mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.RingTheory.Kaehler.Basic

Goal state before:
pp: case mp
R : Type u
S : Type v
inst✝² : CommRing R
inst✝¹ : CommRing S
inst✝ : Algebra R S
f : S →ₐ[R] S ⊗[R] S ⧸ ideal R S ^ 2
x : S
e₁ :
  (TensorProduct.lmul' R).kerSquareLift (f x) =
    (quotientCotangentIdealRingEquiv R S) ((Ideal.Quotient.mk (ideal R S).cotangentIdeal) (f x))
e₂ :
  x =
    (quotientCotangentIdealRingEquiv R S)
      ((IsScalarTower.toAlgHom R S ((S ⊗[R] S ⧸ ideal R S ^ 2) ⧸ (ideal R S).cotangentIdeal)) x)
⊢ ((Ideal.Quotient.mkₐ R (ideal R S).cotangentIdeal).comp f) x =
      (IsScalarTower.toAlgHom R S ((S ⊗[R] S ⧸ ideal R S ^ 2) ⧸ (ideal R S).cotangentIdeal)) x →
    ((TensorProduct.lmul' R).kerSquareLift.comp f) x = (AlgHom.id R S) x

pp: case mpr
R : Type u
S : Type v
inst✝² : CommRing R
inst✝¹ : CommRing S
inst✝ : Algebra R S
f : S →ₐ[R] S ⊗[R] S ⧸ ideal R S ^ 2
x : S
e₁ :
  (TensorProduct.lmul' R).kerSquareLift (f x) =
    (quotientCotangentIdealRingEquiv R S) ((Ideal.Quotient.mk (ideal R S).cotangentIdeal) (f x))
e₂ :
  x =
    (quotientCotangentIdealRingEquiv R S)
      ((IsScalarTower.toAlgHom R S ((S ⊗[R] S ⧸ ideal R S ^ 2) ⧸ (ideal R S).cotangentIdeal)) x)
⊢ ((TensorProduct.lmul' R).kerSquareLift.comp f) x = (AlgHom.id R S) x →
    ((Ideal.Quotient.mkₐ R (ideal R S).cotangentIdeal).comp f) x =
      (IsScalarTower.toAlgHom R S ((S ⊗[R] S ⧸ ideal R S ^ 2) ⧸ (ideal R S).cotangentIdeal)) x

Tactic:
· intro e
    exact (e₁.trans (@RingEquiv.congr_arg _ _ _ _ _ _
      (KaehlerDifferential.quotientCotangentIdealRingEquiv R S) _ _ e)).trans e₂.symm

Goal state after:
case mpr
R : Type u
S : Type v
inst✝² : CommRing R
inst✝¹ : CommRing S
inst✝ : Algebra R S
f : S →ₐ[R] S ⊗[R] S ⧸ ideal R S ^ 2
x : S
e₁ :
  (TensorProduct.lmul' R).kerSquareLift (f x) =
    (quotientCotangentIdealRingEquiv R S) ((Ideal.Quotient.mk (ideal R S).cotangentIdeal) (f x))
e₂ :
  x =
    (quotientCotangentIdealRingEquiv R S)
      ((IsScalarTower.toAlgHom R S ((S ⊗[R] S ⧸ ideal R S ^ 2) ⧸ (ideal R S).cotangentIdeal)) x)
⊢ ((TensorProduct.lmul' R).kerSquareLift.comp f) x = (AlgHom.id R S) x →
    ((Ideal.Quotient.mkₐ R (ideal R S).cotangentIdeal).comp f) x =
      (IsScalarTower.toAlgHom R S ((S ⊗[R] S ⧸ ideal R S ^ 2) ⧸ (ideal R S).cotangentIdeal)) x
Module: Mathlib.Algebra.Homology.ShortComplex.HomologicalComplex

Goal state before:
pp: C : Type u_1
inst✝¹ : Category.{v_1, u_1} C
inst✝ : HasZeroMorphisms C
ι : Type u_2
c : ComplexShape ι
K : HomologicalComplex C c
hK : IsZero K
i : ι
⊢ K.ExactAt i

Tactic:
apply ShortComplex.exact_of_isZero_X₂

Goal state after:
C : Type u_1
inst✝¹ : Category.{v_1, u_1} C
inst✝ : HasZeroMorphisms C
ι : Type u_2
c : ComplexShape ι
K : HomologicalComplex C c
hK : IsZero K
i : ι
⊢ IsZero (K.sc i).X₂
Module: Mathlib.Algebra.Homology.Homotopy

Goal state before:
pp: ι : Type u_1
V : Type u
inst✝¹ : Category.{v, u} V
inst✝ : Preadditive V
c : ComplexShape ι
C D : HomologicalComplex V c
f : (i j : ι) → C.X i ⟶ D.X j
i i' : ι
w : c.Rel i i'
⊢ (dNext i) f = C.d i i' ≫ f i' i

Tactic:
obtain rfl := c.next_eq' w

Goal state after:
ι : Type u_1
V : Type u
inst✝¹ : Category.{v, u} V
inst✝ : Preadditive V
c : ComplexShape ι
C D : HomologicalComplex V c
f : (i j : ι) → C.X i ⟶ D.X j
i : ι
w : c.Rel i (c.next i)
⊢ (dNext i) f = C.d i (c.next i) ≫ f (c.next i) i
Module: Mathlib.Algebra.Homology.HomotopyCategory.HomComplex

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
F G : CochainComplex C ℤ
ψ : (p : ℤ) → F.X p ⟶ G.X p
p : ℤ
⊢ (ofHoms ψ).v p p ⋯ = ψ p

Tactic:
by
  simp only [ofHoms, mk_v, eqToHom_refl, comp_id]

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

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
F G : CochainComplex C ℤ
φ : F ⟶ G
p : ℤ
⊢ (ofHom φ).v p p ⋯ = φ.f p

Tactic:
simp only [ofHom, ofHoms_v]

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

Goal state before:
pp: C : Type u
inst✝³ : Category.{v, u} C
inst✝² : Preadditive C
R : Type u_1
inst✝¹ : Ring R
inst✝ : Linear R C
F G K : CochainComplex C ℤ
n₁ n₂ n₁₂ : ℤ
z₁ : Cochain F G n₁
k : R
z₂ : Cochain G K n₂
h : n₁ + n₂ = n₁₂
⊢ z₁.comp (k • z₂) h = k • z₁.comp z₂ h

Tactic:
by
  ext p q hpq
  simp only [comp_v _ _ h p _ q rfl (by lia), smul_v, Linear.comp_smul]

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

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
F G : CochainComplex C ℤ
n₀ n₁ n₂ : ℤ
z : Cochain F G n₀
⊢ δ n₁ n₂ (δ n₀ n₁ z) = 0

Tactic:
by_cases h₁₂ : n₁ + 1 = n₂; swap
  · rw [δ_shape _ _ h₁₂]
  by_cases h₀₁ : n₀ + 1 = n₁; swap
  · rw [δ_shape _ _ h₀₁, δ_zero]
  ext p q hpq
  dsimp
  simp only [δ_v n₁ n₂ h₁₂ _ p q hpq _ _ rfl rfl,
    δ_v n₀ n₁ h₀₁ z p (q - 1) (by lia) (q - 2) _ (by lia) rfl,
    δ_v n₀ n₁ h₀₁ z (p + 1) q (by lia) _ (p + 2) rfl (by lia),
    ← h₁₂, Int.negOnePow_succ, add_comp, assoc,
    HomologicalComplex.d_comp_d, comp_zero, zero_add, comp_add,
    HomologicalComplex.d_comp_d_assoc, zero_comp, smul_zero,
    add_zero, add_neg_cancel, Units.neg_smul,
    Linear.units_smul_comp, Linear.comp_units_smul]

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

Goal state before:
pp: C : Type u
inst✝³ : Category.{v, u} C
inst✝² : Preadditive C
R : Type u_1
inst✝¹ : Ring R
inst✝ : Linear R C
F G K L : CochainComplex C ℤ
n m : ℤ
z : Cochain F G (-1)
i j : ℤ
hij : (ComplexShape.up ℤ).Rel j i
⊢ i + -1 = j

Tactic:
by dsimp at hij; rw [← hij, add_neg_cancel_right]

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

Goal state before:
pp: case pos
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
F G K : CochainComplex C ℤ
n : ℤ
z₁ : Cocycle F G 0
z₂ : Cochain G K n
m : ℤ
hnm : n + 1 = m
⊢ δ n m ((↑z₁).comp z₂ ⋯) = (↑z₁).comp (δ n m z₂) ⋯

Tactic:
simp [δ_zero_cochain_comp _ _ _ hnm]

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

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
F G : CochainComplex C ℤ
f₁ f₂ : F ⟶ G
h : ofHom f₁ = ofHom f₂
⊢ (Cocycle.equivHom F G) f₁ = (Cocycle.equivHom F G) f₂

Tactic:
ext1

Goal state after:
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
F G : CochainComplex C ℤ
f₁ f₂ : F ⟶ G
h : ofHom f₁ = ofHom f₂
⊢ ↑((Cocycle.equivHom F G) f₁) = ↑((Cocycle.equivHom F G) f₂)
Module: Mathlib.CategoryTheory.Quotient.Linear

Goal state before:
pp: R : Type u_1
C : Type u_2
inst✝⁶ : Semiring R
inst✝⁵ : Category.{v_1, u_2} C
inst✝⁴ : Preadditive C
inst✝³ : Linear R C
r : HomRel C
inst✝² : Congruence r
hr : ∀ (a : R) ⦃X Y : C⦄ (f₁ f₂ : X ⟶ Y), r f₁ f₂ → r (a • f₁) (a • f₂)
inst✝¹ : Preadditive (Quotient r)
inst✝ : (functor r).Additive
X Y : C
smul : SMul R ((functor r).obj X ⟶ (functor r).obj Y) := Linear.smul r hr ((functor r).obj X) ((functor r).obj Y)
a b : R
f : X ⟶ Y
⊢ (functor r).map ((a + b) • f) = (functor r).map (a • f) + (functor r).map (b • f)

Tactic:
add_smul,

Goal state after:
R : Type u_1
C : Type u_2
inst✝⁶ : Semiring R
inst✝⁵ : Category.{v_1, u_2} C
inst✝⁴ : Preadditive C
inst✝³ : Linear R C
r : HomRel C
inst✝² : Congruence r
hr : ∀ (a : R) ⦃X Y : C⦄ (f₁ f₂ : X ⟶ Y), r f₁ f₂ → r (a • f₁) (a • f₂)
inst✝¹ : Preadditive (Quotient r)
inst✝ : (functor r).Additive
X Y : C
smul : SMul R ((functor r).obj X ⟶ (functor r).obj Y) := Linear.smul r hr ((functor r).obj X) ((functor r).obj Y)
a b : R
f : X ⟶ Y
⊢ (functor r).map (a • f + b • f) = (functor r).map (a • f) + (functor r).map (b • f)
Module: Mathlib.CategoryTheory.Shift.Quotient

Goal state before:
pp: C : Type u
inst✝⁶ : Category.{v, u} C
D : Type u'
inst✝⁵ : Category.{v', u'} D
F : C ⥤ D
r : HomRel C
A : Type w
inst✝⁴ : AddMonoid A
inst✝³ : HasShift C A
inst✝² : HasShift D A
inst✝¹ : r.IsCompatibleWithShift A
inst✝ : F.CommShift A
hF : ∀ (x y : C) (f₁ f₂ : x ⟶ y), r f₁ f₂ → F.map f₁ = F.map f₂
⊢ LiftCommShift.iso F r hF 0 = Functor.CommShift.isoZero (lift r F hF) A

Tactic:
ext1

Goal state after:
C : Type u
inst✝⁶ : Category.{v, u} C
D : Type u'
inst✝⁵ : Category.{v', u'} D
F : C ⥤ D
r : HomRel C
A : Type w
inst✝⁴ : AddMonoid A
inst✝³ : HasShift C A
inst✝² : HasShift D A
inst✝¹ : r.IsCompatibleWithShift A
inst✝ : F.CommShift A
hF : ∀ (x y : C) (f₁ f₂ : x ⟶ y), r f₁ f₂ → F.map f₁ = F.map f₂
⊢ (LiftCommShift.iso F r hF 0).hom = (Functor.CommShift.isoZero (lift r F hF) A).hom
Module: Mathlib.CategoryTheory.Shift.Quotient

Goal state before:
pp: C : Type u
inst✝⁶ : Category.{v, u} C
D : Type u'
inst✝⁵ : Category.{v', u'} D
F : C ⥤ D
r : HomRel C
A : Type w
inst✝⁴ : AddMonoid A
inst✝³ : HasShift C A
inst✝² : HasShift D A
inst✝¹ : r.IsCompatibleWithShift A
inst✝ : F.CommShift A
hF : ∀ (x y : C) (f₁ f₂ : x ⟶ y), r f₁ f₂ → F.map f₁ = F.map f₂
a b : A
⊢ LiftCommShift.iso F r hF (a + b) = Functor.CommShift.isoAdd (LiftCommShift.iso F r hF a) (LiftCommShift.iso F r hF b)

Tactic:
ext1

Goal state after:
C : Type u
inst✝⁶ : Category.{v, u} C
D : Type u'
inst✝⁵ : Category.{v', u'} D
F : C ⥤ D
r : HomRel C
A : Type w
inst✝⁴ : AddMonoid A
inst✝³ : HasShift C A
inst✝² : HasShift D A
inst✝¹ : r.IsCompatibleWithShift A
inst✝ : F.CommShift A
hF : ∀ (x y : C) (f₁ f₂ : x ⟶ y), r f₁ f₂ → F.map f₁ = F.map f₂
a b : A
⊢ (LiftCommShift.iso F r hF (a + b)).hom =
    (Functor.CommShift.isoAdd (LiftCommShift.iso F r hF a) (LiftCommShift.iso F r hF b)).hom
Module: Mathlib.CategoryTheory.Shift.Quotient

Goal state before:
pp: C : Type u
inst✝⁶ : Category.{v, u} C
D : Type u'
inst✝⁵ : Category.{v', u'} D
F : C ⥤ D
r : HomRel C
A : Type w
inst✝⁴ : AddMonoid A
inst✝³ : HasShift C A
inst✝² : HasShift D A
inst✝¹ : r.IsCompatibleWithShift A
inst✝ : F.CommShift A
hF : ∀ (x y : C) (f₁ f₂ : x ⟶ y), r f₁ f₂ → F.map f₁ = F.map f₂
a : A
X : C
⊢ ((lift r F hF).map (𝟙 ((shiftFunctor C a ⋙ functor r).obj X)) ≫ (Functor.commShiftIso F a).hom.app X) ≫
      (shiftFunctor D a).map (𝟙 (F.obj X)) =
    𝟙 (F.obj ((shiftFunctor C a).obj X)) ≫ (Functor.commShiftIso F a).hom.app X

Tactic:
simp [lift, Quotient.functor]

Goal state after:
Module: Mathlib.CategoryTheory.Shift.CommShift

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
F : C ⥤ D
A : Type u_4
inst✝³ : AddMonoid A
inst✝² : HasShift C A
inst✝¹ : HasShift D A
inst✝ : F.CommShift A
X : C
a b : A
h : a + b = 0
eq :
  F.map ((shiftFunctorZero C A).hom.app X) ≫ (shiftFunctorZero D A).inv.app (F.obj X) =
    F.map ((shiftFunctorAdd' C a b 0 h).hom.app X) ≫
      (commShiftIso F b).hom.app ((shiftFunctor C a).obj X) ≫
        (shiftFunctor D b).map ((commShiftIso F a).hom.app X) ≫ (shiftFunctorAdd' D a b 0 h).inv.app (F.obj X)
⊢ F.map ((shiftFunctorAdd' C a b 0 h).hom.app X) ≫
      F.map ((shiftFunctorAdd' C a b 0 h).inv.app X ≫ (shiftFunctorZero C A).hom.app X) =
    F.map ((shiftFunctorAdd' C a b 0 h).hom.app X) ≫
      (commShiftIso F b).hom.app ((shiftFunctor C a).obj X) ≫
        (shiftFunctor D b).map ((commShiftIso F a).hom.app X) ≫
          (shiftFunctorAdd' D a b 0 h).inv.app (F.obj X) ≫ (shiftFunctorZero D A).hom.app (F.obj X)

Tactic:
← reassoc_of% eq,

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
F : C ⥤ D
A : Type u_4
inst✝³ : AddMonoid A
inst✝² : HasShift C A
inst✝¹ : HasShift D A
inst✝ : F.CommShift A
X : C
a b : A
h : a + b = 0
eq :
  F.map ((shiftFunctorZero C A).hom.app X) ≫ (shiftFunctorZero D A).inv.app (F.obj X) =
    F.map ((shiftFunctorAdd' C a b 0 h).hom.app X) ≫
      (commShiftIso F b).hom.app ((shiftFunctor C a).obj X) ≫
        (shiftFunctor D b).map ((commShiftIso F a).hom.app X) ≫ (shiftFunctorAdd' D a b 0 h).inv.app (F.obj X)
⊢ F.map ((shiftFunctorAdd' C a b 0 h).hom.app X) ≫
      F.map ((shiftFunctorAdd' C a b 0 h).inv.app X ≫ (shiftFunctorZero C A).hom.app X) =
    F.map ((shiftFunctorZero C A).hom.app X) ≫
      (shiftFunctorZero D A).inv.app (F.obj X) ≫ (shiftFunctorZero D A).hom.app (F.obj X)
Module: Mathlib.CategoryTheory.Triangulated.Basic

Goal state before:
pp: C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : HasShift C ℤ
T₁ T₂ T₃ : Triangle C
J : Type u_1
T : J → Triangle C
inst✝³ : HasProduct fun j ↦ (T j).obj₁
inst✝² : HasProduct fun j ↦ (T j).obj₂
inst✝¹ : HasProduct fun j ↦ (T j).obj₃
inst✝ : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₁
s : Fan T
m : s.pt ⟶ (fan T).pt
hm : ∀ (j : J), m ≫ (fan T).proj j = s.proj j
⊢ m = lift T s.proj

Tactic:
ext1

Goal state after:
case h₁
C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : HasShift C ℤ
T₁ T₂ T₃ : Triangle C
J : Type u_1
T : J → Triangle C
inst✝³ : HasProduct fun j ↦ (T j).obj₁
inst✝² : HasProduct fun j ↦ (T j).obj₂
inst✝¹ : HasProduct fun j ↦ (T j).obj₃
inst✝ : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₁
s : Fan T
m : s.pt ⟶ (fan T).pt
hm : ∀ (j : J), m ≫ (fan T).proj j = s.proj j
⊢ m.hom₁ = (lift T s.proj).hom₁

case h₂
C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : HasShift C ℤ
T₁ T₂ T₃ : Triangle C
J : Type u_1
T : J → Triangle C
inst✝³ : HasProduct fun j ↦ (T j).obj₁
inst✝² : HasProduct fun j ↦ (T j).obj₂
inst✝¹ : HasProduct fun j ↦ (T j).obj₃
inst✝ : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₁
s : Fan T
m : s.pt ⟶ (fan T).pt
hm : ∀ (j : J), m ≫ (fan T).proj j = s.proj j
⊢ m.hom₂ = (lift T s.proj).hom₂

case h₃
C : Type u
inst✝⁵ : Category.{v, u} C
inst✝⁴ : HasShift C ℤ
T₁ T₂ T₃ : Triangle C
J : Type u_1
T : J → Triangle C
inst✝³ : HasProduct fun j ↦ (T j).obj₁
inst✝² : HasProduct fun j ↦ (T j).obj₂
inst✝¹ : HasProduct fun j ↦ (T j).obj₃
inst✝ : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₁
s : Fan T
m : s.pt ⟶ (fan T).pt
hm : ∀ (j : J), m ≫ (fan T).proj j = s.proj j
⊢ m.hom₃ = (lift T s.proj).hom₃
Module: Mathlib.CategoryTheory.Triangulated.TriangleShift

Goal state before:
pp: C : Type u
inst✝³ : Category.{v, u} C
inst✝² : Preadditive C
inst✝¹ : HasShift C ℤ
inst✝ : ∀ (n : ℤ), (CategoryTheory.shiftFunctor C n).Additive
n : ℤ
X✝ Y✝ : Triangle C
f : X✝ ⟶ Y✝
⊢ (mk (n.negOnePow • (CategoryTheory.shiftFunctor C n).map X✝.mor₁)
          (n.negOnePow • (CategoryTheory.shiftFunctor C n).map X✝.mor₂)
          (n.negOnePow •
            (CategoryTheory.shiftFunctor C n).map X✝.mor₃ ≫ (shiftFunctorComm C 1 n).hom.app X✝.obj₁)).mor₃ ≫
      (CategoryTheory.shiftFunctor C 1).map ((CategoryTheory.shiftFunctor C n).map f.hom₁) =
    (CategoryTheory.shiftFunctor C n).map f.hom₃ ≫
      (mk (n.negOnePow • (CategoryTheory.shiftFunctor C n).map Y✝.mor₁)
          (n.negOnePow • (CategoryTheory.shiftFunctor C n).map Y✝.mor₂)
          (n.negOnePow • (CategoryTheory.shiftFunctor C n).map Y✝.mor₃ ≫ (shiftFunctorComm C 1 n).hom.app Y✝.obj₁)).mor₃

Tactic:
by
        dsimp
        rw [Linear.units_smul_comp, Linear.comp_units_smul, ← Functor.map_comp_assoc, ← f.comm₃,
          Functor.map_comp, assoc, assoc, dsimp% (shiftFunctorComm C 1 n).hom.naturality]

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

Goal state before:
pp: C : Type u
inst✝² : Category.{v, u} C
inst✝¹ : HasShift C ℤ
T₁ T₂ T₃ : Triangle C
J : Type u_1
inst✝ : Category.{v_1, u_1} J
A B : J ⥤ Triangle C
iso₁ : A ⋙ π₁ ≅ B ⋙ π₁
iso₂ : A ⋙ π₂ ≅ B ⋙ π₂
iso₃ : A ⋙ π₃ ≅ B ⋙ π₃
comm₁ : A.whiskerLeft π₁Toπ₂ ≫ iso₂.hom = iso₁.hom ≫ B.whiskerLeft π₁Toπ₂
comm₂ : A.whiskerLeft π₂Toπ₃ ≫ iso₃.hom = iso₂.hom ≫ B.whiskerLeft π₂Toπ₃
comm₃ : A.whiskerLeft π₃Toπ₁ ≫ whiskerRight iso₁.hom (shiftFunctor C 1) = iso₃.hom ≫ B.whiskerLeft π₃Toπ₁
⊢ A.whiskerLeft π₃Toπ₁ ≫ 𝟙 ((A ⋙ π₁) ⋙ shiftFunctor C 1) = A.whiskerLeft π₃Toπ₁

Tactic:
apply comp_id

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

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
K L : CochainComplex C ℤ
n : ℤ
f : K ⟶ (CategoryTheory.shiftFunctor (CochainComplex C ℤ) n).obj L
L' : CochainComplex C ℤ
g : L ⟶ L'
⊢ equivHomShift (f ≫ (CategoryTheory.shiftFunctor (CochainComplex C ℤ) n).map g) = (equivHomShift f).postcomp g

Tactic:
by
  ext p q rfl
  simp [equivHomShift_apply, Cochain.rightUnshift_v _ _ _ _ _ _ _ (add_zero p)]

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

Goal state before:
pp: C : Type u_1
inst✝² : Category.{v_1, u_1} C
inst✝¹ : Preadditive C
inst✝ : HasBinaryBiproducts C
K₁ L₁ K₂ L₂ : CochainComplex C ℤ
φ₁ : K₁ ⟶ L₁
φ₂ : K₂ ⟶ L₂
a : K₁ ⟶ K₂
b : L₁ ⟶ L₂
H : Homotopy (φ₁ ≫ b) (a ≫ φ₂)
p : ℤ
⊢ (desc φ₁
            ((Cochain.ofHom a).comp (inl φ₂) mapOfHomotopy._proof_2 +
              (Cochain.ofHomotopy H).comp (Cochain.ofHom (inr φ₂)) mapOfHomotopy._proof_3)
            (b ≫ inr φ₂) ⋯).f
        p ≫
      ((-↑(fst φ₂)).rightShift 1 0 triangle._proof_3).v p p ⋯ =
    ((-↑(fst φ₁)).rightShift 1 0 triangle._proof_3).v p p ⋯ ≫ a.f (p + 1)

Tactic:
simp only [Int.reduceNeg, Cochain.rightShift_neg, Cochain.neg_v, shiftFunctor_obj_X',
    Cochain.rightShift_v _ 1 0 _ p p _ (p + 1) rfl, shiftFunctor_obj_X, shiftFunctorObjXIso,
    HomologicalComplex.XIsoOfEq_rfl, Iso.refl_inv, comp_id, Preadditive.comp_neg,
    Preadditive.neg_comp, ext_from_iff _ _ _ rfl, inl_v_desc_f_assoc, Cochain.add_v,
    Cochain.zero_cochain_comp_v, Cochain.ofHom_v, Cochain.comp_zero_cochain_v, Preadditive.add_comp,
    assoc, inl_v_fst_v, inr_f_fst_v, comp_zero, add_zero, inl_v_fst_v_assoc, inr_f_desc_f_assoc,
    HomologicalComplex.comp_f, neg_zero, inr_f_fst_v_assoc, zero_comp, and_self]

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

Goal state before:
pp: case refine_1
C : Type u
inst✝⁸ : Category.{v, u} C
inst✝⁷ : HasZeroObject C
inst✝⁶ : HasShift C ℤ
inst✝⁵ : Preadditive C
inst✝⁴ : ∀ (n : ℤ), (shiftFunctor C n).Additive
hC : Pretriangulated C
J : Type u_1
T : J → Triangle C
hT : ∀ (j : J), T j ∈ distinguishedTriangles
inst✝³ : HasProduct fun j ↦ (T j).obj₁
inst✝² : HasProduct fun j ↦ (T j).obj₂
inst✝¹ : HasProduct fun j ↦ (T j).obj₃
inst✝ : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₁
f₁ : (∏ᶜ fun j ↦ (T j).obj₁) ⟶ ∏ᶜ fun j ↦ (T j).obj₂ := Limits.Pi.map fun j ↦ (T j).mor₁
Z : C
f₂ : (∏ᶜ fun j ↦ (T j).obj₂) ⟶ Z
f₃ : Z ⟶ (shiftFunctor C 1).obj (∏ᶜ fun j ↦ (T j).obj₁)
T' : Triangle C := Triangle.mk f₁ f₂ f₃
hT' : T' ∈ distinguishedTriangles
φ : (j : J) → T' ⟶ T j :=
  fun j ↦
    completeDistinguishedTriangleMorphism T' (T j) hT' ⋯ (Pi.π (fun j ↦ (T j).obj₁) j) (Pi.π (fun j ↦ (T j).obj₂) j) ⋯
φ' : T' ⟶ productTriangle T := productTriangle.lift T φ
h₁ : φ'.hom₁ = 𝟙 T'.obj₁
h₂ : φ'.hom₂ = 𝟙 T'.obj₂
this✝ : IsIso φ'.hom₁
this : IsIso φ'.hom₂
A✝ A : C
f : A ⟶ T'.obj₃
hf : f ≫ φ'.hom₃ = 0
hf' : f ≫ T'.mor₃ = 0
g : A ⟶ T'.obj₂
hg : f = g ≫ T'.mor₂
hg' : ∀ (j : J), (g ≫ Pi.π (fun j ↦ (T j).obj₂) j) ≫ (T j).mor₂ = 0
⊢ f = 0

Tactic:
have hg'' := fun j => (T j).coyoneda_exact₂ (hT j) _ (hg' j)

Goal state after:
case refine_1
C : Type u
inst✝⁸ : Category.{v, u} C
inst✝⁷ : HasZeroObject C
inst✝⁶ : HasShift C ℤ
inst✝⁵ : Preadditive C
inst✝⁴ : ∀ (n : ℤ), (shiftFunctor C n).Additive
hC : Pretriangulated C
J : Type u_1
T : J → Triangle C
hT : ∀ (j : J), T j ∈ distinguishedTriangles
inst✝³ : HasProduct fun j ↦ (T j).obj₁
inst✝² : HasProduct fun j ↦ (T j).obj₂
inst✝¹ : HasProduct fun j ↦ (T j).obj₃
inst✝ : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₁
f₁ : (∏ᶜ fun j ↦ (T j).obj₁) ⟶ ∏ᶜ fun j ↦ (T j).obj₂ := Limits.Pi.map fun j ↦ (T j).mor₁
Z : C
f₂ : (∏ᶜ fun j ↦ (T j).obj₂) ⟶ Z
f₃ : Z ⟶ (shiftFunctor C 1).obj (∏ᶜ fun j ↦ (T j).obj₁)
T' : Triangle C := Triangle.mk f₁ f₂ f₃
hT' : T' ∈ distinguishedTriangles
φ : (j : J) → T' ⟶ T j :=
  fun j ↦
    completeDistinguishedTriangleMorphism T' (T j) hT' ⋯ (Pi.π (fun j ↦ (T j).obj₁) j) (Pi.π (fun j ↦ (T j).obj₂) j) ⋯
φ' : T' ⟶ productTriangle T := productTriangle.lift T φ
h₁ : φ'.hom₁ = 𝟙 T'.obj₁
h₂ : φ'.hom₂ = 𝟙 T'.obj₂
this✝ : IsIso φ'.hom₁
this : IsIso φ'.hom₂
A✝ A : C
f : A ⟶ T'.obj₃
hf : f ≫ φ'.hom₃ = 0
hf' : f ≫ T'.mor₃ = 0
g : A ⟶ T'.obj₂
hg : f = g ≫ T'.mor₂
hg' : ∀ (j : J), (g ≫ Pi.π (fun j ↦ (T j).obj₂) j) ≫ (T j).mor₂ = 0
hg'' : ∀ (j : J), ∃ g_1, g ≫ Pi.π (fun j ↦ (T j).obj₂) j = g_1 ≫ (T j).mor₁
⊢ f = 0
Module: Mathlib.CategoryTheory.Triangulated.Pretriangulated

Goal state before:
pp: C : Type u
inst✝⁴ : Category.{v, u} C
inst✝³ : HasZeroObject C
inst✝² : HasShift C ℤ
inst✝¹ : Preadditive C
inst✝ : ∀ (n : ℤ), (shiftFunctor C n).Additive
hC : Pretriangulated C
T₁ T₂ : Triangle C
hT₁ : T₁ ∈ distinguishedTriangles
hT₂ : T₂ ∈ distinguishedTriangles
e : Arrow.mk T₁.mor₁ ≅ Arrow.mk T₂.mor₁
⊢ ∃ e', e'.hom.hom₁ = Arrow.Hom.left e.hom ∧ e'.hom.hom₂ = Arrow.Hom.right e.hom

Tactic:
let φ := completeDistinguishedTriangleMorphism T₁ T₂ hT₁ hT₂ e.hom.left e.hom.right e.hom.w.symm
  have : IsIso φ.hom₁ := by dsimp [φ]; infer_instance
  have : IsIso φ.hom₂ := by dsimp [φ]; infer_instance
  have : IsIso φ.hom₃ := isIso₃_of_isIso₁₂ φ hT₁ hT₂ inferInstance inferInstance
  have : IsIso φ := by
    apply Triangle.isIso_of_isIsos
    all_goals infer_instance
  exact ⟨asIso φ, by simp [φ], by simp [φ]⟩

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

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝¹⁵ : Category.{v_1, u_1} C
inst✝¹⁴ : Category.{v_2, u_2} D
inst✝¹³ : HasShift C ℤ
inst✝¹² : HasShift D ℤ
inst✝¹¹ : HasZeroObject C
inst✝¹⁰ : HasZeroObject D
inst✝⁹ : Preadditive C
inst✝⁸ : Preadditive D
inst✝⁷ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁶ : ∀ (n : ℤ), (shiftFunctor D n).Additive
inst✝⁵ : Pretriangulated C
inst✝⁴ : Pretriangulated D
F : C ⥤ D
inst✝³ : F.CommShift ℤ
inst✝² : F.IsTriangulated
inst✝¹ : (F.mapComposableArrows 2).EssSurj
inst✝ : IsTriangulated C
Y₁ Y₂ : D
⊢ ∀ {X₃ Z₁₂ Z₂₃ Z₁₃ : D} {u₁₂ : Y₁ ⟶ Y₂} {u₂₃ : Y₂ ⟶ X₃} {u₁₃ : Y₁ ⟶ X₃} (comm : u₁₂ ≫ u₂₃ = u₁₃) {v₁₂ : Y₂ ⟶ Z₁₂}
    {w₁₂ : Z₁₂ ⟶ (shiftFunctor D 1).obj Y₁} (h₁₂ : Triangle.mk u₁₂ v₁₂ w₁₂ ∈ distinguishedTriangles) {v₂₃ : X₃ ⟶ Z₂₃}
    {w₂₃ : Z₂₃ ⟶ (shiftFunctor D 1).obj Y₂} (h₂₃ : Triangle.mk u₂₃ v₂₃ w₂₃ ∈ distinguishedTriangles) {v₁₃ : X₃ ⟶ Z₁₃}
    {w₁₃ : Z₁₃ ⟶ (shiftFunctor D 1).obj Y₁} (h₁₃ : Triangle.mk u₁₃ v₁₃ w₁₃ ∈ distinguishedTriangles),
    Nonempty (Octahedron comm h₁₂ h₂₃ h₁₃)

Tactic:
Y₃

Goal state after:
C : Type u_1
D : Type u_2
inst✝¹⁵ : Category.{v_1, u_1} C
inst✝¹⁴ : Category.{v_2, u_2} D
inst✝¹³ : HasShift C ℤ
inst✝¹² : HasShift D ℤ
inst✝¹¹ : HasZeroObject C
inst✝¹⁰ : HasZeroObject D
inst✝⁹ : Preadditive C
inst✝⁸ : Preadditive D
inst✝⁷ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁶ : ∀ (n : ℤ), (shiftFunctor D n).Additive
inst✝⁵ : Pretriangulated C
inst✝⁴ : Pretriangulated D
F : C ⥤ D
inst✝³ : F.CommShift ℤ
inst✝² : F.IsTriangulated
inst✝¹ : (F.mapComposableArrows 2).EssSurj
inst✝ : IsTriangulated C
Y₁ Y₂ Y₃ : D
⊢ ∀ {Z₁₂ Z₂₃ Z₁₃ : D} {u₁₂ : Y₁ ⟶ Y₂} {u₂₃ : Y₂ ⟶ Y₃} {u₁₃ : Y₁ ⟶ Y₃} (comm : u₁₂ ≫ u₂₃ = u₁₃) {v₁₂ : Y₂ ⟶ Z₁₂}
    {w₁₂ : Z₁₂ ⟶ (shiftFunctor D 1).obj Y₁} (h₁₂ : Triangle.mk u₁₂ v₁₂ w₁₂ ∈ distinguishedTriangles) {v₂₃ : Y₃ ⟶ Z₂₃}
    {w₂₃ : Z₂₃ ⟶ (shiftFunctor D 1).obj Y₂} (h₂₃ : Triangle.mk u₂₃ v₂₃ w₂₃ ∈ distinguishedTriangles) {v₁₃ : Y₃ ⟶ Z₁₃}
    {w₁₃ : Z₁₃ ⟶ (shiftFunctor D 1).obj Y₁} (h₁₃ : Triangle.mk u₁₃ v₁₃ w₁₃ ∈ distinguishedTriangles),
    Nonempty (Octahedron comm h₁₂ h₂₃ h₁₃)
Module: Mathlib.CategoryTheory.Triangulated.Functor

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝¹⁶ : Category.{v_1, u_1} C
inst✝¹⁵ : Category.{v_2, u_2} D
inst✝¹⁴ : HasShift C ℤ
inst✝¹³ : HasShift D ℤ
inst✝¹² : HasZeroObject C
inst✝¹¹ : HasZeroObject D
inst✝¹⁰ : Preadditive C
inst✝⁹ : Preadditive D
inst✝⁸ : ∀ (n : ℤ), (shiftFunctor C n).Additive
inst✝⁷ : ∀ (n : ℤ), (shiftFunctor D n).Additive
inst✝⁶ : Pretriangulated C
inst✝⁵ : Pretriangulated D
F : C ⥤ D
inst✝⁴ : F.CommShift ℤ
inst✝³ : F.IsTriangulated
inst✝² : F.Full
inst✝¹ : F.Faithful
inst✝ : IsTriangulated D
X₁ X₂ X₃ Z₁₂ Z₂₃ Z₁₃ : C
u₁₂ : X₁ ⟶ X₂
u₂₃ : X₂ ⟶ X₃
u₁₃ : X₁ ⟶ X₃
comm : u₁₂ ≫ u₂₃ = u₁₃
v₁₂ : X₂ ⟶ Z₁₂
w₁₂ : Z₁₂ ⟶ (shiftFunctor C 1).obj X₁
h₁₂ : Triangle.mk u₁₂ v₁₂ w₁₂ ∈ distinguishedTriangles
v₂₃ : X₃ ⟶ Z₂₃
w₂₃ : Z₂₃ ⟶ (shiftFunctor C 1).obj X₂
h₂₃ : Triangle.mk u₂₃ v₂₃ w₂₃ ∈ distinguishedTriangles
v₁₃ : X₃ ⟶ Z₁₃
w₁₃ : Z₁₃ ⟶ (shiftFunctor C 1).obj X₁
h₁₃ : Triangle.mk u₁₃ v₁₃ w₁₃ ∈ distinguishedTriangles
comm' : F.map u₁₂ ≫ F.map u₂₃ = F.map u₁₃
H : Octahedron comm' ⋯ ⋯ ⋯ := someOctahedron comm' ⋯ ⋯ ⋯
⊢ F.map (v₁₃ ≫ F.preimage H.m₃) = F.map v₂₃

Tactic:
by simpa using H.comm₃

Goal state after: