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Mathlib.CategoryTheory.Limits.Preserves.SigmaConst

sigmaConst.obj preserves colimits #

Given an object R in a category C with coproducts of size w, the functor sigmaConst.obj R : Type w ⥤ C which sends a type T to the coproduct of copies of R indexed by T preserves all colimits.

noncomputable def CategoryTheory.Limits.sigmaConstCokernelCofork {C : Type u} [Category.{v, u} C] [HasZeroMorphisms C] (R : C) {α : Type u_1} {β : Type u_2} (f : αβ) [HasCoproduct fun (x : α) => R] [HasCoproduct fun (x : β) => R] [HasCoproduct fun (x : (Set.range f)) => R] :

A colimit cokernel cofork for the map ∐ fun (_ : α) ↦ R ⟶ ∐ fun (_ : β) ↦ R induced by a map f : α → β.

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Instances For
    @[simp]
    theorem CategoryTheory.Limits.sigmaConstCokernelCofork_pt {C : Type u} [Category.{v, u} C] [HasZeroMorphisms C] (R : C) {α : Type u_1} {β : Type u_2} (f : αβ) [HasCoproduct fun (x : α) => R] [HasCoproduct fun (x : β) => R] [HasCoproduct fun (x : (Set.range f)) => R] :
    (sigmaConstCokernelCofork R f).pt = fun (x : (Set.range f)) => R
    theorem CategoryTheory.Limits.ι_sigmaConstCokernelCofork_π {C : Type u} [Category.{v, u} C] [HasZeroMorphisms C] (R : C) {α : Type u_1} {β : Type u_2} (f : αβ) [HasCoproduct fun (x : α) => R] [HasCoproduct fun (x : β) => R] [HasCoproduct fun (x : (Set.range f)) => R] (b : β) (hb : bSet.range f) :
    CategoryStruct.comp (Sigma.ι (fun (x : β) => R) b) (Cofork.π (sigmaConstCokernelCofork R f)) = Sigma.ι (fun (x : (Set.range f)) => R) b, hb
    theorem CategoryTheory.Limits.ι_sigmaConstCokernelCofork_π_assoc {C : Type u} [Category.{v, u} C] [HasZeroMorphisms C] (R : C) {α : Type u_1} {β : Type u_2} (f : αβ) [HasCoproduct fun (x : α) => R] [HasCoproduct fun (x : β) => R] [HasCoproduct fun (x : (Set.range f)) => R] (b : β) (hb : bSet.range f) {Z : C} (h : ( fun (x : (Set.range f)) => R) Z) :
    @[simp]
    theorem CategoryTheory.Limits.ι_sigmaConstCokernelCofork_π_eq_zero {C : Type u} [Category.{v, u} C] [HasZeroMorphisms C] (R : C) {α : Type u_1} {β : Type u_2} (f : αβ) [HasCoproduct fun (x : α) => R] [HasCoproduct fun (x : β) => R] [HasCoproduct fun (x : (Set.range f)) => R] (a : α) :
    CategoryStruct.comp (Sigma.ι (fun (x : β) => R) (f a)) (Cofork.π (sigmaConstCokernelCofork R f)) = 0
    @[simp]
    theorem CategoryTheory.Limits.ι_sigmaConstCokernelCofork_π_eq_zero_assoc {C : Type u} [Category.{v, u} C] [HasZeroMorphisms C] (R : C) {α : Type u_1} {β : Type u_2} (f : αβ) [HasCoproduct fun (x : α) => R] [HasCoproduct fun (x : β) => R] [HasCoproduct fun (x : (Set.range f)) => R] (a : α) {Z : C} (h : ( fun (x : (Set.range f)) => R) Z) :
    noncomputable def CategoryTheory.Limits.isColimitSigmaConstCokernelCofork {C : Type u} [Category.{v, u} C] [HasZeroMorphisms C] (R : C) {α : Type u_1} {β : Type u_2} (f : αβ) [HasCoproduct fun (x : α) => R] [HasCoproduct fun (x : β) => R] [HasCoproduct fun (x : (Set.range f)) => R] :

    The cokernel of the map ∐ fun (_ : α) ↦ R ⟶ ∐ fun (_ : β) ↦ R induced by a map f : α → β identifies to the coproduct of copies of R indexed by the complement of the range of f.

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    Instances For
      instance CategoryTheory.Limits.instHasCokernelMap'Id {C : Type u} [Category.{v, u} C] [HasZeroMorphisms C] (R : C) {α : Type u_1} {β : Type u_2} (f : αβ) [HasCoproduct fun (x : α) => R] [HasCoproduct fun (x : β) => R] [HasCoproduct fun (x : (Set.range f)) => R] :