
Unit auto U,
auto...>
struct named_constant;Similarly to named_unit, associates a symbol with a unit, but represents a specific measured or exact value (e.g. si::si2019::speed_of_light_in_vacuum) rather than a unit of measurement.
| Name | Description |
|---|---|
named_constant<Symbol, U> | Named constant definition |
named_constant<Symbol, U, RSU> | Specialization for a measured constant declaring its relative standard uncertainty |
named_constant<Symbol, U, SU> | Specialization for a measured constant declaring its absolute standard uncertainty |
| Name | Description |
|---|---|
pi | The mathematical constant π, exposed as a dimensionless named constant |
| Name | Description |
|---|---|
| Symbol | a short text representation of the constant |
| U | a unit that we use to define a constant |