IfcDimensionalExponents

IfcDimensionalExponents

The dimensionality of any quantity can be expressed as a product of powers of the dimensions of base quantities. The dimensional exponents entity defines the powers of the dimensions of the base quantities. All the physical quantities are founded on seven base quantities (ISO 31 (clause 2)).

NOTE: Length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity are the seven base quantities.

EXAMPLE: A length of 2 millimetres has a length exponent of 1. The remaining exponents are equal to 0.

EXAMPLE: A velocity of 2 millimetres per second has a length exponent of 1 and a time exponent of -1. The remaining exponents are equal to 0.

EXPRESS specification:

ENTITY IfcDimensionalExponents;

LengthExponent

INTEGER;

MassExponent

INTEGER;

TimeExponent

INTEGER;

ElectricCurrentExponent

INTEGER;

ThermodynamicTemperatureExponent

INTEGER;

AmountOfSubstanceExponent

INTEGER;

LuminousIntensityExponent

INTEGER;

END_ENTITY;

Attribute definitions:

LengthExponent	:	The power of the length base quantity.
MassExponent	:	The power of the mass base quantity.
TimeExponent	:	The power of the time base quantity.
ElectricCurrentExponent	:	The power of the electric current base quantity.
ThermodynamicTemperatureExponent	:	The power of the thermodynamic temperature base quantity.
AmountOfSubstanceExponent	:	The power of the amount of substance base quantity.
LuminousIntensityExponent	:	The power of the luminous intensity base quantity.