mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.AlgebraicTopology.SimplicialSet.StdSimplex

Goal state before:
pp: n : ℕ
x : Δ[n] _⦋0⦌
⊢ (fun i ↦ const n i (op ⦋0⦌)) ((fun x ↦ x 0) x) = x

Tactic:
ext i : 1

Goal state after:
n : ℕ
x : Δ[n] _⦋0⦌
i : Fin (0 + 1)
⊢ ((fun i ↦ const n i (op ⦋0⦌)) ((fun x ↦ x 0) x)) i = x i
Module: Mathlib.AlgebraicTopology.SimplicialSet.StdSimplex

Goal state before:
pp: n : ℕ
x✝¹ : SimplexCategoryᵒᵖ
x✝ : Δ[n].obj x✝¹
⊢ x✝ ∈ (face univ).obj x✝¹

Tactic:
apply Finset.subset_univ

Goal state after:
Module: Mathlib.Algebra.Homology.ComplexShapeSigns

Goal state before:
pp: I₁ : Type u_1
I₂ : Type u_2
I₁₂ : Type u_4
c₁ : ComplexShape I₁
c₂ : ComplexShape I₂
c₁₂ : ComplexShape I₁₂
inst✝ : TotalComplexShape c₁ c₂ c₁₂
i₁ i₁' : I₁
i₂ i₂' : I₂
h₁ : c₁.Rel i₁ i₁'
h₂ : c₂.Rel i₂ i₂'
⊢ c₁.ε₁ c₂ c₁₂ (i₁, i₂) * (c₁.ε₂ c₂ c₁₂ (i₁, i₂) * (c₁.ε₁ c₂ c₁₂ (i₁, i₂') * c₁.ε₁ c₂ c₁₂ (i₁, i₂'))) =
    -c₁.ε₂ c₂ c₁₂ (i₁', i₂) * c₁.ε₁ c₂ c₁₂ (i₁, i₂')

Tactic:
conv_lhs =>
      arg 2
      rw [← mul_assoc, ε₂_ε₁ c₁₂ h₁ h₂]

Goal state after:
I₁ : Type u_1
I₂ : Type u_2
I₁₂ : Type u_4
c₁ : ComplexShape I₁
c₂ : ComplexShape I₂
c₁₂ : ComplexShape I₁₂
inst✝ : TotalComplexShape c₁ c₂ c₁₂
i₁ i₁' : I₁
i₂ i₂' : I₂
h₁ : c₁.Rel i₁ i₁'
h₂ : c₂.Rel i₂ i₂'
⊢ c₁.ε₁ c₂ c₁₂ (i₁, i₂) * (-c₁.ε₁ c₂ c₁₂ (i₁, i₂) * c₁.ε₂ c₂ c₁₂ (i₁', i₂) * c₁.ε₁ c₂ c₁₂ (i₁, i₂')) =
    -c₁.ε₂ c₂ c₁₂ (i₁', i₂) * c₁.ε₁ c₂ c₁₂ (i₁, i₂')
Module: Mathlib.Algebra.Homology.TotalComplex

Goal state before:
pp: case pos
C : Type u_1
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : Preadditive C
I₁ : Type u_2
I₂ : Type u_3
I₁₂ : Type u_4
c₁ : ComplexShape I₁
c₂ : ComplexShape I₂
K : HomologicalComplex₂ C c₁ c₂
c₁₂ : ComplexShape I₁₂
inst✝² : TotalComplexShape c₁ c₂ c₁₂
inst✝¹ : DecidableEq I₁₂
inst✝ : K.HasTotal c₁₂
i₁₂ i₁₂' : I₁₂
h₁₂ : ¬c₁₂.Rel i₁₂ i₁₂'
i₁ : I₁
i₂ : I₂
h : c₁.π c₂ c₁₂ (i₁, i₂) = i₁₂
h₁ : c₁.Rel i₁ (c₁.next i₁)
h₂ : c₁.π c₂ c₁₂ (c₁.next i₁, i₂) = i₁₂'
⊢ False

Tactic:
exact h₁₂ (by simpa only [← h, ← h₂] using ComplexShape.rel_π₁ c₂ c₁₂ h₁ i₂)

Goal state after:
Module: Mathlib.Algebra.Homology.CochainComplexOpposite

Goal state before:
pp: C : Type u_1
inst✝¹ : Category.{v_1, u_1} C
inst✝ : Preadditive C
K L : CochainComplex C ℤ
f g : K ⟶ L
h : Homotopy f g
p q : ℤ
hpq : ¬(ComplexShape.up ℤ).Rel q p
⊢ (h.hom (-q) (-p)).op = 0

Tactic:
rw [h.zero, op_zero]
    dsimp at hpq ⊢
    lia

Goal state after:
Module: Mathlib.Algebra.Homology.HomotopyCategory.HomComplexInduction

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
K L : CochainComplex C ℤ
d : ℤ
X : ℕ → Set (Cochain K L d)
φ : (n : ℕ) → ↑(X n) → ↑(X (n + 1))
p₀ : ℤ
hφ : ∀ (n : ℕ) (x : ↑(X n)), (↑(φ n x)).EqUpTo (↑x) (p₀ + ↑n)
x₀ : ↑(X 0)
n : ℕ
⊢ (limitSequence φ hφ x₀).EqUpTo (↑(sequence φ x₀ n)) (p₀ + ↑n)

Tactic:
intro p q hpq hp
  exact sequence_eqUpTo φ hφ _ _ _ (by lia) _ _ _ (by lia)

Goal state after:
Module: Mathlib.CategoryTheory.Triangulated.TStructure.Basic

Goal state before:
pp: C : Type u_1
inst✝⁶ : Category.{v_1, u_1} C
inst✝⁵ : Preadditive C
inst✝⁴ : HasZeroObject C
inst✝³ : HasShift C ℤ
inst✝² : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝¹ : Pretriangulated C
t : TStructure C
X : C
n a n' : ℤ
hn' : a + n' = n
inst✝ : t.IsLE ((shiftFunctor C a).obj X) n'
⊢ t.IsLE X n

Tactic:
have h := t.isLE_shift (X⟦a⟧) n' (-a) n
  exact t.isLE_of_iso (show X⟦a⟧⟦-a⟧ ≅ X from (shiftEquiv C a).unitIso.symm.app X) n

Goal state after:
Module: Mathlib.AlgebraicTopology.ModelCategory.IsCofibrant

Goal state before:
pp: C : Type u_1
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : CategoryWithFibrations C
inst✝² : HasTerminal C
X Y : C
inst✝¹ : (fibrations C).IsStableUnderBaseChange
inst✝ : HasBinaryProduct X Y
hY : Fibration (terminal.from Y)
⊢ Fibration prod.fst

Tactic:
fibration_iff

Goal state after:
C : Type u_1
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : CategoryWithFibrations C
inst✝² : HasTerminal C
X Y : C
inst✝¹ : (fibrations C).IsStableUnderBaseChange
inst✝ : HasBinaryProduct X Y
hY : fibrations C (terminal.from Y)
⊢ fibrations C prod.fst
Module: Mathlib.AlgebraicTopology.ModelCategory.IsCofibrant

Goal state before:
pp: C : Type u_1
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : CategoryWithFibrations C
inst✝² : HasTerminal C
X Y : C
inst✝¹ : (fibrations C).IsStableUnderBaseChange
inst✝ : HasBinaryProduct X Y
hX : Fibration (terminal.from X)
⊢ Fibration prod.snd

Tactic:
fibration_iff

Goal state after:
C : Type u_1
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : CategoryWithFibrations C
inst✝² : HasTerminal C
X Y : C
inst✝¹ : (fibrations C).IsStableUnderBaseChange
inst✝ : HasBinaryProduct X Y
hX : fibrations C (terminal.from X)
⊢ fibrations C prod.snd
Module: Mathlib.AlgebraicTopology.ModelCategory.Instances

Goal state before:
pp: C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : CategoryWithWeakEquivalences C
inst✝³ : CategoryWithCofibrations C
inst✝² : CategoryWithFibrations C
X Y Z : C
f : X ⟶ Z
g : Y ⟶ Z
inst✝¹ : HasPullback f g
inst✝ : (fibrations C).IsStableUnderBaseChange
hf : Fibration f
⊢ Fibration (pullback.snd f g)

Tactic:
fibration_iff

Goal state after:
C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : CategoryWithWeakEquivalences C
inst✝³ : CategoryWithCofibrations C
inst✝² : CategoryWithFibrations C
X Y Z : C
f : X ⟶ Z
g : Y ⟶ Z
inst✝¹ : HasPullback f g
inst✝ : (fibrations C).IsStableUnderBaseChange
hf : fibrations C f
⊢ fibrations C (pullback.snd f g)
Module: Mathlib.AlgebraicTopology.ModelCategory.Instances

Goal state before:
pp: C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : CategoryWithWeakEquivalences C
inst✝³ : CategoryWithCofibrations C
inst✝² : CategoryWithFibrations C
X Y Z : C
f : X ⟶ Z
g : Y ⟶ Z
inst✝¹ : HasPullback f g
inst✝ : (fibrations C).IsStableUnderBaseChange
hg : Fibration g
⊢ Fibration (pullback.fst f g)

Tactic:
fibration_iff

Goal state after:
C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : CategoryWithWeakEquivalences C
inst✝³ : CategoryWithCofibrations C
inst✝² : CategoryWithFibrations C
X Y Z : C
f : X ⟶ Z
g : Y ⟶ Z
inst✝¹ : HasPullback f g
inst✝ : (fibrations C).IsStableUnderBaseChange
hg : fibrations C g
⊢ fibrations C (pullback.fst f g)
Module: Mathlib.AlgebraicTopology.ModelCategory.Instances

Goal state before:
pp: C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : CategoryWithWeakEquivalences C
inst✝³ : CategoryWithCofibrations C
inst✝² : CategoryWithFibrations C
X Y Z : C
f : X ⟶ Z
g : Y ⟶ Z
inst✝¹ : HasPullback f g
inst✝ : (fibrations C).IsStableUnderBaseChange
hg : Fibration g
⊢ Fibration (pullback.fst f g)

Tactic:
rw [fibration_iff] at hg ⊢
  exact MorphismProperty.of_isPullback (IsPullback.of_hasPullback f g).flip hg

Goal state after:
Module: Mathlib.AlgebraicTopology.ModelCategory.Instances

Goal state before:
pp: C : Type u
inst✝⁷ : Category.{v, u} C
inst✝⁶ : CategoryWithWeakEquivalences C
inst✝⁵ : CategoryWithCofibrations C
inst✝⁴ : CategoryWithFibrations C
X Y Z : C
f : X ⟶ Z
g : Y ⟶ Z
inst✝³ : HasPullback f g
inst✝² : (trivialFibrations C).IsStableUnderBaseChange
inst✝¹ : Fibration f
inst✝ : WeakEquivalence f
⊢ weakEquivalences C (pullback.snd f g)

Tactic:
exact (MorphismProperty.of_isPullback (IsPullback.of_hasPullback f g)
    (mem_trivialFibrations f)).2

Goal state after:
Module: Mathlib.AlgebraicTopology.ModelCategory.Instances

Goal state before:
pp: C : Type u
inst✝⁶ : Category.{v, u} C
inst✝⁵ : CategoryWithWeakEquivalences C
inst✝⁴ : CategoryWithCofibrations C
inst✝³ : CategoryWithFibrations C
X₁ X₂ Y₁ Y₂ : C
f₁ : X₁ ⟶ Y₁
f₂ : X₂ ⟶ Y₂
inst✝² : (trivialCofibrations C).IsWeakFactorizationSystem (fibrations C)
h₁ : Fibration f₁
h₂ : Fibration f₂
inst✝¹ : HasBinaryProduct X₁ X₂
inst✝ : HasBinaryProduct Y₁ Y₂
⊢ Fibration (prod.map f₁ f₂)

Tactic:
fibration_iff

Goal state after:
C : Type u
inst✝⁶ : Category.{v, u} C
inst✝⁵ : CategoryWithWeakEquivalences C
inst✝⁴ : CategoryWithCofibrations C
inst✝³ : CategoryWithFibrations C
X₁ X₂ Y₁ Y₂ : C
f₁ : X₁ ⟶ Y₁
f₂ : X₂ ⟶ Y₂
inst✝² : (trivialCofibrations C).IsWeakFactorizationSystem (fibrations C)
h₁ : fibrations C f₁
h₂ : fibrations C f₂
inst✝¹ : HasBinaryProduct X₁ X₂
inst✝ : HasBinaryProduct Y₁ Y₂
⊢ fibrations C (prod.map f₁ f₂)
Module: Mathlib.AlgebraicTopology.ModelCategory.PathObject

Goal state before:
pp: C : Type u
inst✝⁵ : Category.{v, u} C
A : C
inst✝⁴ : CategoryWithWeakEquivalences C
P : PathObject A
inst✝³ : HasBinaryProducts C
inst✝² : CategoryWithFibrations C
inst✝¹ : P.IsGood
inst✝ : (fibrations C).RespectsIso
hp : fibrations C P.p
⊢ Fibration (P.p ≫ (prod.braiding A A).hom)

Tactic:
fibration_iff

Goal state after:
C : Type u
inst✝⁵ : Category.{v, u} C
A : C
inst✝⁴ : CategoryWithWeakEquivalences C
P : PathObject A
inst✝³ : HasBinaryProducts C
inst✝² : CategoryWithFibrations C
inst✝¹ : P.IsGood
inst✝ : (fibrations C).RespectsIso
hp : fibrations C P.p
⊢ fibrations C (P.p ≫ (prod.braiding A A).hom)
Module: Mathlib.AlgebraicTopology.ModelCategory.PathObject

Goal state before:
pp: C : Type u
inst✝⁴ : Category.{v, u} C
inst✝³ : ModelCategory C
A : C
P✝ : PathObject A
inst✝² : IsFibrant A
P P' : PathObject A
inst✝¹ : P.IsGood
inst✝ : P'.IsGood
ψ : (P.trans P').P ⟶ P.P ⨯ A := prod.lift (pullback.fst P.p₁ P'.p₀) (pullback.snd P.p₁ P'.p₀ ≫ P'.p₁)
fac : ψ ≫ prod.map P.p₁ (𝟙 A) = pullback.snd P.p₁ P'.p₀ ≫ P'.p
sq : IsPullback (ψ ≫ prod.fst) (pullback.snd P.p₁ P'.p₀) P.p₁ (P'.p ≫ prod.fst)
⊢ Fibration ψ

Tactic:
fibration_iff

Goal state after:
C : Type u
inst✝⁴ : Category.{v, u} C
inst✝³ : ModelCategory C
A : C
P✝ : PathObject A
inst✝² : IsFibrant A
P P' : PathObject A
inst✝¹ : P.IsGood
inst✝ : P'.IsGood
ψ : (P.trans P').P ⟶ P.P ⨯ A := prod.lift (pullback.fst P.p₁ P'.p₀) (pullback.snd P.p₁ P'.p₀ ≫ P'.p₁)
fac : ψ ≫ prod.map P.p₁ (𝟙 A) = pullback.snd P.p₁ P'.p₀ ≫ P'.p
sq : IsPullback (ψ ≫ prod.fst) (pullback.snd P.p₁ P'.p₀) P.p₁ (P'.p ≫ prod.fst)
⊢ fibrations C ψ
Module: Mathlib.AlgebraicTopology.ModelCategory.LeftHomotopy

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
X Y : C
inst✝ : ModelCategory C
P : Cylinder X
f g : X ⟶ Y
h : P.LeftHomotopy f g
⊢ ∃ P', P'.IsGood ∧ Nonempty (P'.LeftHomotopy f g)

Tactic:
let d := MorphismProperty.factorizationData (cofibrations C) (trivialFibrations C) P.i
  exact
   ⟨{ I := d.Z
      i₀ := coprod.inl ≫ d.i
      i₁ := coprod.inr ≫ d.i
      π := d.p ≫ P.π }, ⟨by
        rw [cofibration_iff]
        convert! d.hi
        aesop⟩, ⟨{ h := d.p ≫ h.h }⟩⟩

Goal state after:
Module: Mathlib.AlgebraicTopology.ModelCategory.RightHomotopy

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
X Y : C
inst✝ : ModelCategory C
P : PathObject Y
f g : X ⟶ Y
h : P.RightHomotopy f g
d : (trivialCofibrations C).MapFactorizationData (fibrations C) P.p :=
  (trivialCofibrations C).factorizationData (fibrations C) P.p
⊢ Fibration
    { P := d.Z, p₀ := d.p ≫ prod.fst, p₁ := d.p ≫ prod.snd, ι := P.ι ≫ d.i, ι_p₀ := ⋯, ι_p₁ := ⋯,
        weakEquivalence_ι := ⋯ }.p

Tactic:
fibration_iff

Goal state after:
C : Type u
inst✝¹ : Category.{v, u} C
X Y : C
inst✝ : ModelCategory C
P : PathObject Y
f g : X ⟶ Y
h : P.RightHomotopy f g
d : (trivialCofibrations C).MapFactorizationData (fibrations C) P.p :=
  (trivialCofibrations C).factorizationData (fibrations C) P.p
⊢ fibrations C
    { P := d.Z, p₀ := d.p ≫ prod.fst, p₁ := d.p ≫ prod.snd, ι := P.ι ≫ d.i, ι_p₀ := ⋯, ι_p₁ := ⋯,
        weakEquivalence_ι := ⋯ }.p
Module: Mathlib.CategoryTheory.Localization.OfQuotient

Goal state before:
pp: C : Type u_1
inst✝¹ : Category.{v_1, u_1} C
r : HomRel C
inst✝ : Congruence r
W : MorphismProperty C
hW : W.IsInvertedBy (functor r)
hr : ∀ ⦃X Y : C⦄ (f₀ f₁ : X ⟶ Y), r f₀ f₁ → ∃ P x, W P.ι
X Y : C
f₀ f₁ : X ⟶ Y
hf : (functor r).map f₀ = (functor r).map f₁
⊢ ∃ P x, W P.ι

Tactic:
rw [functor_map_eq_iff] at hf
      exact hr _ _ hf

Goal state after:
Module: Mathlib.Algebra.Homology.HomotopyCategory.Plus

Goal state before:
pp: C : Type u_1
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : Preadditive C
inst✝² : HasBinaryBiproducts C
K L : CochainComplex C ℤ
f : K ⟶ L
n₁ n₂ n : ℤ
inst✝¹ : K.IsStrictlyGE n₁
inst✝ : L.IsStrictlyGE n₂
hn₁ : n < n₁
hn₂ : n ≤ n₂
i : ℤ
hi : i < n
⊢ IsZero ((mappingCone f).X i)

Tactic:
simp only [mappingCone.isZero_X_iff]

Goal state after:
C : Type u_1
inst✝⁴ : Category.{v_1, u_1} C
inst✝³ : Preadditive C
inst✝² : HasBinaryBiproducts C
K L : CochainComplex C ℤ
f : K ⟶ L
n₁ n₂ n : ℤ
inst✝¹ : K.IsStrictlyGE n₁
inst✝ : L.IsStrictlyGE n₂
hn₁ : n < n₁
hn₂ : n ≤ n₂
i : ℤ
hi : i < n
⊢ IsZero (K.X (i + 1)) ∧ IsZero (L.X i)
Module: Mathlib.Algebra.Homology.HomotopyCategory.Plus

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝⁶ : Category.{v_1, u_1} C
inst✝⁵ : Category.{v_2, u_2} D
inst✝⁴ : Preadditive C
inst✝³ : Preadditive D
A : Type u_3
inst✝² : Category.{v_3, u_3} A
inst✝¹ : Abelian A
inst✝ : HasZeroObject C
⊢ plus C ((quotient C (ComplexShape.up ℤ)).obj 0)

Tactic:
simp only [plus_quotient_obj_iff]
      exact ⟨0, inferInstance⟩

Goal state after:
Module: Mathlib.Algebra.Homology.HomotopyCategory.Plus

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝⁵ : Category.{v_1, u_1} C
inst✝⁴ : Category.{v_2, u_2} D
inst✝³ : Preadditive C
inst✝² : Preadditive D
A : Type u_3
inst✝¹ : Category.{v_3, u_3} A
inst✝ : Abelian A
n : ℤ
K : CochainComplex C ℤ
hK : plus C ((quotient C (ComplexShape.up ℤ)).obj K)
⊢ (plus C).shift n ((quotient C (ComplexShape.up ℤ)).obj K)

Tactic:
simp only [plus_quotient_obj_iff] at hK

Goal state after:
C : Type u_1
D : Type u_2
inst✝⁵ : Category.{v_1, u_1} C
inst✝⁴ : Category.{v_2, u_2} D
inst✝³ : Preadditive C
inst✝² : Preadditive D
A : Type u_3
inst✝¹ : Category.{v_3, u_3} A
inst✝ : Abelian A
n : ℤ
K : CochainComplex C ℤ
hK : CochainComplex.plus C K
⊢ (plus C).shift n ((quotient C (ComplexShape.up ℤ)).obj K)
Module: Mathlib.Algebra.Homology.HomotopyCategory.Plus

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝⁵ : Category.{v_1, u_1} C
inst✝⁴ : Category.{v_2, u_2} D
inst✝³ : Preadditive C
inst✝² : Preadditive D
A : Type u_3
inst✝¹ : Category.{v_3, u_3} A
inst✝ : Abelian A
⊢ ∀ (X : CochainComplex.Plus C),
    plus C ((CochainComplex.Plus.ι C ⋙ HomotopyCategory.quotient C (ComplexShape.up ℤ)).obj X)

Tactic:
by
      rintro ⟨K, h⟩
      simpa [plus_quotient_obj_iff]

Goal state after:
Module: Mathlib.CategoryTheory.Triangulated.TStructure.Induced

Goal state before:
pp: C : Type u_1
inst✝⁸ : Category.{v_1, u_1} C
inst✝⁷ : Preadditive C
inst✝⁶ : HasZeroObject C
inst✝⁵ : HasShift C ℤ
inst✝⁴ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝³ : Pretriangulated C
P : ObjectProperty C
inst✝² : P.IsTriangulated
t : TStructure C
inst✝¹ : P.IsClosedUnderIsomorphisms
inst✝ : P.HasInducedTStructure t
T : Triangle C
hT : T ∈ distinguishedTriangles
n₀ n₁ : ℤ
h : n₀ + 1 = n₁
h₁ : t.IsLE T.obj₁ n₀
h₂ : P T.obj₂
h₃ : t.IsGE T.obj₃ n₁
⊢ t.IsLE (P.ι.mapTriangle.obj (((P.tStructure t).triangleLEGE n₀ n₁ h).obj { obj := T.obj₂, property := h₂ })).obj₁ n₀

Tactic:
dsimp; rw [← P.tStructure_isLE_iff]; infer_instance

Goal state after:
Module: Mathlib.CategoryTheory.Triangulated.LocalizingSubcategory

Goal state before:
pp: C : Type u_1
D : Type u_2
D₁ : Type u_3
D₂ : Type u_4
inst✝¹⁵ : Category.{v_1, u_1} C
inst✝¹⁴ : Category.{v_2, u_2} D
inst✝¹³ : Category.{v_3, u_3} D₁
inst✝¹² : Category.{v_4, u_4} D₂
A B : ObjectProperty C
inst✝¹¹ : HasZeroObject C
inst✝¹⁰ : HasShift C ℤ
inst✝⁹ : Preadditive C
inst✝⁸ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁷ : Pretriangulated C
inst✝⁶ : IsTriangulated C
inst✝⁵ : A.IsTriangulated
inst✝⁴ : B.IsTriangulated
inst✝³ : B.IsClosedUnderIsomorphisms
inst✝² : A.IsVerdierRightLocalizing B
L₁ : A.FullSubcategory ⥤ D₁
L₂ : C ⥤ D₂
inst✝¹ : L₁.IsLocalization (B.inverseImage A.ι).trW
inst✝ : L₂.IsLocalization B.trW
F : D₁ ⥤ D₂ := (A.triangulatedLocalizerMorphism B).localizedFunctor L₁ L₂
this✝ : L₁.EssSurj
e : A.ι ⋙ L₂ ≅ L₁ ⋙ F := CatCommSq.iso (A.triangulatedLocalizerMorphism B).functor L₁ L₂ F
X₁ X₂ : A.FullSubcategory
φ : F.obj (L₁.obj X₁) ⟶ F.obj (L₁.obj X₂)
φ' : (A.ι ⋙ L₂).obj X₁ ⟶ (A.ι ⋙ L₂).obj X₂
hφ' : φ = e.inv.app X₁ ≫ φ' ≫ e.hom.app X₂
f : B.trW.LeftFraction (A.ι.obj X₁) (A.ι.obj X₂)
hf : φ' = f.map L₂ ⋯
X₃ : C
s' : A.ι.obj X₂ ⟶ X₃
a : f.Y' ⟶ X₃
hX₃ : A X₃
hs' : (A ⊓ B).trW s'
fac : f.s ≫ a = s'
g : (B.inverseImage A.ι).trW.LeftFraction X₁ X₂ :=
  { Y' := { obj := X₃, property := hX₃ }, f := homMk (f.f ≫ a), s := homMk s', hs := ⋯ }
this : IsIso (L₁.map g.s)
⊢ F.map (g.map L₁ ⋯) = φ

Tactic:
rw [← cancel_mono (F.map (L₁.map g.s)), ← Functor.map_comp,
    MorphismProperty.LeftFraction.map_comp_map_s]

Goal state after:
C : Type u_1
D : Type u_2
D₁ : Type u_3
D₂ : Type u_4
inst✝¹⁵ : Category.{v_1, u_1} C
inst✝¹⁴ : Category.{v_2, u_2} D
inst✝¹³ : Category.{v_3, u_3} D₁
inst✝¹² : Category.{v_4, u_4} D₂
A B : ObjectProperty C
inst✝¹¹ : HasZeroObject C
inst✝¹⁰ : HasShift C ℤ
inst✝⁹ : Preadditive C
inst✝⁸ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁷ : Pretriangulated C
inst✝⁶ : IsTriangulated C
inst✝⁵ : A.IsTriangulated
inst✝⁴ : B.IsTriangulated
inst✝³ : B.IsClosedUnderIsomorphisms
inst✝² : A.IsVerdierRightLocalizing B
L₁ : A.FullSubcategory ⥤ D₁
L₂ : C ⥤ D₂
inst✝¹ : L₁.IsLocalization (B.inverseImage A.ι).trW
inst✝ : L₂.IsLocalization B.trW
F : D₁ ⥤ D₂ := (A.triangulatedLocalizerMorphism B).localizedFunctor L₁ L₂
this✝ : L₁.EssSurj
e : A.ι ⋙ L₂ ≅ L₁ ⋙ F := CatCommSq.iso (A.triangulatedLocalizerMorphism B).functor L₁ L₂ F
X₁ X₂ : A.FullSubcategory
φ : F.obj (L₁.obj X₁) ⟶ F.obj (L₁.obj X₂)
φ' : (A.ι ⋙ L₂).obj X₁ ⟶ (A.ι ⋙ L₂).obj X₂
hφ' : φ = e.inv.app X₁ ≫ φ' ≫ e.hom.app X₂
f : B.trW.LeftFraction (A.ι.obj X₁) (A.ι.obj X₂)
hf : φ' = f.map L₂ ⋯
X₃ : C
s' : A.ι.obj X₂ ⟶ X₃
a : f.Y' ⟶ X₃
hX₃ : A X₃
hs' : (A ⊓ B).trW s'
fac : f.s ≫ a = s'
g : (B.inverseImage A.ι).trW.LeftFraction X₁ X₂ :=
  { Y' := { obj := X₃, property := hX₃ }, f := homMk (f.f ≫ a), s := homMk s', hs := ⋯ }
this : IsIso (L₁.map g.s)
⊢ F.map (L₁.map g.f) = φ ≫ F.map (L₁.map g.s)
Module: Mathlib.CategoryTheory.Triangulated.TStructure.TruncLTGE

Goal state before:
pp: C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : Preadditive C
inst✝³ : HasZeroObject C
inst✝² : HasShift C ℤ
inst✝¹ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝ : Pretriangulated C
t : TStructure C
n₀ n₁ : ℤ
h : n₀ + 1 = n₁
X : C
⊢ t.IsLE X n₀ ↔ IsZero ((t.truncGE n₁).obj X)

Tactic:
by
  rw [t.isLE_iff_isIso_truncLTι_app n₀ n₁ h X]
  exact (Triangle.isZero₃_iff_isIso₁ _ (t.triangleLTGE_distinguished n₁ X)).symm

Goal state after:
Module: Mathlib.CategoryTheory.Triangulated.TStructure.TruncLTGE

Goal state before:
pp: case pos
C : Type u
inst✝⁶ : Category.{v, u} C
inst✝⁵ : Preadditive C
inst✝⁴ : HasZeroObject C
inst✝³ : HasShift C ℤ
inst✝² : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝¹ : Pretriangulated C
t : TStructure C
inst✝ : IsTriangulated C
a b : ℤ
X : C
h : a ≤ b
⊢ IsIso ((t.truncGELTToLTGE a b).app X)

Tactic:
let u₁₂ := (t.natTransTruncLTOfLE a b h).app X
    let u₂₃ : (t.truncLT b).obj X ⟶ X := (t.truncLTι b).app X
    let u₁₃ : _ ⟶ X := (t.truncLTι a).app X
    have eq : u₁₂ ≫ u₂₃ = u₁₃ := by simp [u₁₂, u₂₃, u₁₃]
    have H := someOctahedron eq (t.triangleLTLTGELT_distinguished a b h X)
      (t.triangleLTGE_distinguished b X) (t.triangleLTGE_distinguished a X)
    let m₁ : (t.truncGELT a b).obj X ⟶ _ := H.m₁
    have : IsIso ((t.truncLT b).map H.m₁) :=
      t.isIso₁_truncLT_map_of_isGE _ H.mem b (by dsimp; infer_instance)
    have eq' : t.liftTruncLT m₁ (b - 1) b (by lia) = (t.truncGELTToLTGE a b).app X :=
      t.to_truncLT_obj_ext
        (by dsimp; exact t.from_truncGE_obj_ext (by simpa using H.comm₁))
    rw [← eq']
    have fac : (t.truncLTι b).app ((t.truncGE a).obj ((t.truncLT b).obj X)) ≫
        t.liftTruncLT m₁ (b - 1) b (by lia) = (t.truncLT b).map m₁ :=
      t.to_truncLT_obj_ext (by simp [truncGELT])
    exact IsIso.of_isIso_fac_left fac

Goal state after:
Module: Mathlib.Algebra.Homology.Factorizations.CM5a

Goal state before:
pp: case inr.refine_1
C : Type u_1
inst✝² : Category.{v_1, u_1} C
inst✝¹ : Abelian C
K L : CochainComplex C ℤ
inst✝ : EnoughInjectives C
n₁ i : ℤ
hn₁ : i + 1 = n₁
hi : i ≤ i
this : homologyMap biprod.inl i = 0
⊢ homologyMap (π K L n₁) i ≫ homologyMap (σ K L n₁) i = 𝟙 (homology (mid K L n₁) i)

Tactic:
simp [← homologyMap_id, ← biprod.total, homologyMap_comp, this]

Goal state after:
Module: Mathlib.Algebra.Homology.Factorizations.CM5a

Goal state before:
pp: C : Type u_1
inst✝² : Category.{v_1, u_1} C
inst✝¹ : Abelian C
K L : CochainComplex C ℤ
f : K ⟶ L
inst✝ : EnoughInjectives C
n₀ n₁ : ℤ
hn₁ : n₀ + 1 = n₁
hf : ∀ i ≤ n₀, QuasiIsoAt f i
i : ℤ
hi : i ≤ n₀
⊢ QuasiIsoAt (ι f n₁) i

Tactic:
have := quasiIsoAt_π K L n₀ n₁ hn₁ i hi

Goal state after:
C : Type u_1
inst✝² : Category.{v_1, u_1} C
inst✝¹ : Abelian C
K L : CochainComplex C ℤ
f : K ⟶ L
inst✝ : EnoughInjectives C
n₀ n₁ : ℤ
hn₁ : n₀ + 1 = n₁
hf : ∀ i ≤ n₀, QuasiIsoAt f i
i : ℤ
hi : i ≤ n₀
this : QuasiIsoAt (π K L n₁) i
⊢ QuasiIsoAt (ι f n₁) i
Module: Mathlib.AlgebraicTopology.ModelCategory.FibrantObjectHomotopy

Goal state before:
pp: C : Type u_1
inst✝¹ : Category.{v_1, u_1} C
inst✝ : ModelCategory C
⊢ (toHoCatLocalizerMorphism C).IsLocalizedEquivalence

Tactic:
by
  apply (factorsThroughLocalization C).isLocalizedEquivalence
  apply MorphismProperty.eq_inverseImage_quotientFunctor

Goal state after:
Module: Mathlib.CategoryTheory.Localization.Resolution

Goal state before:
pp: C₁ : Type u_1
C₂ : Type u_2
D₁ : Type u_3
D₂ : Type u_4
inst✝⁸ : Category.{v_1, u_1} C₁
inst✝⁷ : Category.{v_2, u_2} C₂
inst✝⁶ : Category.{v_3, u_3} D₁
inst✝⁵ : Category.{v_4, u_4} D₂
W₁ : MorphismProperty C₁
W₂ : MorphismProperty C₂
W₁' : MorphismProperty D₁
W₂' : MorphismProperty D₂
T : LocalizerMorphism W₁ W₂
L : LocalizerMorphism W₁ W₁'
R : LocalizerMorphism W₂ W₂'
B : LocalizerMorphism W₁' W₂'
inst✝⁴ : L.functor.EssSurj
inst✝³ : R.functor.Full
inst✝² : R.IsInduced
inst✝¹ : W₂'.RespectsIso
iso : T.functor ⋙ R.functor ≅ L.functor ⋙ B.functor
inst✝ : B.HasRightResolutions
⊢ T.HasRightResolutions

Tactic:
intro X₂
  let ρ : B.RightResolution (R.functor.obj X₂) := Classical.arbitrary _
  obtain ⟨X₁, ⟨e⟩⟩ := Functor.EssSurj.mem_essImage L.functor ρ.X₁
  exact ⟨{
    X₁ := X₁
    w := R.functor.preimage (ρ.w ≫ B.functor.map e.inv ≫ iso.inv.app X₁)
    hw := by
      simp only [← R.inverseImage_eq, MorphismProperty.inverseImage_iff, Functor.map_preimage]
      refine (W₂'.arrow_mk_iso_iff ?_).2 ρ.hw
      exact Arrow.isoMk (Iso.refl _) (iso.app _ ≪≫ B.functor.mapIso e)}⟩

Goal state after:
Module: Mathlib.CategoryTheory.GuitartExact.Basic

Goal state before:
pp: C₁ : Type u₁
C₂ : Type u₂
C₃ : Type u₃
C₄ : Type u₄
inst✝³ : Category.{v₁, u₁} C₁
inst✝² : Category.{v₂, u₂} C₂
inst✝¹ : Category.{v₃, u₃} C₃
inst✝ : Category.{v₄, u₄} C₄
T : C₁ ⥤ C₂
L : C₁ ⥤ C₃
R : C₂ ⥤ C₄
B : C₃ ⥤ C₄
w : TwoSquare T L R B
X₂ : C₂
X₃ : C₃
g : R.obj X₂ ⟶ B.obj X₃
X₁ : C₁
a : X₂ ⟶ T.obj X₁
b : ((w.structuredArrowDownwards X₂).obj (StructuredArrow.mk a)).right ⟶ (StructuredArrow.mk g).right
hb : ((w.structuredArrowDownwards X₂).obj (StructuredArrow.mk a)).hom ≫ B.map b = (StructuredArrow.mk g).hom
⊢ ∃ X₁_1 a_1 b_1,
    ∃ (comm : R.map a_1 ≫ w.app X₁_1 ≫ B.map b_1 = g),
      CostructuredArrow.mk (StructuredArrow.homMk b hb) = mk w g X₁_1 a_1 b_1 comm

Tactic:
exact ⟨X₁, a, b, by simpa using hb, rfl⟩

Goal state after:
Module: Mathlib.CategoryTheory.GuitartExact.Basic

Goal state before:
pp: C₁ : Type u₁
C₂ : Type u₂
C₃ : Type u₃
C₄ : Type u₄
inst✝³ : Category.{v₁, u₁} C₁
inst✝² : Category.{v₂, u₂} C₂
inst✝¹ : Category.{v₃, u₃} C₃
inst✝ : Category.{v₄, u₄} C₄
T : C₁ ⥤ C₂
L : C₁ ⥤ C₃
R : C₂ ⥤ C₄
B : C₃ ⥤ C₄
w : TwoSquare T L R B
hw : ∀ {X₂ : C₂} {X₃ : C₃} (g : R.obj X₂ ⟶ B.obj X₃), IsConnected (w.StructuredArrowRightwards g)
X₃ : C₃
g : CostructuredArrow R (B.obj X₃)
⊢ IsConnected (StructuredArrow g (w.costructuredArrowRightwards X₃))

Tactic:
apply hw

Goal state after:
Module: Mathlib.CategoryTheory.GuitartExact.Basic

Goal state before:
pp: C₁ : Type u₁
C₂ : Type u₂
C₃ : Type u₃
C₄ : Type u₄
inst✝³ : Category.{v₁, u₁} C₁
inst✝² : Category.{v₂, u₂} C₂
inst✝¹ : Category.{v₃, u₃} C₃
inst✝ : Category.{v₄, u₄} C₄
T : C₁ ⥤ C₂
L : C₁ ⥤ C₃
R : C₂ ⥤ C₄
B : C₃ ⥤ C₄
w : TwoSquare T L R B
hw : w.GuitartExact
X₃ : C₃
g : CostructuredArrow R (B.obj X₃)
⊢ IsConnected (StructuredArrow g (w.costructuredArrowRightwards X₃))

Tactic:
by
  rw [guitartExact_iff_isConnected_rightwards] at hw
  apply hw

Goal state after: