Mapping

Relational functions mapping

syntax

• mapping(SrcUnit, DstUnit)

definition

mapping(SrcUnit, DstUnit) results in a relation with the Index numbers of the Domain unit DstUnit. The resulting Attribute has as Values unit DstUnit and as domain unit SrcUnit.

description

mapping(SrcUnit, DstUnit) is equivalent with Convert(Id (SrcUnit), DstUnit), but requires less memory.

applies to

• SrcUnit, DstUnit units with value types of the group CanBeDomainUnit

since version

7.119

example

unit<uint32> RegionSrc: nrofrows = 5;
unit<uint32> RegionDst: nrofrows = 5;
attribute<RegionDst> RegionDst_rel (RegionSrc) := mapping(RegionSrc, RegionDst);

RegionDst_rel
0
1
2
3
4

domain RegionSrc, nr of rows = 5

see also

• Mapping_count