functor

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functor

[′fəŋk·tər]
(computer science)
(mathematics)
A function between categories which associates objects with objects and morphisms with morphisms.

functor

In category theory, a functor F is an operator on types. F is also considered to be a polymorphic operator on functions with the type

F : (a -> b) -> (F a -> F b).

Functors are a generalisation of the function "map". The type operator in this case takes a type T and returns type "list of T". The map function takes a function and applies it to each element of a list.
References in periodicals archive ?
G] whose objects are pairs (Q,F : Q [right arrow]* G) consisting of a groupoid and a star injective functor from this groupoid to the group G, and whose morphisms are functors between groupoids which entwine their respective star injective functors to G [51].
With these Hardy inequalities, the Hardy inequalities on rearrangement-invariant Hardy space are established by using the interpolation functor introduced in [15].
A quantum screen network (QS) can be defined as a Functor from the edge screen network ES to the category of Hilbert spaces.
Definition 2 A species (with restrictions) is a contravariant functor P: [set.
But since verbs take nouns as an argument only via functors, the valency is rather more extended.
The functor is a mapping from one category to another, preserving the categorical structure.
What distinguishes the PGI effort from source translators such as swan and mcuda; the ocelot open emulator and PTX translation project; or the ability of the NVIDIA nvcc compiler to generate both x86 and GPU based functors with thrust is:
Among the topics are graded vector spaces, bilax monoidal functors in homological algebra, higher monoidal categories, universal constructions of Hopf monoids, Hopf monoids in colored species, deformations of Fock functors, and decorated Fock functors and creation-annihilation.
The narrative function is losing its functors, its great hero, its great dangers, its great voyages, its great goal.
Mazzola and Andreatta insist that music and mathematics involve common structures that can be related by the notion of adjoint functors.
Thus a hierarchial evolutive system is then an evolutive system in which the state category at each value t is hierarchial and the transition functors preserve the levels.
These functors are very useful in modern algebraic geometry, e.