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vandermonde (v : Fin n → R) : Matrix (Fin n) (Fin n) R := .of fun i j ↦ (v i) ^ j.1
def
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
vandermonde
`vandermonde v` is the square matrix with `i`th row equal to `1, v i, v i ^ 2, v i ^ 3, ...`.
vandermonde_eq_projVandermonde (v : Fin n → R) : vandermonde v = projVandermonde v 1 := by simp [projVandermonde, rectVandermonde, vandermonde]
lemma
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
vandermonde_eq_projVandermonde
null
projVandermonde_apply {v w : Fin n → R} {i j : Fin n} : projVandermonde v w i j = (v i) ^ j.1 * (w i) ^ j.rev.1 := rfl
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
projVandermonde_apply
We don't mark this as `@[simp]` because the RHS is not simp-nf, and simplifying the RHS gives a bothersome `Nat` subtraction.
rectVandermonde_apply {α : Type*} {v w : α → R} {i : α} {j : Fin n} : rectVandermonde v w n i j = (v i) ^ j.1 * (w i) ^ j.rev.1 := rfl @[simp]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
rectVandermonde_apply
null
vandermonde_apply (v : Fin n → R) (i j) : vandermonde v i j = v i ^ (j : ℕ) := rfl @[simp]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
vandermonde_apply
null
vandermonde_cons (v0 : R) (v : Fin n → R) : vandermonde (Fin.cons v0 v : Fin n.succ → R) = Fin.cons (fun (j : Fin n.succ) => v0 ^ (j : ℕ)) fun i => Fin.cons 1 fun j => v i * vandermonde v i j := by ext i j refine Fin.cases (by simp) (fun i => ?_) i refine Fin.cases (by simp) (fun j => ?_) j simp...
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
vandermonde_cons
null
vandermonde_succ (v : Fin n.succ → R) : vandermonde v = .of Fin.cons (fun (j : Fin n.succ) => v 0 ^ (j : ℕ)) fun i => Fin.cons 1 fun j => v i.succ * vandermonde (Fin.tail v) i j := by conv_lhs => rw [← Fin.cons_self_tail v, vandermonde_cons] rfl
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
vandermonde_succ
null
vandermonde_mul_vandermonde_transpose (v w : Fin n → R) (i j) : (vandermonde v * (vandermonde w)ᵀ) i j = ∑ k : Fin n, (v i * w j) ^ (k : ℕ) := by simp only [vandermonde_apply, Matrix.mul_apply, Matrix.transpose_apply, mul_pow]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
vandermonde_mul_vandermonde_transpose
null
vandermonde_transpose_mul_vandermonde (v : Fin n → R) (i j) : ((vandermonde v)ᵀ * vandermonde v) i j = ∑ k : Fin n, v k ^ (i + j : ℕ) := by simp only [vandermonde_apply, Matrix.mul_apply, Matrix.transpose_apply, pow_add]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
vandermonde_transpose_mul_vandermonde
null
rectVandermonde_apply_zero_right {α : Type*} {v w : α → R} {i : α} (hw : w i = 0) : rectVandermonde v w (n + 1) i = Pi.single (Fin.last n) ((v i) ^ n) := by ext j obtain rfl | hlt := j.le_last.eq_or_lt · simp [rectVandermonde_apply] rw [rectVandermonde_apply, Pi.single_eq_of_ne hlt.ne, hw, zero_pow, mul_zer...
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
rectVandermonde_apply_zero_right
null
projVandermonde_apply_of_ne_zero {v w : Fin (n + 1) → K} {i j : Fin (n + 1)} (hw : w i ≠ 0) : projVandermonde v w i j = (v i) ^ j.1 * (w i) ^ n / (w i) ^ j.1 := by rw [projVandermonde_apply, eq_div_iff (by simp [hw]), mul_assoc, ← pow_add, rev_add_cast]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
projVandermonde_apply_of_ne_zero
null
projVandermonde_apply_zero_right {v w : Fin (n + 1) → R} {i : Fin (n + 1)} (hw : w i = 0) : projVandermonde v w i = Pi.single (Fin.last n) ((v i) ^ n) := by ext j obtain rfl | hlt := j.le_last.eq_or_lt · simp [projVandermonde_apply] rw [projVandermonde_apply, Pi.single_eq_of_ne hlt.ne, hw, zero_pow, mul_ze...
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
projVandermonde_apply_zero_right
null
projVandermonde_comp {v w : Fin n → R} (f : Fin n → Fin n) : projVandermonde (v ∘ f) (w ∘ f) = (projVandermonde v w).submatrix f id := rfl
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
projVandermonde_comp
null
projVandermonde_map {R' : Type*} [CommRing R'] (φ : R →+* R') (v w : Fin n → R) : projVandermonde (fun i ↦ φ (v i)) (fun i ↦ φ (w i)) = φ.mapMatrix (projVandermonde v w) := by ext i j simp [projVandermonde_apply]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
projVandermonde_map
null
private det_projVandermonde_of_field (v w : Fin n → K) : (projVandermonde v w).det = ∏ i : Fin n, ∏ j ∈ Finset.Ioi i, (v j * w i - v i * w j) := by induction n with | zero => simp | succ n ih => /- We can assume not all `w i` are zero, and therefore that `w 0 ≠ 0`, since otherwise we can swap row `0` with...
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
det_projVandermonde_of_field
null
det_projVandermonde (v w : Fin n → R) : (projVandermonde v w).det = ∏ i : Fin n, ∏ j ∈ Finset.Ioi i, (v j * w i - v i * w j) := by let u (b : Bool) (i : Fin n) := (algebraMap (MvPolynomial (Fin n × Bool) ℤ) (FractionRing (MvPolynomial (Fin n × Bool) ℤ))) (MvPolynomial.X ⟨i, b⟩) have hdet := det_projVandermo...
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
det_projVandermonde
The formula for the determinant of a projective Vandermonde matrix.
det_vandermonde (v : Fin n → R) : det (vandermonde v) = ∏ i : Fin n, ∏ j ∈ Ioi i, (v j - v i) := by simp [vandermonde_eq_projVandermonde, det_projVandermonde]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
det_vandermonde
The formula for the determinant of a Vandermonde matrix.
det_vandermonde_eq_zero_iff [IsDomain R] {v : Fin n → R} : det (vandermonde v) = 0 ↔ ∃ i j : Fin n, v i = v j ∧ i ≠ j := by constructor · simp only [det_vandermonde v, Finset.prod_eq_zero_iff, sub_eq_zero, forall_exists_index] rintro i ⟨_, j, h₁, h₂⟩ exact ⟨j, i, h₂, (mem_Ioi.mp h₁).ne'⟩ · simp only [...
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
det_vandermonde_eq_zero_iff
null
det_vandermonde_ne_zero_iff [IsDomain R] {v : Fin n → R} : det (vandermonde v) ≠ 0 ↔ Function.Injective v := by unfold Function.Injective simp only [det_vandermonde_eq_zero_iff, Ne, not_exists, not_and, Classical.not_not] @[simp]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
det_vandermonde_ne_zero_iff
null
det_vandermonde_add (v : Fin n → R) (a : R) : (Matrix.vandermonde fun i ↦ v i + a).det = (Matrix.vandermonde v).det := by simp [Matrix.det_vandermonde] @[simp]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
det_vandermonde_add
null
det_vandermonde_sub (v : Fin n → R) (a : R) : (Matrix.vandermonde fun i ↦ v i - a).det = (Matrix.vandermonde v).det := by rw [← det_vandermonde_add v (- a)] simp only [← sub_eq_add_neg]
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
det_vandermonde_sub
null
eq_zero_of_forall_index_sum_pow_mul_eq_zero [IsDomain R] {f v : Fin n → R} (hf : Function.Injective f) (hfv : ∀ j, (∑ i : Fin n, f j ^ (i : ℕ) * v i) = 0) : v = 0 := eq_zero_of_mulVec_eq_zero (det_vandermonde_ne_zero_iff.mpr hf) (funext hfv)
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
eq_zero_of_forall_index_sum_pow_mul_eq_zero
null
eq_zero_of_forall_index_sum_mul_pow_eq_zero [IsDomain R] {f v : Fin n → R} (hf : Function.Injective f) (hfv : ∀ j, (∑ i, v i * f j ^ (i : ℕ)) = 0) : v = 0 := by apply eq_zero_of_forall_index_sum_pow_mul_eq_zero hf simp_rw [mul_comm] exact hfv
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
eq_zero_of_forall_index_sum_mul_pow_eq_zero
null
eq_zero_of_forall_pow_sum_mul_pow_eq_zero [IsDomain R] {f v : Fin n → R} (hf : Function.Injective f) (hfv : ∀ i : Fin n, (∑ j : Fin n, v j * f j ^ (i : ℕ)) = 0) : v = 0 := eq_zero_of_vecMul_eq_zero (det_vandermonde_ne_zero_iff.mpr hf) (funext hfv) open Polynomial
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
eq_zero_of_forall_pow_sum_mul_pow_eq_zero
null
eval_matrixOfPolynomials_eq_vandermonde_mul_matrixOfPolynomials (v : Fin n → R) (p : Fin n → R[X]) (h_deg : ∀ i, (p i).natDegree ≤ i) : Matrix.of (fun i j => ((p j).eval (v i))) = (Matrix.vandermonde v) * (Matrix.of (fun (i j : Fin n) => (p j).coeff i)) := by ext i j simp_rw [Matrix.mul_apply, eval, Mat...
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
eval_matrixOfPolynomials_eq_vandermonde_mul_matrixOfPolynomials
null
det_eval_matrixOfPolynomials_eq_det_vandermonde (v : Fin n → R) (p : Fin n → R[X]) (h_deg : ∀ i, (p i).natDegree = i) (h_monic : ∀ i, Monic <| p i) : (Matrix.vandermonde v).det = (Matrix.of (fun i j => ((p j).eval (v i)))).det := by rw [Matrix.eval_matrixOfPolynomials_eq_vandermonde_mul_matrixOfPolynomials v ...
theorem
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
det_eval_matrixOfPolynomials_eq_det_vandermonde
null
det_vandermonde_id_eq_superFactorial (n : ℕ) : (vandermonde fun i : Fin (n + 1) ↦ (i : R)).det = n.superFactorial := by induction n with | zero => simp | succ n hn => rw [Nat.superFactorial, det_vandermonde, Fin.prod_univ_succAbove _ 0] push_cast congr · simp only [Fin.val_zero, Nat.cast_zero,...
lemma
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
det_vandermonde_id_eq_superFactorial
null
private of_eval_descPochhammer_eq_mul_of_choose {n : ℕ} (v : Fin n → ℕ) : (of fun i j : Fin n => (descPochhammer ℤ j).eval (v i : ℤ)).det = (∏ i : Fin n, Nat.factorial i) * (of fun i j : Fin n => (Nat.choose (v i) j : ℤ)).det := by convert det_mul_row (fun (i : Fin n) => ((Nat.factorial (i : ℕ)) : ℤ)) _...
lemma
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
of_eval_descPochhammer_eq_mul_of_choose
null
superFactorial_dvd_vandermonde_det {n : ℕ} (v : Fin (n + 1) → ℤ) : ↑n.superFactorial ∣ (vandermonde v).det := by let m := inf' univ ⟨0, mem_univ _⟩ v let w' := fun i ↦ (v i - m).toNat have hw' : ∀ i, (w' i : ℤ) = v i - m := fun i ↦ Int.toNat_sub_of_le (inf'_le _ (mem_univ _)) have h := det_eval_matrixOfPoly...
lemma
LinearAlgebra
[ "Mathlib.Data.Nat.Factorial.SuperFactorial", "Mathlib.LinearAlgebra.Matrix.Block", "Mathlib.LinearAlgebra.Matrix.Nondegenerate", "Mathlib.RingTheory.Localization.FractionRing", "Mathlib.RingTheory.Polynomial.Pochhammer" ]
Mathlib/LinearAlgebra/Vandermonde.lean
superFactorial_dvd_vandermonde_det
null
hidden {α : Sort*} {a : α} := a variable {α : Sort*}
abbrev
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
hidden
An identity function with its main argument implicit. This will be printed as `hidden` even if it is applied to a large term, so it can be used for elision, as done in the `elide` and `unelide` tactics.
congr_heq {α β γ : Sort _} {f : α → γ} {g : β → γ} {x : α} {y : β} (h₁ : f ≍ g) (h₂ : x ≍ y) : f x = g y := by cases h₂; cases h₁; rfl
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
congr_heq
null
congr_arg_heq {β : α → Sort*} (f : ∀ a, β a) : ∀ {a₁ a₂ : α}, a₁ = a₂ → f a₁ ≍ f a₂ | _, _, rfl => HEq.rfl
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
congr_arg_heq
null
dcongr_heq.{u, v} {α₁ α₂ : Sort u} {β₁ : α₁ → Sort v} {β₂ : α₂ → Sort v} {f₁ : ∀ a, β₁ a} {f₂ : ∀ a, β₂ a} {a₁ : α₁} {a₂ : α₂} (hargs : a₁ ≍ a₂) (ht : ∀ t₁ t₂, t₁ ≍ t₂ → β₁ t₁ = β₂ t₂) (hf : α₁ = α₂ → β₁ ≍ β₂ → f₁ ≍ f₂) : f₁ a₁ ≍ f₂ a₂ := by cases hargs cases funext fun v => ht v v ....
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
dcongr_heq.
null
ne_and_eq_iff_right {a b c : α} (h : b ≠ c) : a ≠ b ∧ a = c ↔ a = c := and_iff_right_of_imp (fun h2 => h2.symm ▸ h.symm)
lemma
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
ne_and_eq_iff_right
null
Fact (p : Prop) : Prop where /-- `Fact.out` contains the unwrapped witness for the fact represented by the instance of `Fact p`. -/ out : p library_note "fact non-instances"/-- In most cases, we should not have global instances of `Fact`; typeclass search is not an advanced proof search engine, and adding any suc...
class
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Fact
Wrapper for adding elementary propositions to the type class systems. Warning: this can easily be abused. See the rest of this docstring for details. Certain propositions should not be treated as a class globally, but sometimes it is very convenient to be able to use the type class system in specific circumstances. F...
Fact.elim {p : Prop} (h : Fact p) : p := h.1
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Fact.elim
null
fact_iff {p : Prop} : Fact p ↔ p := ⟨fun h ↦ h.1, fun h ↦ ⟨h⟩⟩
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
fact_iff
null
Function.swap₂ {ι₁ ι₂ : Sort*} {κ₁ : ι₁ → Sort*} {κ₂ : ι₂ → Sort*} {φ : ∀ i₁, κ₁ i₁ → ∀ i₂, κ₂ i₂ → Sort*} (f : ∀ i₁ j₁ i₂ j₂, φ i₁ j₁ i₂ j₂) (i₂ j₂ i₁ j₁) : φ i₁ j₁ i₂ j₂ := f i₁ j₁ i₂ j₂
abbrev
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Function.swap₂
Swaps two pairs of arguments to a function.
imp_iff_right_iff {a b : Prop} : (a → b ↔ b) ↔ a ∨ b := open scoped Classical in Decidable.imp_iff_right_iff
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
imp_iff_right_iff
null
and_or_imp {a b c : Prop} : a ∧ b ∨ (a → c) ↔ a → b ∨ c := open scoped Classical in Decidable.and_or_imp
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
and_or_imp
null
protected Function.mt {a b : Prop} : (a → b) → ¬b → ¬a := mt /-! ### Declarations about `not` -/ alias dec_em := Decidable.em
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Function.mt
Provide modus tollens (`mt`) as dot notation for implications.
dec_em' (p : Prop) [Decidable p] : ¬p ∨ p := (dec_em p).symm alias em := Classical.em
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
dec_em'
null
em' (p : Prop) : ¬p ∨ p := (em p).symm
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
em'
null
or_not {p : Prop} : p ∨ ¬p := em _
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
or_not
null
Decidable.eq_or_ne {α : Sort*} (x y : α) [Decidable (x = y)] : x = y ∨ x ≠ y := dec_em <| x = y
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Decidable.eq_or_ne
null
Decidable.ne_or_eq {α : Sort*} (x y : α) [Decidable (x = y)] : x ≠ y ∨ x = y := dec_em' <| x = y
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Decidable.ne_or_eq
null
eq_or_ne {α : Sort*} (x y : α) : x = y ∨ x ≠ y := em <| x = y
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
eq_or_ne
null
ne_or_eq {α : Sort*} (x y : α) : x ≠ y ∨ x = y := em' <| x = y
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
ne_or_eq
null
by_contradiction {p : Prop} : (¬p → False) → p := open scoped Classical in Decidable.byContradiction
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
by_contradiction
null
by_cases {p q : Prop} (hpq : p → q) (hnpq : ¬p → q) : q := open scoped Classical in if hp : p then hpq hp else hnpq hp alias by_contra := by_contradiction library_note "decidable namespace"/-- In most of mathlib, we use the law of excluded middle (LEM) and the axiom of choice (AC) freely. The `Decidable` namespace co...
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
by_cases
null
of_not_not {a : Prop} : ¬¬a → a := by_contra
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
of_not_not
null
not_ne_iff {α : Sort*} {a b : α} : ¬a ≠ b ↔ a = b := not_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_ne_iff
null
of_not_imp : ¬(a → b) → a := open scoped Classical in Decidable.of_not_imp alias Not.decidable_imp_symm := Decidable.not_imp_symm
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
of_not_imp
null
Not.imp_symm : (¬a → b) → ¬b → a := open scoped Classical in Not.decidable_imp_symm
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Not.imp_symm
null
not_imp_comm : ¬a → b ↔ ¬b → a := open scoped Classical in Decidable.not_imp_comm @[simp] theorem not_imp_self : ¬a → a ↔ a := open scoped Classical in Decidable.not_imp_self
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_imp_comm
null
Imp.swap {a b : Sort*} {c : Prop} : a → b → c ↔ b → a → c := ⟨fun h x y ↦ h y x, fun h x y ↦ h y x⟩ alias Iff.not := not_congr
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Imp.swap
null
Iff.not_left (h : a ↔ ¬b) : ¬a ↔ b := h.not.trans not_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Iff.not_left
null
Iff.not_right (h : ¬a ↔ b) : a ↔ ¬b := not_not.symm.trans h.not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Iff.not_right
null
protected Iff.ne {α β : Sort*} {a b : α} {c d : β} : (a = b ↔ c = d) → (a ≠ b ↔ c ≠ d) := Iff.not
lemma
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Iff.ne
null
Iff.ne_left {α β : Sort*} {a b : α} {c d : β} : (a = b ↔ c ≠ d) → (a ≠ b ↔ c = d) := Iff.not_left
lemma
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Iff.ne_left
null
Iff.ne_right {α β : Sort*} {a b : α} {c d : β} : (a ≠ b ↔ c = d) → (a = b ↔ c ≠ d) := Iff.not_right /-! ### Declarations about `Xor'` -/
lemma
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Iff.ne_right
null
Xor' (a b : Prop) := (a ∧ ¬b) ∨ (b ∧ ¬a) @[grind =] theorem xor_def {a b : Prop} : Xor' a b ↔ (a ∧ ¬b) ∨ (b ∧ ¬a) := Iff.rfl
def
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Xor'
2025-07-31. Upstream `Xor` has been renamed to `XorOp`. 2025-09-16. The deprecation for `Xor` has been removed. Anytime after v4.25.0-rc1 lands we rename this back to `Xor`. -/ /-- `Xor' a b` is the exclusive-or of propositions.
@[simp] xor_true : Xor' True = Not := by grind @[simp] theorem xor_false : Xor' False = id := by grind
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
xor_true
null
xor_comm (a b : Prop) : Xor' a b = Xor' b a := by grind
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
xor_comm
null
@[simp] xor_self (a : Prop) : Xor' a a = False := by grind @[simp] theorem xor_not_left : Xor' (¬a) b ↔ (a ↔ b) := by grind @[simp] theorem xor_not_right : Xor' a (¬b) ↔ (a ↔ b) := by grind
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
xor_self
null
xor_not_not : Xor' (¬a) (¬b) ↔ Xor' a b := by grind
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
xor_not_not
null
protected Xor'.or (h : Xor' a b) : a ∨ b := by grind /-! ### Declarations about `and` -/ alias Iff.and := and_congr alias ⟨And.rotate, _⟩ := and_rotate
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Xor'.or
null
and_symm_right {α : Sort*} (a b : α) (p : Prop) : p ∧ a = b ↔ p ∧ b = a := by simp [eq_comm]
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
and_symm_right
null
and_symm_left {α : Sort*} (a b : α) (p : Prop) : a = b ∧ p ↔ b = a ∧ p := by simp [eq_comm] /-! ### Declarations about `or` -/ alias Iff.or := or_congr alias ⟨Or.rotate, _⟩ := or_rotate
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
and_symm_left
null
Or.elim3 {c d : Prop} (h : a ∨ b ∨ c) (ha : a → d) (hb : b → d) (hc : c → d) : d := Or.elim h ha fun h₂ ↦ Or.elim h₂ hb hc
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Or.elim3
null
Or.imp3 {d e c f : Prop} (had : a → d) (hbe : b → e) (hcf : c → f) : a ∨ b ∨ c → d ∨ e ∨ f := Or.imp had <| Or.imp hbe hcf export Classical (or_iff_not_imp_left or_iff_not_imp_right)
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Or.imp3
null
not_or_of_imp : (a → b) → ¬a ∨ b := open scoped Classical in Decidable.not_or_of_imp
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_or_of_imp
null
protected Decidable.or_not_of_imp [Decidable a] (h : a → b) : b ∨ ¬a := dite _ (Or.inl ∘ h) Or.inr
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Decidable.or_not_of_imp
null
or_not_of_imp : (a → b) → b ∨ ¬a := open scoped Classical in Decidable.or_not_of_imp
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
or_not_of_imp
null
imp_iff_not_or : a → b ↔ ¬a ∨ b := open scoped Classical in Decidable.imp_iff_not_or
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
imp_iff_not_or
null
imp_iff_or_not {b a : Prop} : b → a ↔ a ∨ ¬b := open scoped Classical in Decidable.imp_iff_or_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
imp_iff_or_not
null
not_imp_not : ¬a → ¬b ↔ b → a := open scoped Classical in Decidable.not_imp_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_imp_not
null
imp_and_neg_imp_iff (p q : Prop) : (p → q) ∧ (¬p → q) ↔ q := by simp
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
imp_and_neg_imp_iff
null
protected Function.mtr : (¬a → ¬b) → b → a := not_imp_not.mp
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
Function.mtr
Provide the reverse of modus tollens (`mt`) as dot notation for implications.
or_congr_left' {c a b : Prop} (h : ¬c → (a ↔ b)) : a ∨ c ↔ b ∨ c := open scoped Classical in Decidable.or_congr_left' h
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
or_congr_left'
null
or_congr_right' {c : Prop} (h : ¬a → (b ↔ c)) : a ∨ b ↔ a ∨ c := open scoped Classical in Decidable.or_congr_right' h /-! ### Declarations about distributivity -/ /-! Declarations about `iff` -/ alias Iff.iff := iff_congr
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
or_congr_right'
null
iff_mpr_iff_true_intro {P : Prop} (h : P) : Iff.mpr (iff_true_intro h) True.intro = h := rfl
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
iff_mpr_iff_true_intro
null
imp_or {a b c : Prop} : a → b ∨ c ↔ (a → b) ∨ (a → c) := open scoped Classical in Decidable.imp_or
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
imp_or
null
imp_or' {a : Sort*} {b c : Prop} : a → b ∨ c ↔ (a → b) ∨ (a → c) := open scoped Classical in Decidable.imp_or'
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
imp_or'
null
not_imp : ¬(a → b) ↔ a ∧ ¬b := open scoped Classical in Decidable.not_imp_iff_and_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_imp
null
peirce (a b : Prop) : ((a → b) → a) → a := open scoped Classical in Decidable.peirce _ _
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
peirce
null
not_iff_not : (¬a ↔ ¬b) ↔ (a ↔ b) := open scoped Classical in Decidable.not_iff_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_iff_not
null
not_iff_comm : (¬a ↔ b) ↔ (¬b ↔ a) := open scoped Classical in Decidable.not_iff_comm
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_iff_comm
null
not_iff : ¬(a ↔ b) ↔ (¬a ↔ b) := open scoped Classical in Decidable.not_iff
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_iff
null
iff_not_comm : (a ↔ ¬b) ↔ (b ↔ ¬a) := open scoped Classical in Decidable.iff_not_comm
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
iff_not_comm
null
iff_iff_and_or_not_and_not : (a ↔ b) ↔ a ∧ b ∨ ¬a ∧ ¬b := open scoped Classical in Decidable.iff_iff_and_or_not_and_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
iff_iff_and_or_not_and_not
null
iff_iff_not_or_and_or_not : (a ↔ b) ↔ (¬a ∨ b) ∧ (a ∨ ¬b) := open scoped Classical in Decidable.iff_iff_not_or_and_or_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
iff_iff_not_or_and_or_not
null
not_and_not_right : ¬(a ∧ ¬b) ↔ a → b := open scoped Classical in Decidable.not_and_not_right /-! ### De Morgan's laws -/
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_and_not_right
null
not_and_or : ¬(a ∧ b) ↔ ¬a ∨ ¬b := open scoped Classical in Decidable.not_and_iff_not_or_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
not_and_or
One of **de Morgan's laws**: the negation of a conjunction is logically equivalent to the disjunction of the negations.
or_iff_not_and_not : a ∨ b ↔ ¬(¬a ∧ ¬b) := open scoped Classical in Decidable.or_iff_not_not_and_not
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
or_iff_not_and_not
null
and_iff_not_or_not : a ∧ b ↔ ¬(¬a ∨ ¬b) := open scoped Classical in Decidable.and_iff_not_not_or_not @[simp] theorem not_xor (P Q : Prop) : ¬Xor' P Q ↔ (P ↔ Q) := by simp only [not_and, Xor', not_or, not_not, ← iff_iff_implies_and_implies]
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
and_iff_not_or_not
null
xor_iff_not_iff (P Q : Prop) : Xor' P Q ↔ ¬(P ↔ Q) := (not_xor P Q).not_right
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
xor_iff_not_iff
null
xor_iff_iff_not : Xor' a b ↔ (a ↔ ¬b) := by simp only [← @xor_not_right a, not_not]
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
xor_iff_iff_not
null
xor_iff_not_iff' : Xor' a b ↔ (¬a ↔ b) := by simp only [← @xor_not_left _ b, not_not]
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
xor_iff_not_iff'
null
xor_iff_or_and_not_and (a b : Prop) : Xor' a b ↔ (a ∨ b) ∧ (¬(a ∧ b)) := by rw [Xor', or_and_right, not_and_or, and_or_left, and_not_self_iff, false_or, and_or_left, and_not_self_iff, or_false]
theorem
Logic
[ "Mathlib.Tactic.Attr.Register", "Mathlib.Tactic.AdaptationNote", "Mathlib.Tactic.Basic", "Batteries.Logic", "Batteries.Tactic.Trans", "Batteries.Util.LibraryNote", "Mathlib.Data.Nat.Notation", "Mathlib.Data.Int.Notation" ]
Mathlib/Logic/Basic.lean
xor_iff_or_and_not_and
null