Population

Purpose

To store data in a database corresponds to populating the relations in a context. Atoms are the data and pairs of atoms are inserted and deleted during the lifetime of a relation.

Description

All pairs in a relation are called the population of that relation. All atoms in a concept constitute the population of that concept. The population of all relations and concepts in a context make the population of that context.

There are two ways to populate a concept with atoms:

• A POPULATION statement defines the initial population of a concept or a relation.

• An INCLUDE statement defines the initial population from an xlsx-file (i.e. an Excel speadsheet)

Using spreadsheets to define an initial population allows you to work with larger populations. Often you can use an existing spreadsheet and adapt it to become acceptable as Ampersand input.

Syntax

You can define atoms separately and you can define the pairs in a relation. Both methods result in added population for each concept.

POPULATION Tree CONTAINS
    [ "Oak"
    , "Birch"
    , "Willow"
    ]

POPULATION personBank[Person*Bank] CONTAINS
    [ ("John", "ING")
    , ("Jane", "TRIODOS")
    ]

The list of pairs is a comma-separated list between square brackets. Pairs are comma-separated pairs between round brackets. Each atom is enclosed in double quotes.