DISJOINT UNION

Domain	Definition
Computing	Disjoint union In domain theory, a union (or sum) which results in a domain without a least element. Source: The Free On-line Dictionary of Computing.
Source: compiled by the editor from various references; see credits.

Specialty Definition: Disjoint union

In set theory, a disjoint union is a type of union (Set theoretic union), in which each element of the union is disjoint from the others: intersection with every other element of the union is the empty set.

i.e. Suppose C is a collection of sets, then:

is a disjoint union if and only if

To take the disjoint union of sets that are not in fact disjoint, one can use an indexing device. For example given A₁ and A₂, which may have common elements, with union B, the disjoint union as a subset of B x {1,2} is the union of A₁ x {1} and A₂x{2}.

See also: Basic Set Theory

Anagrams: DISJOINT UNION

Scrabble® Enable2K-Verified Anagrams
	Words within the letters "d-i-i-i-j-n-n-n-o-o-s-t-u"
	-5 letters: disjoint, disunion, unionist, unjoints.
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