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Structures · Category theory

CategoryTheory.Functor.EssSurj

A functor F : C ⥤ D is essentially surjective if every object of D is in the essential image of F. In other words, for every Y : D, there is some X : C with F.obj X ≅ Y.

Defined in
Mathlib.CategoryTheory.EssentialImage
Shape
One type argument · adds mem_essImage

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Concrete types that are instances26

  • CategoryTheory.Over
  • ModuleCat
  • HomologicalComplex
  • CategoryTheory.Quotient
  • CategoryTheory.Skeleton
  • CategoryTheory.Comma
  • HomotopyCategory
  • CategoryTheory.Under
  • CategoryTheory.InducedCategory
  • CategoryTheory.CostructuredArrow
  • CategoryTheory.StructuredArrow
  • CategoryTheory.Arrow
  • CategoryTheory.Bundled.α
  • CategoryTheory.Comonad.Coalgebra
  • CategoryTheory.Monad.Algebra
  • CategoryTheory.Mat_
  • Compactum
  • LightDiagram'
  • CochainComplex
  • CochainComplex.Plus
  • SimplexCategory
  • HomotopyCategory.Plus
  • FintypeCat.Skeleton
  • CategoryTheory.Decomposed
  • Opposite
  • Sum

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