Numbering scheme

There are many different numbering schemes for assigning nominal numbers to entities. These generally require an agreed set of rules, or a central coordinator. The schemes can be considered to be examples of a primary key of a database management system table, whose table definitions require a database design.

In computability theory, the simplest numbering scheme is the assignment of natural numbers to a set of objects such as functions, rational numbers, graphs, or words in some language. A numbering can be used to transfer the idea of computability and related concepts, which are originally defined on the natural numbers using computable functions, to these different types of objects.

A simple extension is to assign cardinal numbers to physical objects according to the choice of some base of reference and of measurement units for counting or measuring these objects within a given precision. In such case, numbering is a kind of classification, i.e. assigning a numeric property to each object of the set to subdivide this set into related subsets forming a partition of the initial set, possibly infinite and not enumeratable using a single natural number for each class of the partition.

In some cases (such as computing, time-telling, and in some countries the numbering of floors in buildings) zero-based numbering is used, where the first entity is assigned "zero" instead of "one".

Other numbering schemes are listed by field below.

Chemistry

Communications

Products

People

Identification numbers

Ordinals for names

Topics

Geography and transport

See also: Country code; Address (geography).

Vehicles

Roads

Road numbering schemes

Others/general
gollark: Mrmola's goals are beyond the understanding of us mortal beings/
gollark: What does mola have that data for?
gollark: OH NO IT STARTED AGAIN ÅAAAAA
gollark: > Someone in charge of the Discord bots here should write or extend a bot to replace a regex match to replace 0/0 or x/0 by UNDEFINED automatically. Something like re.replace([0-9]*/ 0, UNDEFINED , string) (simplified because I am lazy) , so MrMola can no longer type 0 / 0 and it's automatically shown as UNDEFINED :- )<@520480232738652161> Bots and moderators cannot, for extremely obvious reasons, edit other people's messages.
gollark: As opposed to partial ordering, where some pairs of elements can't be ordered.

See also

References
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