Search results
Results from the WOW.Com Content Network
Two disjoint sets. In set theory in mathematics and formal logic, two sets are said to be disjoint sets if they have no element in common. Equivalently, two disjoint sets are sets whose intersection is the empty set. [1] For example, {1, 2, 3} and {4, 5, 6} are disjoint sets, while {1, 2, 3} and {3, 4, 5} are not disjoint. A collection of two ...
In mathematics, the disjoint union (or discriminated union) of the sets A and B is the set formed from the elements of A and B labelled (indexed) with the name of the set from which they come. So, an element belonging to both A and B appears twice in the disjoint union, with two different labels.
The set of those translates partitions the circle into a countable collection of pairwise disjoint sets, which are all pairwise congruent. Since X is not measurable for any rotation-invariant countably additive finite measure on S , finding an algorithm to form a set from selecting a point in each orbit requires that one add the axiom of choice ...
Pairwise generally means "occurring in pairs" or "two at a time." Pairwise may also refer to: Pairwise disjoint; Pairwise independence of random variables; Pairwise comparison, the process of comparing two entities to determine which is preferred; All-pairs testing, also known as pairwise testing, a software testing method.
A partition of a set S is a set of non-empty, pairwise disjoint subsets of S, called "parts" or "blocks", whose union is all of S.Consider a finite set that is linearly ordered, or (equivalently, for purposes of this definition) arranged in a cyclic order like the vertices of a regular n-gon.
To define the join, form a relation on the blocks A of α and the blocks B of ρ by A ~ B if A and B are not disjoint. Then α ∨ ρ {\displaystyle \alpha \vee \rho } is the partition in which each block C is the union of a family of blocks connected by this relation.
Then consider ,, …, to be a maximal collection of pairwise disjoint sets (that is, is the empty set unless =, and every set in intersects with some ). Because we assumed that W {\displaystyle W} had no sunflower of size r {\displaystyle r} , and a collection of pairwise disjoint sets is a sunflower, t < r {\displaystyle t<r} .
This definition extends to any collection of sets. A collection of sets is pairwise almost disjoint or mutually almost disjoint if any two distinct sets in the collection are almost disjoint. Often the prefix 'pairwise' is dropped, and a pairwise almost disjoint collection is simply called "almost disjoint". Formally, let I be an index set, and ...