#### 8.14.3.9 IfcPropertyTableValue

| Propriété à valeurs tabulaires
| Merkmal mit Tabellenwert

IfcPropertyTableValue is a property with a value range defined by a property object which has two lists of (numeric or descriptive) values assigned. The values specify a table with two columns. The defining values provide the first column and establish the scope for the defined values (the second column). An optional Expression attribute may give the equation used for deriving the range value, which is for information purposes only.

The IfcPropertyTableValue defines a defining/defined property value combination for which the property name, the table with defining and defined values with measure type (and optional the units for defining and defined values) are given.

> NOTE The IfcPropertyTableValue only captures properties that can be expressed by a table with two columns. Use IfcPropertyReferenceValue with the PropertyReference being an IfcTable to express all those properties that require a table with tree or more columns.

The units are handled by the DefiningUnit and DefinedUnit attributes, see Table 187 for an example of a table value property:

- If the DefiningUnit or DefinedUnit attribute is not given, then the unit is already implied by the type of IfcMeasureValue or IfcDerivedMeasureValue. The associated unit can be found at the IfcUnitAssignment globally defined at the project level (IfcProject.UnitsInContext).
- If the DefiningUnit or DefinedUnit attribute is given, then the unit assigned by the unit attribute overrides the globally assigned unit.

The IfcPropertyTableValue allows for the specification of a table of defining/defined value pairs of the property description. The optional attribute CurveInterpolation allows to determine the interval between two given values.

Name | DefiningValues | DefiningValue Type (through IfcValue) | DefinedValues | DefinedValue Type (through IfcValue) | DefingUnit | DefinedUnit
--- | --- | --- | --- | --- | --- | ---
SoundTransmissionLoss | 100 | IfcFrequencyMeasure | 20 | IfcNumericMeasure | - | dB
| 200 | IfcFrequencyMeasure | 42 | IfcNumericMeasure |  |
| 400 | IfcFrequencyMeasure | 46 | IfcNumericMeasure |  |
| 800 | IfcFrequencyMeasure | 56 | IfcNumericMeasure |  |
| 1600 | IfcFrequencyMeasure | 60 | IfcNumericMeasure |  |
| 3200 | IfcFrequencyMeasure | 65 | IfcNumericMeasure |  |
Table 187 — Table value property with values, measure types and units

> HISTORY New entity in IFC2x.

> IFC4 CHANGE Attributes DefiningValues and DefinedValues have been made OPTIONAL with upward compatibility for file based exchange. The attribute CurveInterpolation has been added.

Informal Propositions:

1. The list of DefinedValues and the list of DefiningValues are corresponding lists.

XSD Specification:

<xs:element name="IfcPropertyTableValue" type="ifc:IfcPropertyTableValue" substitutionGroup="ifc:IfcSimpleProperty" nillable="true"/>
<xs:complexType name="IfcPropertyTableValue">
<xs:complexContent>
<xs:extension base="ifc:IfcSimpleProperty"/>
</xs:complexContent>
</xs:complexType>

EXPRESS Specification:

ENTITY IfcPropertyTableValue

| SUBTYPE OF (IfcSimpleProperty);

DefiningValues | : | OPTIONAL LIST [1:?] OF UNIQUE IfcStrippedOptional;
DefinedValues | : | OPTIONAL LIST [1:?] OF IfcStrippedOptional;
Expression | : | OPTIONAL IfcStrippedOptional;
DefiningUnit | : | OPTIONAL IfcStrippedOptional;
DefinedUnit | : | OPTIONAL IfcStrippedOptional;
CurveInterpolation | : | OPTIONAL IfcStrippedOptional;

| WHERE

WR21 | : | (NOT(EXISTS(DefiningValues)) AND NOT(EXISTS(DefinedValues))) OR (SIZEOF(DefiningValues) = SIZEOF(DefinedValues));
WR22 | : | NOT(EXISTS(DefiningValues)) OR (SIZEOF(QUERY(temp <* SELF.DefiningValues | TYPEOF(temp) <> TYPEOF(SELF.DefiningValues[1]) )) = 0);
WR23 | : | NOT(EXISTS(DefinedValues)) OR (SIZEOF(QUERY(temp <* SELF.DefinedValues | TYPEOF(temp) <> TYPEOF(SELF.DefinedValues[1]) )) = 0);

END_ENTITY;

Attribute Definitions:

DefiningValues | : | List of defining values, which determine the defined values. This list shall have unique values only. IFC4 CHANGE The attribute has been made optional with upward compatibility for file based exchange.
DefinedValues | : | Defined values which are applicable for the scope as defined by the defining values. IFC4 CHANGE The attribute has been made optional with upward compatibility for file based exchange.
Expression | : | Expression for the derivation of defined values from the defining values, the expression is given for information only, i.e. no automatic processing can be expected from the expression.
DefiningUnit | : | Unit for the defining values, if not given, the default value for the measure type (given by the TYPE of the defining values) is used as defined by the global unit assignment at IfcProject.
DefinedUnit | : | Unit for the defined values, if not given, the default value for the measure type (given by the TYPE of the defined values) is used as defined by the global unit assignment at IfcProject.

Formal Propositions:

WR21 | : | Either both DefiningValues and DefinedValues are not provided, or the number of members in the list of DefiningValues shall be the same as the number of members in the list of DefinedValues.

WR22 : If DefiningValues are provided, then all values within the list of DefiningValues shall have the same measure type.
WR23 : If DefinedValues are provided, then all values within the list of DefinedValues shall have the same measure type.

Inheritance Graph:

ENTITY IfcPropertyTableValue

| ENTITY IfcPropertyAbstraction

| INVERSE

| ENTITY IfcProperty

Name | : | IfcIdentifier;
Description | : | OPTIONAL IfcStrippedOptional;

| INVERSE

PartOfPset | : | SET OF IfcPropertySet FOR HasProperties;

| ENTITY IfcSimpleProperty

| ENTITY IfcPropertyTableValue

DefiningValues | : | OPTIONAL LIST [1:?] OF UNIQUE IfcStrippedOptional;
DefinedValues | : | OPTIONAL LIST [1:?] OF IfcStrippedOptional;
Expression | : | OPTIONAL IfcStrippedOptional;
DefiningUnit | : | OPTIONAL IfcStrippedOptional;
DefinedUnit | : | OPTIONAL IfcStrippedOptional;
CurveInterpolation | : | OPTIONAL IfcStrippedOptional;

END_ENTITY;

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