Примеры использования Functor на Английском языке и их переводы на Русский язык
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It can be seen as a functor in two arguments.
Let c be an object of the category C,and consider the functor Hom-, c.
Not every functor G: C→ D admits a left adjoint.
Flat resolutions can be used to compute the Tor functor.
This functor is left exact, but not necessarily right exact.
Let C be a category, and let F be a contravariant functor from C to the category of sets Set.
The functor FA is exact if and only if A is projective.
In other words, there is a contravariant functor that gives an equivalence between the categories.
This functor takes an object c′ of C and gives back all of the morphisms c′→c.
Here, S{\displaystyle S} has domain 1 and T{\displaystyle T} is an identity functor.
A functor to the comma category selects that particular collection of morphisms.
The fact that there does not exist any faithful functor from hTop to Set was first proven by Peter Freyd.
A functor whose domain is a product category is known as a bifunctor.
The main problem is to prove a signalizer functor theorem for nonsolvable signalizer functors. .
A multifunctor is a generalization of the functor concept to n variables.
In mathematics, specifically in category theory,an F{\displaystyle F}-coalgebra is a structure defined according to a functor F{\displaystyle F.
The divided power functor is used in the construction of co-Schur functors. .
The exponential Z Y{\displaystyle Z^{Y}}is given by a universal morphism from the product functor-× Y{\displaystyle-\times Y} to the object Z{\displaystyle Z.
Every functor F: D→ E induces a functor FC: DC→ EC by composition with F.
One may also start with a contravariant left-exact functor F; the resulting right-derived functors are then also contravariant.
The Hom functor is a natural example; it is contravariant in one argument, covariant in the other.
One also talks about injective objects in categories more general than module categories,for instance in functor categories or in categories of sheaves of OX-modules over some ringed space X.
The direct image functor is the primary operation on sheaves, with the simplest definition.
It takes a presheaf F and produces a new sheaf aF called the sheaving, sheafification orsheaf associated to the presheaf F. The functor a is called the sheaving functor, sheafification functor, or associated sheaf functor. .
Due to this circumstance, a functor with these properties is sometimes called a weak equivalence of categories.
In this way, Spec{\displaystyle\operatorname{Spec}} can be seen as a contravariant functor from the category of commutative rings to the category of topological spaces.
Note that a functor of the form Hom(-, A): Cop→ Set is a presheaf; likewise, Hom(A,-) is a copresheaf.
The Schreier conjecture The Signalizer functor theorem The B conjecture The Schur-Zassenhaus theorem for all groups though this only uses the Feit-Thompson theorem.
This functor makes it possible to think of the objects of the category as sets with additional structure, and of its morphisms as structure-preserving functions.
A strict monoidal functor is a monoidal functor whose coherence maps are identities.