mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Algebra.Homology.HomotopyCategory.MappingCone

Goal state before:
pp: C : Type u_1
inst✝² : Category.{v, u_1} C
inst✝¹ : Preadditive C
F G : CochainComplex C ℤ
φ : F ⟶ G
inst✝ : HasHomotopyCofiber φ
K : CochainComplex C ℤ
d e : ℤ
γ : Cochain F K d
he : 1 + d = e
hf : 0 + e = e
⊢ Cochain.comp 0 γ he = 0

Tactic:
Cochain.zero_comp

Goal state after:
C : Type u_1
inst✝² : Category.{v, u_1} C
inst✝¹ : Preadditive C
F G : CochainComplex C ℤ
φ : F ⟶ G
inst✝ : HasHomotopyCofiber φ
K : CochainComplex C ℤ
d e : ℤ
γ : Cochain F K d
he : 1 + d = e
hf : 0 + e = e
⊢ 0 = 0
Module: Mathlib.Algebra.Homology.Homotopy

Goal state before:
pp: V : Type u
inst✝¹ : Category.{v, u} V
inst✝ : Preadditive V
P Q : ChainComplex V ℕ
f : (i j : ℕ) → P.X i ⟶ Q.X j
i : ℕ
⊢ P.d (i + 1) ((ComplexShape.down ℕ).next (i + 1)) ≫ f ((ComplexShape.down ℕ).next (i + 1)) (i + 1) =
    P.d (i + 1) i ≫ f i (i + 1)

Tactic:
have : (ComplexShape.down ℕ).next (i + 1) = i := ChainComplex.next_nat_succ _

Goal state after:
V : Type u
inst✝¹ : Category.{v, u} V
inst✝ : Preadditive V
P Q : ChainComplex V ℕ
f : (i j : ℕ) → P.X i ⟶ Q.X j
i : ℕ
this : (ComplexShape.down ℕ).next (i + 1) = i
⊢ P.d (i + 1) ((ComplexShape.down ℕ).next (i + 1)) ≫ f ((ComplexShape.down ℕ).next (i + 1)) (i + 1) =
    P.d (i + 1) i ≫ f i (i + 1)
Module: Mathlib.Algebra.Homology.HomotopyCategory.MappingCone

Goal state before:
pp: C : Type u_1
inst✝² : Category.{v, u_1} C
inst✝¹ : Preadditive C
F G : CochainComplex C ℤ
φ : F ⟶ G
inst✝ : HasHomotopyCofiber φ
i j : ℤ
hij : i + 1 = j
K : CochainComplex C ℤ
γ₁ γ₂ : Cochain (mappingCone φ) K j
⊢ γ₁ = γ₂ ↔
    (inl φ).comp γ₁ ⋯ = (inl φ).comp γ₂ ⋯ ∧ (Cochain.ofHom (inr φ)).comp γ₁ ⋯ = (Cochain.ofHom (inr φ)).comp γ₂ ⋯

Tactic:
by
  constructor
  · rintro rfl
    tauto
  · rintro ⟨h₁, h₂⟩
    ext p q hpq
    rw [ext_from_iff φ (p + 1) p rfl]
    replace h₁ := Cochain.congr_v h₁ (p + 1) q (by lia)
    replace h₂ := Cochain.congr_v h₂ p q (by lia)
    simp only [Cochain.comp_v (inl φ) _ _ (p + 1) p q (by lia) hpq] at h₁
    simp only [Cochain.zero_cochain_comp_v, Cochain.ofHom_v] at h₂
    exact ⟨h₁, h₂⟩

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
K L : CochainComplex C ℤ
p n p' q' : ℤ
hp' : p' + 1 = p
p'' q'' : ℤ
hpq'' : p'' + (n + 1) = q''
f : K.X p ⟶ L.X q''
hq' : q'' + 1 = q'
h : p'' = p'
⊢ (n + 1).negOnePow • K.d p'' (p'' + 1) ≫ (single f n).v (p'' + 1) q'' ⋯ =
    (n + 1).negOnePow • (single (K.d p' p ≫ f) (n + 1)).v p'' q'' hpq''

Tactic:
subst h
        obtain rfl : p = p'' + 1 := by lia
        simp

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

Goal state before:
pp: ι : Type u_2
V : Type u
inst✝¹ : Category.{v, u} V
inst✝ : Preadditive V
c : ComplexShape ι
C : HomologicalComplex V c
⊢ IsZero ((quotient V c).obj C) ↔ Nonempty (Homotopy (𝟙 C) 0)

Tactic:
rw [IsZero.iff_id_eq_zero]
  constructor
  · intro h
    exact ⟨(homotopyOfEq _ _ (by simp [h]))⟩
  · rintro ⟨h⟩
    simpa using (eq_of_homotopy _ _ h)

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 M : CochainComplex C ℤ
n : ℤ
γ : Cochain K L n
m a : ℤ
γ' : Cochain L ((CategoryTheory.shiftFunctor (CochainComplex C ℤ) a).obj M) m
nm : ℤ
hnm : n + m = nm
nm' : ℤ
hnm' : nm + a = nm'
m' : ℤ
hm' : m + a = m'
p q : ℤ
hpq : p + nm' = q
⊢ (γ.v p (p + n) ⋯ ≫ γ'.v (p + n) (p + n + m) ⋯) ≫ (M.shiftFunctorObjXIso a (p + n + m) q ⋯).hom =
    γ.v p (p + n) ⋯ ≫ γ'.v (p + n) (p + n + m) ⋯ ≫ (M.shiftFunctorObjXIso a (p + n + m) q ⋯).hom

Tactic:
assoc

Goal state after:
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
K L M : CochainComplex C ℤ
n : ℤ
γ : Cochain K L n
m a : ℤ
γ' : Cochain L ((CategoryTheory.shiftFunctor (CochainComplex C ℤ) a).obj M) m
nm : ℤ
hnm : n + m = nm
nm' : ℤ
hnm' : nm + a = nm'
m' : ℤ
hm' : m + a = m'
p q : ℤ
hpq : p + nm' = q
⊢ γ.v p (p + n) ⋯ ≫ γ'.v (p + n) (p + n + m) ⋯ ≫ (M.shiftFunctorObjXIso a (p + n + m) q ⋯).hom =
    γ.v p (p + n) ⋯ ≫ γ'.v (p + n) (p + n + m) ⋯ ≫ (M.shiftFunctorObjXIso a (p + n + m) q ⋯).hom
Module: Mathlib.Algebra.Homology.HomotopyCategory.HomComplexShift

Goal state before:
pp: case e_a.e_a
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
K L M : CochainComplex C ℤ
n : ℤ
γ : Cochain K L n
a n' : ℤ
hn' : n + a = n'
m t t' : ℤ
γ' : Cochain L M m
h : n + m = t
ht' : t + a = t'
p q : ℤ
hpq : p + t' = q
h' : n' + m = t'
⊢ (a * (n' + m)).negOnePow = (a * m).negOnePow * (a * n').negOnePow

Tactic:
add_comm n',

Goal state after:
case e_a.e_a
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
K L M : CochainComplex C ℤ
n : ℤ
γ : Cochain K L n
a n' : ℤ
hn' : n + a = n'
m t t' : ℤ
γ' : Cochain L M m
h : n + m = t
ht' : t + a = t'
p q : ℤ
hpq : p + t' = q
h' : n' + m = t'
⊢ (a * (m + n')).negOnePow = (a * m).negOnePow * (a * n').negOnePow
Module: Mathlib.Algebra.Homology.HomotopyCategory.HomComplexShift

Goal state before:
pp: case neg
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
K L : CochainComplex C ℤ
n : ℤ
γ : Cochain K L n
a n' m' : ℤ
hn' : n' + a = n
m : ℤ
hm' : m' + a = m
hnm : ¬n + 1 = m
hnm' : ¬n' + 1 = m'
⊢ δ n' m' (γ.rightShift a n' hn') = a.negOnePow • (δ n m γ).rightShift a m' hm'

Tactic:
rw [δ_shape _ _ hnm', δ_shape _ _ hnm, rightShift_zero, smul_zero]

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

Goal state before:
pp: C : Type u
inst✝⁶ : Category.{v, u} C
inst✝⁵ : HasShift C ℤ
J : Type u_1
T : J → Triangle C
inst✝⁴ : HasProduct fun j ↦ (T j).obj₁
inst✝³ : HasProduct fun j ↦ (T j).obj₂
inst✝² : HasProduct fun j ↦ (T j).obj₃
inst✝¹ : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₁
inst✝ : HasZeroMorphisms C
h : ∀ (j : J), (T j).mor₃ ≫ (shiftFunctor C 1).map (T j).mor₁ = 0
this : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₂
⊢ ((Limits.Pi.map fun j ↦ (T j).mor₃) ≫
      (inv (piComparison (shiftFunctor C 1) fun j ↦ (T j).obj₁) ≫
          (shiftFunctor C 1).map (Pi.lift fun j ↦ Pi.π (fun j ↦ (T j).obj₁) j ≫ (T j).mor₁)) ≫
        piComparison (shiftFunctor C 1) fun j ↦ (T j).obj₂) =
    0

Tactic:
assoc

Goal state after:
C : Type u
inst✝⁶ : Category.{v, u} C
inst✝⁵ : HasShift C ℤ
J : Type u_1
T : J → Triangle C
inst✝⁴ : HasProduct fun j ↦ (T j).obj₁
inst✝³ : HasProduct fun j ↦ (T j).obj₂
inst✝² : HasProduct fun j ↦ (T j).obj₃
inst✝¹ : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₁
inst✝ : HasZeroMorphisms C
h : ∀ (j : J), (T j).mor₃ ≫ (shiftFunctor C 1).map (T j).mor₁ = 0
this : HasProduct fun j ↦ (shiftFunctor C 1).obj (T j).obj₂
⊢ ((Limits.Pi.map fun j ↦ (T j).mor₃) ≫
      inv (piComparison (shiftFunctor C 1) fun j ↦ (T j).obj₁) ≫
        (shiftFunctor C 1).map (Pi.lift fun j ↦ Pi.π (fun j ↦ (T j).obj₁) j ≫ (T j).mor₁) ≫
          piComparison (shiftFunctor C 1) fun j ↦ (T j).obj₂) =
    0
Module: Mathlib.Algebra.Homology.HomotopyCategory.HomComplexShift

Goal state before:
pp: case pos.e_a.e_a
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
K L : CochainComplex C ℤ
n : ℤ
γ : Cochain K L n
a n' m' : ℤ
hn' : n + a = n'
m : ℤ
hm' : m + a = m'
hnm : n + 1 = m
hnm' : n' + 1 = m'
p q : ℤ
hpq : p + m' = q
⊢ (a * n' + a * (a - 1) / 2).negOnePow = a.negOnePow * (a * (n' + 1) + a * (a - 1) / 2).negOnePow

Tactic:
add_comm n',

Goal state after:
case pos.e_a.e_a
C : Type u
inst✝¹ : Category.{v, u} C
inst✝ : Preadditive C
K L : CochainComplex C ℤ
n : ℤ
γ : Cochain K L n
a n' m' : ℤ
hn' : n + a = n'
m : ℤ
hm' : m + a = m'
hnm : n + 1 = m
hnm' : n' + 1 = m'
p q : ℤ
hpq : p + m' = q
⊢ (a * n' + a * (a - 1) / 2).negOnePow = a.negOnePow * (a * (1 + n') + a * (a - 1) / 2).negOnePow
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), (CategoryTheory.shiftFunctor C n).Additive
hC : Pretriangulated C
T : Triangle C
hT : T ∈ distinguishedTriangles
h₁ : IsZero T.obj₁
h₂ : IsZero T.obj₂
⊢ IsZero ((CategoryTheory.shiftFunctor C 1).obj T.obj₁)

Tactic:
simp only [IsZero.iff_id_eq_zero] at h₁ ⊢

Goal state after:
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), (CategoryTheory.shiftFunctor C n).Additive
hC : Pretriangulated C
T : Triangle C
hT : T ∈ distinguishedTriangles
h₂ : IsZero T.obj₂
h₁ : 𝟙 T.obj₁ = 0
⊢ 𝟙 ((CategoryTheory.shiftFunctor C 1).obj T.obj₁) = 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
T T' : Triangle C
φ : T ⟶ T'
hT : T ∈ distinguishedTriangles
hT' : T' ∈ distinguishedTriangles
h₁ : IsIso φ.hom₁
h₃ : IsIso φ.hom₃
A : C
g : A ⟶ T.obj₁
hf : (g ≫ T.mor₁) ≫ φ.hom₂ = 0
⊢ g ≫ T.mor₁ = 0

Tactic:
assoc

Goal state after:
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
T T' : Triangle C
φ : T ⟶ T'
hT : T ∈ distinguishedTriangles
hT' : T' ∈ distinguishedTriangles
h₁ : IsIso φ.hom₁
h₃ : IsIso φ.hom₃
A : C
g : A ⟶ T.obj₁
hf : g ≫ T.mor₁ ≫ φ.hom₂ = 0
⊢ g ≫ T.mor₁ = 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
T : Triangle C
hT : T ∈ distinguishedTriangles
hT₀ : T.mor₃ = 0
inr : T.obj₃ ⟶ T.obj₂
inr_snd : inr ≫ T.mor₂ = 𝟙 T.obj₃
fst : T.obj₂ ⟶ T.obj₁
total : fst ≫ T.mor₁ + T.mor₂ ≫ inr = 𝟙 T.obj₂
⊢ BinaryBiproductData T.obj₁ T.obj₃

Tactic:
by
  have : Mono T.mor₁ := T.mono₁ hT hT₀
  have eq : fst ≫ T.mor₁ = 𝟙 T.obj₂ - T.mor₂ ≫ inr := by rw [← total, add_sub_cancel_right]
  exact
    { bicone :=
      { pt := T.obj₂
        fst := fst
        snd := T.mor₂
        inl := T.mor₁
        inr := inr
        inl_fst := by
          simp only [← cancel_mono T.mor₁, assoc, id_comp, eq, comp_sub, comp_id,
            comp_distTriang_mor_zero₁₂_assoc _ hT, zero_comp, sub_zero]
        inl_snd := comp_distTriang_mor_zero₁₂ _ hT
        inr_fst := by
          simp only [← cancel_mono T.mor₁, assoc, eq, comp_sub, reassoc_of% inr_snd,
            comp_id, sub_self, zero_comp]
        inr_snd := inr_snd }
      isBilimit := isBinaryBilimitOfTotal _ total }

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

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 : HasBinaryBiproducts C
inst✝¹ : Preadditive D
inst✝ : HasBinaryBiproducts D
K L : CochainComplex C ℤ
φ : K ⟶ L
K₁ L₁ K₂ L₂ K₃ L₃ : CochainComplex C ℤ
φ₁ : K₁ ⟶ L₁
φ₂ : K₂ ⟶ L₂
a : K₁ ⟶ K₂
b : L₁ ⟶ L₂
H : Homotopy (φ₁ ≫ b) (a ≫ φ₂)
⊢ (HomotopyCategory.quotient C (ComplexShape.up ℤ)).map (triangle φ₁).mor₃ ≫
      (Functor.commShiftIso (HomotopyCategory.quotient C (ComplexShape.up ℤ)) 1).hom.app K₁ ≫
        (CategoryTheory.shiftFunctor (HomotopyCategory C (ComplexShape.up ℤ)) 1).map
          ((HomotopyCategory.quotient C (ComplexShape.up ℤ)).map a) =
    ((HomotopyCategory.quotient C (ComplexShape.up ℤ)).map (triangle φ₁).mor₃ ≫
        (HomotopyCategory.quotient C (ComplexShape.up ℤ)).map
          ((CategoryTheory.shiftFunctor (CochainComplex C ℤ) 1).map a)) ≫
      (Functor.commShiftIso (HomotopyCategory.quotient C (ComplexShape.up ℤ)) 1).hom.app K₂

Tactic:
assoc

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 : HasBinaryBiproducts C
inst✝¹ : Preadditive D
inst✝ : HasBinaryBiproducts D
K L : CochainComplex C ℤ
φ : K ⟶ L
K₁ L₁ K₂ L₂ K₃ L₃ : CochainComplex C ℤ
φ₁ : K₁ ⟶ L₁
φ₂ : K₂ ⟶ L₂
a : K₁ ⟶ K₂
b : L₁ ⟶ L₂
H : Homotopy (φ₁ ≫ b) (a ≫ φ₂)
⊢ (HomotopyCategory.quotient C (ComplexShape.up ℤ)).map (triangle φ₁).mor₃ ≫
      (Functor.commShiftIso (HomotopyCategory.quotient C (ComplexShape.up ℤ)) 1).hom.app K₁ ≫
        (CategoryTheory.shiftFunctor (HomotopyCategory C (ComplexShape.up ℤ)) 1).map
          ((HomotopyCategory.quotient C (ComplexShape.up ℤ)).map a) =
    (HomotopyCategory.quotient C (ComplexShape.up ℤ)).map (triangle φ₁).mor₃ ≫
      (HomotopyCategory.quotient C (ComplexShape.up ℤ)).map
          ((CategoryTheory.shiftFunctor (CochainComplex C ℤ) 1).map a) ≫
        (Functor.commShiftIso (HomotopyCategory.quotient C (ComplexShape.up ℤ)) 1).hom.app K₂
Module: Mathlib.Algebra.Homology.HomotopyCategory.Pretriangulated

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 : HasBinaryBiproducts C
inst✝¹ : Preadditive D
inst✝ : HasBinaryBiproducts D
K L : CochainComplex C ℤ
φ : K ⟶ L
K₁ L₁ K₂ L₂ K₃ L₃ : CochainComplex C ℤ
φ₁ : K₁ ⟶ L₁
φ₂ : K₂ ⟶ L₂
φ₃ : K₃ ⟶ L₃
a : K₁ ⟶ K₂
b : L₁ ⟶ L₂
comm : φ₁ ≫ b = a ≫ φ₂
a' : K₂ ⟶ K₃
b' : L₂ ⟶ L₃
comm' : φ₂ ≫ b' = a' ≫ φ₃
⊢ a ≫ a' ≫ φ₃ = (a ≫ a') ≫ φ₃

Tactic:
assoc

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 : HasBinaryBiproducts C
inst✝¹ : Preadditive D
inst✝ : HasBinaryBiproducts D
K L : CochainComplex C ℤ
φ : K ⟶ L
K₁ L₁ K₂ L₂ K₃ L₃ : CochainComplex C ℤ
φ₁ : K₁ ⟶ L₁
φ₂ : K₂ ⟶ L₂
φ₃ : K₃ ⟶ L₃
a : K₁ ⟶ K₂
b : L₁ ⟶ L₂
comm : φ₁ ≫ b = a ≫ φ₂
a' : K₂ ⟶ K₃
b' : L₂ ⟶ L₃
comm' : φ₂ ≫ b' = a' ≫ φ₃
⊢ a ≫ a' ≫ φ₃ = a ≫ a' ≫ φ₃
Module: Mathlib.Algebra.Homology.HomotopyCategory.DegreewiseSplit

Goal state before:
pp: C : Type u_1
inst✝¹ : Category.{v, u_1} C
inst✝ : Preadditive C
S : ShortComplex (CochainComplex C ℤ)
σ : (n : ℤ) → (S.map (eval C (ComplexShape.up ℤ) n)).Splitting
p : ℤ
this : Mono (S.f.f (p + 2))
r_f : ∀ (n : ℤ), (σ n).r ≫ S.f.f n = 𝟙 (S.X₂.X n) - S.g.f n ≫ (σ n).s
s_g : ∀ (n : ℤ), (σ n).s ≫ S.g.f n = 𝟙 (S.X₃.X n)
⊢ ((σ p).s ≫ S.X₂.d p (p + 1) ≫ (σ (p + 1)).r) ≫ S.X₁.d (p + 1) (p + 2) +
      Int.negOnePow 2 • S.X₃.d p (p + 1) ≫ (σ (p + 1)).s ≫ S.X₂.d (p + 1) (p + 2) ≫ (σ (p + 2)).r =
    0

Tactic:
show Int.negOnePow 2 = 1 by rfl,

Goal state after:
C : Type u_1
inst✝¹ : Category.{v, u_1} C
inst✝ : Preadditive C
S : ShortComplex (CochainComplex C ℤ)
σ : (n : ℤ) → (S.map (eval C (ComplexShape.up ℤ) n)).Splitting
p : ℤ
this : Mono (S.f.f (p + 2))
r_f : ∀ (n : ℤ), (σ n).r ≫ S.f.f n = 𝟙 (S.X₂.X n) - S.g.f n ≫ (σ n).s
s_g : ∀ (n : ℤ), (σ n).s ≫ S.g.f n = 𝟙 (S.X₃.X n)
⊢ ((σ p).s ≫ S.X₂.d p (p + 1) ≫ (σ (p + 1)).r) ≫ S.X₁.d (p + 1) (p + 2) +
      1 • S.X₃.d p (p + 1) ≫ (σ (p + 1)).s ≫ S.X₂.d (p + 1) (p + 2) ≫ (σ (p + 2)).r =
    0
Module: Mathlib.Algebra.Homology.HomologySequence

Goal state before:
pp: C : Type u_1
ι : Type u_2
inst✝² : Category.{v_1, u_1} C
inst✝¹ : Preadditive C
c : ComplexShape ι
K : HomologicalComplex C c
i j : ι
hij : c.Rel i j
inst✝ : CategoryWithHomology C
S : ShortComplex C :=
  { X₁ := K.homology i, X₂ := K.opcycles i, X₃ := K.cycles j, f := K.homologyι i, g := K.opcyclesToCycles i j,
    zero := ⋯ }
S' : ShortComplex C :=
  { X₁ := K.homology i, X₂ := K.opcycles i, X₃ := K.X j, f := K.homologyι i, g := K.fromOpcycles i j, zero := ⋯ }
⊢ (composableArrows₃ K i j).Exact

Tactic:
let ι : S ⟶ S' :=
    { τ₁ := 𝟙 _
      τ₂ := 𝟙 _
      τ₃ := K.iCycles j }

Goal state after:
C : Type u_1
ι✝ : Type u_2
inst✝² : Category.{v_1, u_1} C
inst✝¹ : Preadditive C
c : ComplexShape ι✝
K : HomologicalComplex C c
i j : ι✝
hij : c.Rel i j
inst✝ : CategoryWithHomology C
S : ShortComplex C :=
  { X₁ := K.homology i, X₂ := K.opcycles i, X₃ := K.cycles j, f := K.homologyι i, g := K.opcyclesToCycles i j,
    zero := ⋯ }
S' : ShortComplex C :=
  { X₁ := K.homology i, X₂ := K.opcycles i, X₃ := K.X j, f := K.homologyι i, g := K.fromOpcycles i j, zero := ⋯ }
ι : S ⟶ S' := { τ₁ := 𝟙 S.X₁, τ₂ := 𝟙 S.X₂, τ₃ := K.iCycles j, comm₁₂ := ⋯, comm₂₃ := ⋯ }
⊢ (composableArrows₃ K i j).Exact
Module: Mathlib.Algebra.Homology.HomologySequence

Goal state before:
pp: C : Type u_1
ι : Type u_2
inst✝⁵ : Category.{v_1, u_1} C
inst✝⁴ : Abelian C
c : ComplexShape ι
S : ShortComplex (HomologicalComplex C c)
hS : S.Exact
inst✝³ : Epi S.g
i : ι
inst✝² : S.X₁.HasHomology i
inst✝¹ : S.X₂.HasHomology i
inst✝ : S.X₃.HasHomology i
⊢ { X₁ := S.X₁.opcycles i, X₂ := S.X₂.opcycles i, X₃ := S.X₃.opcycles i, f := opcyclesMap S.f i, g := opcyclesMap S.g i,
      zero := ⋯ }.Exact

Tactic:
have : Epi (ShortComplex.map S (eval C c i)).g := by dsimp; infer_instance

Goal state after:
C : Type u_1
ι : Type u_2
inst✝⁵ : Category.{v_1, u_1} C
inst✝⁴ : Abelian C
c : ComplexShape ι
S : ShortComplex (HomologicalComplex C c)
hS : S.Exact
inst✝³ : Epi S.g
i : ι
inst✝² : S.X₁.HasHomology i
inst✝¹ : S.X₂.HasHomology i
inst✝ : S.X₃.HasHomology i
this : Epi (S.map (eval C c i)).g
⊢ { X₁ := S.X₁.opcycles i, X₂ := S.X₂.opcycles i, X₃ := S.X₃.opcycles i, f := opcyclesMap S.f i, g := opcyclesMap S.g i,
      zero := ⋯ }.Exact
Module: Mathlib.CategoryTheory.Triangulated.Triangulated

Goal state before:
pp: case refine_1
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
inst✝ : IsTriangulated C
X₁ X₂ X₃ Z₁₂ Z₂₃ Z₁₃ : C
u₁₂ : X₁ ⟶ X₂
u₂₃ : X₂ ⟶ X₃
u₁₃ : X₁ ⟶ X₃
comm : u₁₂ ≫ u₂₃ = u₁₃
v₁₂ : Z₁₂ ⟶ X₁
w₁₂ : X₂ ⟶ (shiftFunctor C 1).obj Z₁₂
h₁₂ : Triangle.mk v₁₂ u₁₂ w₁₂ ∈ distinguishedTriangles
v₂₃ : Z₂₃ ⟶ X₂
w₂₃ : X₃ ⟶ (shiftFunctor C 1).obj Z₂₃
h₂₃ : Triangle.mk v₂₃ u₂₃ w₂₃ ∈ distinguishedTriangles
v₁₃ : Z₁₃ ⟶ X₁
w₁₃ : X₃ ⟶ (shiftFunctor C 1).obj Z₁₃
h₁₃ : Triangle.mk v₁₃ u₁₃ w₁₃ ∈ distinguishedTriangles
o : Octahedron comm ⋯ ⋯ ⋯ := someOctahedron comm ⋯ ⋯ ⋯
m₁ : Z₁₂ ⟶ Z₁₃ := (shiftShiftNeg Z₁₂ 1).inv ≫ (shiftFunctor C (-1)).map o.m₁ ≫ (shiftShiftNeg Z₁₃ 1).hom
m₃ : Z₁₃ ⟶ Z₂₃ := (shiftShiftNeg Z₁₃ 1).inv ≫ (shiftFunctor C (-1)).map o.m₃ ≫ (shiftShiftNeg Z₂₃ 1).hom
eq₁ : w₁₂ ≫ o.m₁ = u₂₃ ≫ w₁₃
eq₂ : o.m₁ ≫ (shiftFunctor C 1).map v₁₃ = (shiftFunctor C 1).map v₁₂
eq₃ : w₁₃ ≫ o.m₃ = w₂₃
eq₄ : (shiftFunctor C 1).map v₁₃ ≫ (shiftFunctor C 1).map u₁₂ = o.m₃ ≫ (shiftFunctor C 1).map v₂₃
⊢ (shiftFunctorCompIsoId C 1 (-1) ⋯).inv.app Z₁₂ ≫
      (shiftFunctor C (-1)).map o.m₁ ≫
        (shiftFunctor C (-1)).map ((shiftFunctor C 1).map v₁₃) ≫ (shiftFunctorCompIsoId C 1 (-1) ⋯).hom.app X₁ =
    v₁₂

Tactic:
nth_rw 2 [← assoc]

Goal state after:
case refine_1
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
inst✝ : IsTriangulated C
X₁ X₂ X₃ Z₁₂ Z₂₃ Z₁₃ : C
u₁₂ : X₁ ⟶ X₂
u₂₃ : X₂ ⟶ X₃
u₁₃ : X₁ ⟶ X₃
comm : u₁₂ ≫ u₂₃ = u₁₃
v₁₂ : Z₁₂ ⟶ X₁
w₁₂ : X₂ ⟶ (shiftFunctor C 1).obj Z₁₂
h₁₂ : Triangle.mk v₁₂ u₁₂ w₁₂ ∈ distinguishedTriangles
v₂₃ : Z₂₃ ⟶ X₂
w₂₃ : X₃ ⟶ (shiftFunctor C 1).obj Z₂₃
h₂₃ : Triangle.mk v₂₃ u₂₃ w₂₃ ∈ distinguishedTriangles
v₁₃ : Z₁₃ ⟶ X₁
w₁₃ : X₃ ⟶ (shiftFunctor C 1).obj Z₁₃
h₁₃ : Triangle.mk v₁₃ u₁₃ w₁₃ ∈ distinguishedTriangles
o : Octahedron comm ⋯ ⋯ ⋯ := someOctahedron comm ⋯ ⋯ ⋯
m₁ : Z₁₂ ⟶ Z₁₃ := (shiftShiftNeg Z₁₂ 1).inv ≫ (shiftFunctor C (-1)).map o.m₁ ≫ (shiftShiftNeg Z₁₃ 1).hom
m₃ : Z₁₃ ⟶ Z₂₃ := (shiftShiftNeg Z₁₃ 1).inv ≫ (shiftFunctor C (-1)).map o.m₃ ≫ (shiftShiftNeg Z₂₃ 1).hom
eq₁ : w₁₂ ≫ o.m₁ = u₂₃ ≫ w₁₃
eq₂ : o.m₁ ≫ (shiftFunctor C 1).map v₁₃ = (shiftFunctor C 1).map v₁₂
eq₃ : w₁₃ ≫ o.m₃ = w₂₃
eq₄ : (shiftFunctor C 1).map v₁₃ ≫ (shiftFunctor C 1).map u₁₂ = o.m₃ ≫ (shiftFunctor C 1).map v₂₃
⊢ (shiftFunctorCompIsoId C 1 (-1) ⋯).inv.app Z₁₂ ≫
      ((shiftFunctor C (-1)).map o.m₁ ≫ (shiftFunctor C (-1)).map ((shiftFunctor C 1).map v₁₃)) ≫
        (shiftFunctorCompIsoId C 1 (-1) ⋯).hom.app X₁ =
    v₁₂
Module: Mathlib.CategoryTheory.Triangulated.Triangulated

Goal state before:
pp: case refine_4
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
inst✝ : IsTriangulated C
X₁ X₂ X₃ Z₁₂ Z₂₃ Z₁₃ : C
u₁₂ : X₁ ⟶ X₂
u₂₃ : X₂ ⟶ X₃
u₁₃ : X₁ ⟶ X₃
comm : u₁₂ ≫ u₂₃ = u₁₃
v₁₂ : Z₁₂ ⟶ X₁
w₁₂ : X₂ ⟶ (shiftFunctor C 1).obj Z₁₂
h₁₂ : Triangle.mk v₁₂ u₁₂ w₁₂ ∈ distinguishedTriangles
v₂₃ : Z₂₃ ⟶ X₂
w₂₃ : X₃ ⟶ (shiftFunctor C 1).obj Z₂₃
h₂₃ : Triangle.mk v₂₃ u₂₃ w₂₃ ∈ distinguishedTriangles
v₁₃ : Z₁₃ ⟶ X₁
w₁₃ : X₃ ⟶ (shiftFunctor C 1).obj Z₁₃
h₁₃ : Triangle.mk v₁₃ u₁₃ w₁₃ ∈ distinguishedTriangles
o : Octahedron comm ⋯ ⋯ ⋯ := someOctahedron comm ⋯ ⋯ ⋯
m₁ : Z₁₂ ⟶ Z₁₃ := (shiftShiftNeg Z₁₂ 1).inv ≫ (shiftFunctor C (-1)).map o.m₁ ≫ (shiftShiftNeg Z₁₃ 1).hom
m₃ : Z₁₃ ⟶ Z₂₃ := (shiftShiftNeg Z₁₃ 1).inv ≫ (shiftFunctor C (-1)).map o.m₃ ≫ (shiftShiftNeg Z₂₃ 1).hom
eq₁ : w₁₂ ≫ o.m₁ = u₂₃ ≫ w₁₃
eq₂ : o.m₁ ≫ (shiftFunctor C 1).map v₁₃ = (shiftFunctor C 1).map v₁₂
eq₃ : w₁₃ ≫ o.m₃ = w₂₃
eq₄ : (shiftFunctor C 1).map v₁₃ ≫ (shiftFunctor C 1).map u₁₂ = o.m₃ ≫ (shiftFunctor C 1).map v₂₃
⊢ (shiftFunctorCompIsoId C 1 (-1) ⋯).inv.app Z₁₃ ≫
      (shiftFunctor C (-1)).map o.m₃ ≫
        (shiftFunctor C (-1)).map ((shiftFunctor C 1).map v₂₃) ≫ (shiftFunctorCompIsoId C 1 (-1) ⋯).hom.app X₂ =
    v₁₃ ≫ u₁₂

Tactic:
nth_rw 2 [← assoc]

Goal state after:
case refine_4
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
inst✝ : IsTriangulated C
X₁ X₂ X₃ Z₁₂ Z₂₃ Z₁₃ : C
u₁₂ : X₁ ⟶ X₂
u₂₃ : X₂ ⟶ X₃
u₁₃ : X₁ ⟶ X₃
comm : u₁₂ ≫ u₂₃ = u₁₃
v₁₂ : Z₁₂ ⟶ X₁
w₁₂ : X₂ ⟶ (shiftFunctor C 1).obj Z₁₂
h₁₂ : Triangle.mk v₁₂ u₁₂ w₁₂ ∈ distinguishedTriangles
v₂₃ : Z₂₃ ⟶ X₂
w₂₃ : X₃ ⟶ (shiftFunctor C 1).obj Z₂₃
h₂₃ : Triangle.mk v₂₃ u₂₃ w₂₃ ∈ distinguishedTriangles
v₁₃ : Z₁₃ ⟶ X₁
w₁₃ : X₃ ⟶ (shiftFunctor C 1).obj Z₁₃
h₁₃ : Triangle.mk v₁₃ u₁₃ w₁₃ ∈ distinguishedTriangles
o : Octahedron comm ⋯ ⋯ ⋯ := someOctahedron comm ⋯ ⋯ ⋯
m₁ : Z₁₂ ⟶ Z₁₃ := (shiftShiftNeg Z₁₂ 1).inv ≫ (shiftFunctor C (-1)).map o.m₁ ≫ (shiftShiftNeg Z₁₃ 1).hom
m₃ : Z₁₃ ⟶ Z₂₃ := (shiftShiftNeg Z₁₃ 1).inv ≫ (shiftFunctor C (-1)).map o.m₃ ≫ (shiftShiftNeg Z₂₃ 1).hom
eq₁ : w₁₂ ≫ o.m₁ = u₂₃ ≫ w₁₃
eq₂ : o.m₁ ≫ (shiftFunctor C 1).map v₁₃ = (shiftFunctor C 1).map v₁₂
eq₃ : w₁₃ ≫ o.m₃ = w₂₃
eq₄ : (shiftFunctor C 1).map v₁₃ ≫ (shiftFunctor C 1).map u₁₂ = o.m₃ ≫ (shiftFunctor C 1).map v₂₃
⊢ (shiftFunctorCompIsoId C 1 (-1) ⋯).inv.app Z₁₃ ≫
      ((shiftFunctor C (-1)).map o.m₃ ≫ (shiftFunctor C (-1)).map ((shiftFunctor C 1).map v₂₃)) ≫
        (shiftFunctorCompIsoId C 1 (-1) ⋯).hom.app X₂ =
    v₁₃ ≫ u₁₂
Module: Mathlib.CategoryTheory.Localization.Construction

Goal state before:
pp: C : Type uC
inst✝¹ : Category.{uC', uC} C
W : MorphismProperty C
D : Type uD
inst✝ : Category.{uD', uD} D
G : C ⥤ D
hG : W.IsInvertedBy G
X Y : C
f : X ⟶ Y
⊢ (W.Q ⋙ lift G hG).map f = eqToHom ⋯ ≫ G.map f ≫ eqToHom ⋯

Tactic:
simp only [Functor.comp_map, eqToHom_refl, comp_id, id_comp]

Goal state after:
C : Type uC
inst✝¹ : Category.{uC', uC} C
W : MorphismProperty C
D : Type uD
inst✝ : Category.{uD', uD} D
G : C ⥤ D
hG : W.IsInvertedBy G
X Y : C
f : X ⟶ Y
⊢ (lift G hG).map (W.Q.map f) = G.map f
Module: Mathlib.CategoryTheory.Localization.Predicate

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝³ : Category.{v_1, u_1} C
inst✝² : Category.{v_2, u_2} D
L : C ⥤ D
W : MorphismProperty C
E : Type u_3
inst✝¹ : Category.{v_3, u_3} E
inst✝ : L.IsLocalization W
X✝ Y✝ : D ⥤ E
τ : X✝ ⟶ Y✝
x✝ : C
⊢ τ.app (L.obj (W.Q.obj x✝).as.obj) ≫ eqToHom ⋯ = eqToHom ⋯ ≫ ((whiskeringLeftFunctor L W E).map τ).hom.app x✝

Tactic:
eqToHom_refl,

Goal state after:
C : Type u_1
D : Type u_2
inst✝³ : Category.{v_1, u_1} C
inst✝² : Category.{v_2, u_2} D
L : C ⥤ D
W : MorphismProperty C
E : Type u_3
inst✝¹ : Category.{v_3, u_3} E
inst✝ : L.IsLocalization W
X✝ Y✝ : D ⥤ E
τ : X✝ ⟶ Y✝
x✝ : C
⊢ τ.app (L.obj (W.Q.obj x✝).as.obj) ≫
      𝟙 (((Construction.WhiskeringLeftEquivalence.functor W E).obj (Construction.lift L ⋯ ⋙ Y✝)).obj.obj x✝) =
    eqToHom ⋯ ≫ ((whiskeringLeftFunctor L W E).map τ).hom.app x✝