Class Ifc4x2::IfcConversionBasedUnit

Nested Relationships

This class is a nested type of Struct Ifc4x2.

Inheritance Relationships

Base Type

Derived Type

Class Documentation

class Ifc4x2::IfcConversionBasedUnit : public Ifc4x2::IfcNamedUnit

Definition from ISO/CD 10303-41:1992: A conversion based unit is a unit that is defined based on a measure with unit.

NOTE Corresponding ISO 10303 name: conversion_based_unit, please refer to ISO/IS 10303-41 for the final definition of the formal standard.

HISTORY New entity in IFC Release 1.5.1.

IFC 2x3 change: standard names of typical units added.

IFC 2x4 change: further names added: square inch, square foot, square mile, square yard, cubic inch, cubic foot, cubic yard, fluid ounce UK/US, ton UK/US, degree.

Example: An inch is a converted unit. It is from the Imperial system, its name is “inch” and it can be related to the si unit, millimetre, through a measure with unit whose value is 25.4 millimetre. A foot is also a converted unit. It is from the Imperial system, its name is “foot” and it can be related to an IfcSIUnit, millimetre, either directly or through the unit called “inch”. Note that several US customary units differ from Imperial units (nonmetric English units) of the same name.

To identify some commonly used conversion based units, the standard designations (case insensitive) for the Name attribute include the following:

Name Description ‘inch’ Length measure equal to 25.4 mm ‘foot’ Length measure equal to 304.8 mm ‘yard’ Length measure equal to 914 mm ‘mile’ Length measure equal to 1609 m ‘square inch’ Area measure equal to 0.0006452 square meters ‘square foot’ Area measure equal to 0.09290 square meters ‘square yard’ Area measure equal to 0.83612736 square meters ‘acre’ Area measure equal to 4046.86 square meters ‘square mile’ Area measure equal to 2 588 881 square meters ‘cubic inch’ Volume measure equal to 0.00001639 cubic meters ‘cubic foot’ Volume measure equal to 0.02832 cubic meters ‘cubic yard’ Volume measure equal to 0.7636 cubic meters ‘litre’ Volume measure equal to 0.001 cubic meters ‘fluid ounce UK’ Volume measure equal to 0.0000284130625 cubic meters ‘fluid ounce US’ Volume measure equal to 0.00002957353 cubic meters ‘pint UK’ Volume measure equal to 0.000568 cubic meters ‘pint US’ Volume measure equal to 0.000473 cubic meters ‘gallon UK’ Volume measure equal to 0.004546 cubic meters ‘gallon US’ Volume measure equal to 0.003785 cubic meters ‘degree’ Angle measure equal to π/180 rad ‘ounce’ Mass measure equal to 28.35 g ‘pound’ Mass measure equal to 0.454 kg ‘ton UK’ Mass measure equal to 1016.0469088 kg, also known as long ton, gross ton, shipper’s ton ‘ton US’ Mass measure equal to 907.18474 kg, also known as short ton, net ton ‘lbf’ Force measure equal to 4.4482216153 N, pound-force ‘kip’ Force measure equal to 4448.2216153 N, kilopound-force ‘psi’ Pressure measure equal to 6894.7572932 Pa, pound-force per square inch ‘ksi’ Pressure measure equal to 6894757.2932 Pa, kilopound-force per square inch ‘minute’ Time measure equal to 60 s ‘hour’ Time measure equal to 3600 s ‘day’ Time measure equal to 86400 s ‘btu’ Energy measure equal to 1055.056 J, British Thermal Unit

Subclassed by Ifc4x2::IfcConversionBasedUnitWithOffset

Public Types

typedef IfcTemplatedEntityList<IfcConversionBasedUnit> list

Public Functions

std::string Name() const

The word, or group of words, by which the conversion based unit is referred to.

void setName(std::string v)
::Ifc4x2::IfcMeasureWithUnit *ConversionFactor() const

The physical quantity from which the converted unit is derived.

void setConversionFactor(::Ifc4x2::IfcMeasureWithUnit *v)
IfcTemplatedEntityList<IfcExternalReferenceRelationship>::ptr HasExternalReference() const
const IfcParse::entity &declaration() const
IfcConversionBasedUnit(IfcEntityInstanceData *e)
IfcConversionBasedUnit(::Ifc4x2::IfcDimensionalExponents *v1_Dimensions, ::Ifc4x2::IfcUnitEnum::Value v2_UnitType, std::string v3_Name, ::Ifc4x2::IfcMeasureWithUnit *v4_ConversionFactor)

Public Static Functions

const IfcParse::entity &Class()