Category Of Relations
In mathematics, the category Rel has the class of sets as objects and binary relations as morphisms.
A morphism (or arrow) R : A → B in this category is a relation between the sets A and B, so R ⊆ A × B.
The composition of two relations R: A → B and S: B → C is given by:
- (a, c) ∈ S R if (and only if) for some b ∈ B, (a, b) ∈ R and (b, c) ∈ S.
Read more about Category Of Relations: Properties
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