CanBeDomainUnit
Value type CanBeDomainUnit
definition
CanBeDomainUnit is the group of value types that can be used for a Domain unit.
The applies to sections of many Operators and functions refer to this group, for arguments that need to be a domain unit or a relation towards a domain unit.
value types
The group consists of the value types marked in the Can Be Domain Unit column of the Value type table:
- Uint8, Uint16, Uint32, Uint64: unsigned integers, the most commonly used value types for one-dimensional (table) domains
- Int8, Int16, Int32, Int64: signed integers
- Bool, Uint2, Uint4: sub byte unsigned integers, for domains with a very limited set of elements
- Spoint, Wpoint, Ipoint, Upoint: point value types with integer coordinates, used for two-dimensional (raster) domains
Furthermore the Void value type is in this group; it is used as the (implicit) domain unit of a Parameter, with exactly one element.
why
A domain unit defines the set of entries of its attributes, so its value type must be countable, with a defined range of values that maps one-to-one to the row (or row and column) numbers of the domain.
Units with a Float32, Float64, Fpoint, Dpoint or String value type are not countable and can therefore not be used as domain unit.