Context
stringlengths
57
6.04k
file_name
stringlengths
21
79
start
int64
14
1.49k
end
int64
18
1.5k
theorem
stringlengths
25
1.55k
proof
stringlengths
5
7.36k
rank
int64
0
2.4k
import Mathlib.MeasureTheory.Constructions.Prod.Basic import Mathlib.MeasureTheory.Group.Measure #align_import measure_theory.group.prod from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" noncomputable section open Set hiding prod_eq open Function MeasureTheory open Filter hiding map open scoped Classical ENNReal Pointwise MeasureTheory variable (G : Type*) [MeasurableSpace G] variable [Group G] [MeasurableMul₂ G] variable (μ ν : Measure G) [SigmaFinite ν] [SigmaFinite μ] {s : Set G} @[to_additive "The map `(x, y) ↦ (x, x + y)` as a `MeasurableEquiv`."] protected def MeasurableEquiv.shearMulRight [MeasurableInv G] : G × G ≃ᵐ G × G := { Equiv.prodShear (Equiv.refl _) Equiv.mulLeft with measurable_toFun := measurable_fst.prod_mk measurable_mul measurable_invFun := measurable_fst.prod_mk <| measurable_fst.inv.mul measurable_snd } #align measurable_equiv.shear_mul_right MeasurableEquiv.shearMulRight #align measurable_equiv.shear_add_right MeasurableEquiv.shearAddRight @[to_additive "The map `(x, y) ↦ (x, y - x)` as a `MeasurableEquiv` with as inverse `(x, y) ↦ (x, y + x)`."] protected def MeasurableEquiv.shearDivRight [MeasurableInv G] : G × G ≃ᵐ G × G := { Equiv.prodShear (Equiv.refl _) Equiv.divRight with measurable_toFun := measurable_fst.prod_mk <| measurable_snd.div measurable_fst measurable_invFun := measurable_fst.prod_mk <| measurable_snd.mul measurable_fst } #align measurable_equiv.shear_div_right MeasurableEquiv.shearDivRight #align measurable_equiv.shear_sub_right MeasurableEquiv.shearSubRight variable {G} namespace MeasureTheory open Measure section LeftInvariant @[to_additive measurePreserving_prod_add " The shear mapping `(x, y) ↦ (x, x + y)` preserves the measure `μ × ν`. "] theorem measurePreserving_prod_mul [IsMulLeftInvariant ν] : MeasurePreserving (fun z : G × G => (z.1, z.1 * z.2)) (μ.prod ν) (μ.prod ν) := (MeasurePreserving.id μ).skew_product measurable_mul <| Filter.eventually_of_forall <| map_mul_left_eq_self ν #align measure_theory.measure_preserving_prod_mul MeasureTheory.measurePreserving_prod_mul #align measure_theory.measure_preserving_prod_add MeasureTheory.measurePreserving_prod_add @[to_additive measurePreserving_prod_add_swap " The map `(x, y) ↦ (y, y + x)` sends the measure `μ × ν` to `ν × μ`. "] theorem measurePreserving_prod_mul_swap [IsMulLeftInvariant μ] : MeasurePreserving (fun z : G × G => (z.2, z.2 * z.1)) (μ.prod ν) (ν.prod μ) := (measurePreserving_prod_mul ν μ).comp measurePreserving_swap #align measure_theory.measure_preserving_prod_mul_swap MeasureTheory.measurePreserving_prod_mul_swap #align measure_theory.measure_preserving_prod_add_swap MeasureTheory.measurePreserving_prod_add_swap @[to_additive] theorem measurable_measure_mul_right (hs : MeasurableSet s) : Measurable fun x => μ ((fun y => y * x) ⁻¹' s) := by suffices Measurable fun y => μ ((fun x => (x, y)) ⁻¹' ((fun z : G × G => ((1 : G), z.1 * z.2)) ⁻¹' univ ×ˢ s)) by convert this using 1; ext1 x; congr 1 with y : 1; simp apply measurable_measure_prod_mk_right apply measurable_const.prod_mk measurable_mul (MeasurableSet.univ.prod hs) infer_instance #align measure_theory.measurable_measure_mul_right MeasureTheory.measurable_measure_mul_right #align measure_theory.measurable_measure_add_right MeasureTheory.measurable_measure_add_right variable [MeasurableInv G] @[to_additive measurePreserving_prod_neg_add "The map `(x, y) ↦ (x, - x + y)` is measure-preserving."] theorem measurePreserving_prod_inv_mul [IsMulLeftInvariant ν] : MeasurePreserving (fun z : G × G => (z.1, z.1⁻¹ * z.2)) (μ.prod ν) (μ.prod ν) := (measurePreserving_prod_mul μ ν).symm <| MeasurableEquiv.shearMulRight G #align measure_theory.measure_preserving_prod_inv_mul MeasureTheory.measurePreserving_prod_inv_mul #align measure_theory.measure_preserving_prod_neg_add MeasureTheory.measurePreserving_prod_neg_add variable [IsMulLeftInvariant μ] @[to_additive measurePreserving_prod_neg_add_swap "The map `(x, y) ↦ (y, - y + x)` sends `μ × ν` to `ν × μ`."] theorem measurePreserving_prod_inv_mul_swap : MeasurePreserving (fun z : G × G => (z.2, z.2⁻¹ * z.1)) (μ.prod ν) (ν.prod μ) := (measurePreserving_prod_inv_mul ν μ).comp measurePreserving_swap #align measure_theory.measure_preserving_prod_inv_mul_swap MeasureTheory.measurePreserving_prod_inv_mul_swap #align measure_theory.measure_preserving_prod_neg_add_swap MeasureTheory.measurePreserving_prod_neg_add_swap @[to_additive measurePreserving_add_prod_neg "The map `(x, y) ↦ (y + x, - x)` is measure-preserving."] theorem measurePreserving_mul_prod_inv [IsMulLeftInvariant ν] : MeasurePreserving (fun z : G × G => (z.2 * z.1, z.1⁻¹)) (μ.prod ν) (μ.prod ν) := by convert (measurePreserving_prod_inv_mul_swap ν μ).comp (measurePreserving_prod_mul_swap μ ν) using 1 ext1 ⟨x, y⟩ simp_rw [Function.comp_apply, mul_inv_rev, inv_mul_cancel_right] #align measure_theory.measure_preserving_mul_prod_inv MeasureTheory.measurePreserving_mul_prod_inv #align measure_theory.measure_preserving_add_prod_neg MeasureTheory.measurePreserving_add_prod_neg @[to_additive]
Mathlib/MeasureTheory/Group/Prod.lean
161
172
theorem quasiMeasurePreserving_inv : QuasiMeasurePreserving (Inv.inv : G → G) μ μ := by
refine ⟨measurable_inv, AbsolutelyContinuous.mk fun s hsm hμs => ?_⟩ rw [map_apply measurable_inv hsm, inv_preimage] have hf : Measurable fun z : G × G => (z.2 * z.1, z.1⁻¹) := (measurable_snd.mul measurable_fst).prod_mk measurable_fst.inv suffices map (fun z : G × G => (z.2 * z.1, z.1⁻¹)) (μ.prod μ) (s⁻¹ ×ˢ s⁻¹) = 0 by simpa only [(measurePreserving_mul_prod_inv μ μ).map_eq, prod_prod, mul_eq_zero (M₀ := ℝ≥0∞), or_self_iff] using this have hsm' : MeasurableSet (s⁻¹ ×ˢ s⁻¹) := hsm.inv.prod hsm.inv simp_rw [map_apply hf hsm', prod_apply_symm (μ := μ) (ν := μ) (hf hsm'), preimage_preimage, mk_preimage_prod, inv_preimage, inv_inv, measure_mono_null inter_subset_right hμs, lintegral_zero]
411
import Mathlib.MeasureTheory.Constructions.Prod.Basic import Mathlib.MeasureTheory.Group.Measure #align_import measure_theory.group.prod from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" noncomputable section open Set hiding prod_eq open Function MeasureTheory open Filter hiding map open scoped Classical ENNReal Pointwise MeasureTheory variable (G : Type*) [MeasurableSpace G] variable [Group G] [MeasurableMul₂ G] variable (μ ν : Measure G) [SigmaFinite ν] [SigmaFinite μ] {s : Set G} @[to_additive "The map `(x, y) ↦ (x, x + y)` as a `MeasurableEquiv`."] protected def MeasurableEquiv.shearMulRight [MeasurableInv G] : G × G ≃ᵐ G × G := { Equiv.prodShear (Equiv.refl _) Equiv.mulLeft with measurable_toFun := measurable_fst.prod_mk measurable_mul measurable_invFun := measurable_fst.prod_mk <| measurable_fst.inv.mul measurable_snd } #align measurable_equiv.shear_mul_right MeasurableEquiv.shearMulRight #align measurable_equiv.shear_add_right MeasurableEquiv.shearAddRight @[to_additive "The map `(x, y) ↦ (x, y - x)` as a `MeasurableEquiv` with as inverse `(x, y) ↦ (x, y + x)`."] protected def MeasurableEquiv.shearDivRight [MeasurableInv G] : G × G ≃ᵐ G × G := { Equiv.prodShear (Equiv.refl _) Equiv.divRight with measurable_toFun := measurable_fst.prod_mk <| measurable_snd.div measurable_fst measurable_invFun := measurable_fst.prod_mk <| measurable_snd.mul measurable_fst } #align measurable_equiv.shear_div_right MeasurableEquiv.shearDivRight #align measurable_equiv.shear_sub_right MeasurableEquiv.shearSubRight variable {G} namespace MeasureTheory open Measure section RightInvariant @[to_additive measurePreserving_prod_add_right] theorem measurePreserving_prod_mul_right [IsMulRightInvariant ν] : MeasurePreserving (fun z : G × G => (z.1, z.2 * z.1)) (μ.prod ν) (μ.prod ν) := MeasurePreserving.skew_product (g := fun x y => y * x) (MeasurePreserving.id μ) (measurable_snd.mul measurable_fst) <| Filter.eventually_of_forall <| map_mul_right_eq_self ν #align measure_theory.measure_preserving_prod_mul_right MeasureTheory.measurePreserving_prod_mul_right #align measure_theory.measure_preserving_prod_add_right MeasureTheory.measurePreserving_prod_add_right @[to_additive measurePreserving_prod_add_swap_right " The map `(x, y) ↦ (y, x + y)` sends the measure `μ × ν` to `ν × μ`. "] theorem measurePreserving_prod_mul_swap_right [IsMulRightInvariant μ] : MeasurePreserving (fun z : G × G => (z.2, z.1 * z.2)) (μ.prod ν) (ν.prod μ) := (measurePreserving_prod_mul_right ν μ).comp measurePreserving_swap #align measure_theory.measure_preserving_prod_mul_swap_right MeasureTheory.measurePreserving_prod_mul_swap_right #align measure_theory.measure_preserving_prod_add_swap_right MeasureTheory.measurePreserving_prod_add_swap_right @[to_additive measurePreserving_add_prod " The map `(x, y) ↦ (x + y, y)` preserves the measure `μ × ν`. "] theorem measurePreserving_mul_prod [IsMulRightInvariant μ] : MeasurePreserving (fun z : G × G => (z.1 * z.2, z.2)) (μ.prod ν) (μ.prod ν) := measurePreserving_swap.comp <| by apply measurePreserving_prod_mul_swap_right μ ν #align measure_theory.measure_preserving_mul_prod MeasureTheory.measurePreserving_mul_prod #align measure_theory.measure_preserving_add_prod MeasureTheory.measurePreserving_add_prod variable [MeasurableInv G] @[to_additive measurePreserving_prod_sub "The map `(x, y) ↦ (x, y - x)` is measure-preserving."] theorem measurePreserving_prod_div [IsMulRightInvariant ν] : MeasurePreserving (fun z : G × G => (z.1, z.2 / z.1)) (μ.prod ν) (μ.prod ν) := (measurePreserving_prod_mul_right μ ν).symm (MeasurableEquiv.shearDivRight G).symm #align measure_theory.measure_preserving_prod_div MeasureTheory.measurePreserving_prod_div #align measure_theory.measure_preserving_prod_sub MeasureTheory.measurePreserving_prod_sub @[to_additive measurePreserving_prod_sub_swap "The map `(x, y) ↦ (y, x - y)` sends `μ × ν` to `ν × μ`."] theorem measurePreserving_prod_div_swap [IsMulRightInvariant μ] : MeasurePreserving (fun z : G × G => (z.2, z.1 / z.2)) (μ.prod ν) (ν.prod μ) := (measurePreserving_prod_div ν μ).comp measurePreserving_swap #align measure_theory.measure_preserving_prod_div_swap MeasureTheory.measurePreserving_prod_div_swap #align measure_theory.measure_preserving_prod_sub_swap MeasureTheory.measurePreserving_prod_sub_swap @[to_additive measurePreserving_sub_prod " The map `(x, y) ↦ (x - y, y)` preserves the measure `μ × ν`. "] theorem measurePreserving_div_prod [IsMulRightInvariant μ] : MeasurePreserving (fun z : G × G => (z.1 / z.2, z.2)) (μ.prod ν) (μ.prod ν) := measurePreserving_swap.comp <| by apply measurePreserving_prod_div_swap μ ν #align measure_theory.measure_preserving_div_prod MeasureTheory.measurePreserving_div_prod #align measure_theory.measure_preserving_sub_prod MeasureTheory.measurePreserving_sub_prod @[to_additive measurePreserving_add_prod_neg_right "The map `(x, y) ↦ (x + y, - x)` is measure-preserving."]
Mathlib/MeasureTheory/Group/Prod.lean
424
429
theorem measurePreserving_mul_prod_inv_right [IsMulRightInvariant μ] [IsMulRightInvariant ν] : MeasurePreserving (fun z : G × G => (z.1 * z.2, z.1⁻¹)) (μ.prod ν) (μ.prod ν) := by
convert (measurePreserving_prod_div_swap ν μ).comp (measurePreserving_prod_mul_swap_right μ ν) using 1 ext1 ⟨x, y⟩ simp_rw [Function.comp_apply, div_mul_eq_div_div_swap, div_self', one_div]
411
import Mathlib.MeasureTheory.Measure.Content import Mathlib.MeasureTheory.Group.Prod import Mathlib.Topology.Algebra.Group.Compact #align_import measure_theory.measure.haar.basic from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" noncomputable section open Set Inv Function TopologicalSpace MeasurableSpace open scoped NNReal Classical ENNReal Pointwise Topology namespace MeasureTheory namespace Measure section Group variable {G : Type*} [Group G] namespace haar -- Porting note: Even in `noncomputable section`, a definition with `to_additive` require -- `noncomputable` to generate an additive definition. -- Please refer to leanprover/lean4#2077. @[to_additive addIndex "additive version of `MeasureTheory.Measure.haar.index`"] noncomputable def index (K V : Set G) : ℕ := sInf <| Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } #align measure_theory.measure.haar.index MeasureTheory.Measure.haar.index #align measure_theory.measure.haar.add_index MeasureTheory.Measure.haar.addIndex @[to_additive addIndex_empty]
Mathlib/MeasureTheory/Measure/Haar/Basic.lean
102
104
theorem index_empty {V : Set G} : index ∅ V = 0 := by
simp only [index, Nat.sInf_eq_zero]; left; use ∅ simp only [Finset.card_empty, empty_subset, mem_setOf_eq, eq_self_iff_true, and_self_iff]
412
import Mathlib.MeasureTheory.Measure.Content import Mathlib.MeasureTheory.Group.Prod import Mathlib.Topology.Algebra.Group.Compact #align_import measure_theory.measure.haar.basic from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" noncomputable section open Set Inv Function TopologicalSpace MeasurableSpace open scoped NNReal Classical ENNReal Pointwise Topology namespace MeasureTheory namespace Measure section Group variable {G : Type*} [Group G] namespace haar -- Porting note: Even in `noncomputable section`, a definition with `to_additive` require -- `noncomputable` to generate an additive definition. -- Please refer to leanprover/lean4#2077. @[to_additive addIndex "additive version of `MeasureTheory.Measure.haar.index`"] noncomputable def index (K V : Set G) : ℕ := sInf <| Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } #align measure_theory.measure.haar.index MeasureTheory.Measure.haar.index #align measure_theory.measure.haar.add_index MeasureTheory.Measure.haar.addIndex @[to_additive addIndex_empty] theorem index_empty {V : Set G} : index ∅ V = 0 := by simp only [index, Nat.sInf_eq_zero]; left; use ∅ simp only [Finset.card_empty, empty_subset, mem_setOf_eq, eq_self_iff_true, and_self_iff] #align measure_theory.measure.haar.index_empty MeasureTheory.Measure.haar.index_empty #align measure_theory.measure.haar.add_index_empty MeasureTheory.Measure.haar.addIndex_empty variable [TopologicalSpace G] @[to_additive "additive version of `MeasureTheory.Measure.haar.prehaar`"] noncomputable def prehaar (K₀ U : Set G) (K : Compacts G) : ℝ := (index (K : Set G) U : ℝ) / index K₀ U #align measure_theory.measure.haar.prehaar MeasureTheory.Measure.haar.prehaar #align measure_theory.measure.haar.add_prehaar MeasureTheory.Measure.haar.addPrehaar @[to_additive]
Mathlib/MeasureTheory/Measure/Haar/Basic.lean
122
123
theorem prehaar_empty (K₀ : PositiveCompacts G) {U : Set G} : prehaar (K₀ : Set G) U ⊥ = 0 := by
rw [prehaar, Compacts.coe_bot, index_empty, Nat.cast_zero, zero_div]
412
import Mathlib.MeasureTheory.Measure.Content import Mathlib.MeasureTheory.Group.Prod import Mathlib.Topology.Algebra.Group.Compact #align_import measure_theory.measure.haar.basic from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" noncomputable section open Set Inv Function TopologicalSpace MeasurableSpace open scoped NNReal Classical ENNReal Pointwise Topology namespace MeasureTheory namespace Measure section Group variable {G : Type*} [Group G] namespace haar -- Porting note: Even in `noncomputable section`, a definition with `to_additive` require -- `noncomputable` to generate an additive definition. -- Please refer to leanprover/lean4#2077. @[to_additive addIndex "additive version of `MeasureTheory.Measure.haar.index`"] noncomputable def index (K V : Set G) : ℕ := sInf <| Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } #align measure_theory.measure.haar.index MeasureTheory.Measure.haar.index #align measure_theory.measure.haar.add_index MeasureTheory.Measure.haar.addIndex @[to_additive addIndex_empty] theorem index_empty {V : Set G} : index ∅ V = 0 := by simp only [index, Nat.sInf_eq_zero]; left; use ∅ simp only [Finset.card_empty, empty_subset, mem_setOf_eq, eq_self_iff_true, and_self_iff] #align measure_theory.measure.haar.index_empty MeasureTheory.Measure.haar.index_empty #align measure_theory.measure.haar.add_index_empty MeasureTheory.Measure.haar.addIndex_empty variable [TopologicalSpace G] @[to_additive "additive version of `MeasureTheory.Measure.haar.prehaar`"] noncomputable def prehaar (K₀ U : Set G) (K : Compacts G) : ℝ := (index (K : Set G) U : ℝ) / index K₀ U #align measure_theory.measure.haar.prehaar MeasureTheory.Measure.haar.prehaar #align measure_theory.measure.haar.add_prehaar MeasureTheory.Measure.haar.addPrehaar @[to_additive] theorem prehaar_empty (K₀ : PositiveCompacts G) {U : Set G} : prehaar (K₀ : Set G) U ⊥ = 0 := by rw [prehaar, Compacts.coe_bot, index_empty, Nat.cast_zero, zero_div] #align measure_theory.measure.haar.prehaar_empty MeasureTheory.Measure.haar.prehaar_empty #align measure_theory.measure.haar.add_prehaar_empty MeasureTheory.Measure.haar.addPrehaar_empty @[to_additive]
Mathlib/MeasureTheory/Measure/Haar/Basic.lean
128
129
theorem prehaar_nonneg (K₀ : PositiveCompacts G) {U : Set G} (K : Compacts G) : 0 ≤ prehaar (K₀ : Set G) U K := by
apply div_nonneg <;> norm_cast <;> apply zero_le
412
import Mathlib.MeasureTheory.Measure.Content import Mathlib.MeasureTheory.Group.Prod import Mathlib.Topology.Algebra.Group.Compact #align_import measure_theory.measure.haar.basic from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" noncomputable section open Set Inv Function TopologicalSpace MeasurableSpace open scoped NNReal Classical ENNReal Pointwise Topology namespace MeasureTheory namespace Measure section Group variable {G : Type*} [Group G] namespace haar -- Porting note: Even in `noncomputable section`, a definition with `to_additive` require -- `noncomputable` to generate an additive definition. -- Please refer to leanprover/lean4#2077. @[to_additive addIndex "additive version of `MeasureTheory.Measure.haar.index`"] noncomputable def index (K V : Set G) : ℕ := sInf <| Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } #align measure_theory.measure.haar.index MeasureTheory.Measure.haar.index #align measure_theory.measure.haar.add_index MeasureTheory.Measure.haar.addIndex @[to_additive addIndex_empty] theorem index_empty {V : Set G} : index ∅ V = 0 := by simp only [index, Nat.sInf_eq_zero]; left; use ∅ simp only [Finset.card_empty, empty_subset, mem_setOf_eq, eq_self_iff_true, and_self_iff] #align measure_theory.measure.haar.index_empty MeasureTheory.Measure.haar.index_empty #align measure_theory.measure.haar.add_index_empty MeasureTheory.Measure.haar.addIndex_empty variable [TopologicalSpace G] @[to_additive "additive version of `MeasureTheory.Measure.haar.prehaar`"] noncomputable def prehaar (K₀ U : Set G) (K : Compacts G) : ℝ := (index (K : Set G) U : ℝ) / index K₀ U #align measure_theory.measure.haar.prehaar MeasureTheory.Measure.haar.prehaar #align measure_theory.measure.haar.add_prehaar MeasureTheory.Measure.haar.addPrehaar @[to_additive] theorem prehaar_empty (K₀ : PositiveCompacts G) {U : Set G} : prehaar (K₀ : Set G) U ⊥ = 0 := by rw [prehaar, Compacts.coe_bot, index_empty, Nat.cast_zero, zero_div] #align measure_theory.measure.haar.prehaar_empty MeasureTheory.Measure.haar.prehaar_empty #align measure_theory.measure.haar.add_prehaar_empty MeasureTheory.Measure.haar.addPrehaar_empty @[to_additive] theorem prehaar_nonneg (K₀ : PositiveCompacts G) {U : Set G} (K : Compacts G) : 0 ≤ prehaar (K₀ : Set G) U K := by apply div_nonneg <;> norm_cast <;> apply zero_le #align measure_theory.measure.haar.prehaar_nonneg MeasureTheory.Measure.haar.prehaar_nonneg #align measure_theory.measure.haar.add_prehaar_nonneg MeasureTheory.Measure.haar.addPrehaar_nonneg @[to_additive "additive version of `MeasureTheory.Measure.haar.haarProduct`"] def haarProduct (K₀ : Set G) : Set (Compacts G → ℝ) := pi univ fun K => Icc 0 <| index (K : Set G) K₀ #align measure_theory.measure.haar.haar_product MeasureTheory.Measure.haar.haarProduct #align measure_theory.measure.haar.add_haar_product MeasureTheory.Measure.haar.addHaarProduct @[to_additive (attr := simp)]
Mathlib/MeasureTheory/Measure/Haar/Basic.lean
142
144
theorem mem_prehaar_empty {K₀ : Set G} {f : Compacts G → ℝ} : f ∈ haarProduct K₀ ↔ ∀ K : Compacts G, f K ∈ Icc (0 : ℝ) (index (K : Set G) K₀) := by
simp only [haarProduct, Set.pi, forall_prop_of_true, mem_univ, mem_setOf_eq]
412
import Mathlib.MeasureTheory.Measure.Content import Mathlib.MeasureTheory.Group.Prod import Mathlib.Topology.Algebra.Group.Compact #align_import measure_theory.measure.haar.basic from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" noncomputable section open Set Inv Function TopologicalSpace MeasurableSpace open scoped NNReal Classical ENNReal Pointwise Topology namespace MeasureTheory namespace Measure section Group variable {G : Type*} [Group G] namespace haar -- Porting note: Even in `noncomputable section`, a definition with `to_additive` require -- `noncomputable` to generate an additive definition. -- Please refer to leanprover/lean4#2077. @[to_additive addIndex "additive version of `MeasureTheory.Measure.haar.index`"] noncomputable def index (K V : Set G) : ℕ := sInf <| Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } #align measure_theory.measure.haar.index MeasureTheory.Measure.haar.index #align measure_theory.measure.haar.add_index MeasureTheory.Measure.haar.addIndex @[to_additive addIndex_empty] theorem index_empty {V : Set G} : index ∅ V = 0 := by simp only [index, Nat.sInf_eq_zero]; left; use ∅ simp only [Finset.card_empty, empty_subset, mem_setOf_eq, eq_self_iff_true, and_self_iff] #align measure_theory.measure.haar.index_empty MeasureTheory.Measure.haar.index_empty #align measure_theory.measure.haar.add_index_empty MeasureTheory.Measure.haar.addIndex_empty variable [TopologicalSpace G] @[to_additive "additive version of `MeasureTheory.Measure.haar.prehaar`"] noncomputable def prehaar (K₀ U : Set G) (K : Compacts G) : ℝ := (index (K : Set G) U : ℝ) / index K₀ U #align measure_theory.measure.haar.prehaar MeasureTheory.Measure.haar.prehaar #align measure_theory.measure.haar.add_prehaar MeasureTheory.Measure.haar.addPrehaar @[to_additive] theorem prehaar_empty (K₀ : PositiveCompacts G) {U : Set G} : prehaar (K₀ : Set G) U ⊥ = 0 := by rw [prehaar, Compacts.coe_bot, index_empty, Nat.cast_zero, zero_div] #align measure_theory.measure.haar.prehaar_empty MeasureTheory.Measure.haar.prehaar_empty #align measure_theory.measure.haar.add_prehaar_empty MeasureTheory.Measure.haar.addPrehaar_empty @[to_additive] theorem prehaar_nonneg (K₀ : PositiveCompacts G) {U : Set G} (K : Compacts G) : 0 ≤ prehaar (K₀ : Set G) U K := by apply div_nonneg <;> norm_cast <;> apply zero_le #align measure_theory.measure.haar.prehaar_nonneg MeasureTheory.Measure.haar.prehaar_nonneg #align measure_theory.measure.haar.add_prehaar_nonneg MeasureTheory.Measure.haar.addPrehaar_nonneg @[to_additive "additive version of `MeasureTheory.Measure.haar.haarProduct`"] def haarProduct (K₀ : Set G) : Set (Compacts G → ℝ) := pi univ fun K => Icc 0 <| index (K : Set G) K₀ #align measure_theory.measure.haar.haar_product MeasureTheory.Measure.haar.haarProduct #align measure_theory.measure.haar.add_haar_product MeasureTheory.Measure.haar.addHaarProduct @[to_additive (attr := simp)] theorem mem_prehaar_empty {K₀ : Set G} {f : Compacts G → ℝ} : f ∈ haarProduct K₀ ↔ ∀ K : Compacts G, f K ∈ Icc (0 : ℝ) (index (K : Set G) K₀) := by simp only [haarProduct, Set.pi, forall_prop_of_true, mem_univ, mem_setOf_eq] #align measure_theory.measure.haar.mem_prehaar_empty MeasureTheory.Measure.haar.mem_prehaar_empty #align measure_theory.measure.haar.mem_add_prehaar_empty MeasureTheory.Measure.haar.mem_addPrehaar_empty @[to_additive "additive version of `MeasureTheory.Measure.haar.clPrehaar`"] def clPrehaar (K₀ : Set G) (V : OpenNhdsOf (1 : G)) : Set (Compacts G → ℝ) := closure <| prehaar K₀ '' { U : Set G | U ⊆ V.1 ∧ IsOpen U ∧ (1 : G) ∈ U } #align measure_theory.measure.haar.cl_prehaar MeasureTheory.Measure.haar.clPrehaar #align measure_theory.measure.haar.cl_add_prehaar MeasureTheory.Measure.haar.clAddPrehaar variable [TopologicalGroup G] @[to_additive addIndex_defined "If `K` is compact and `V` has nonempty interior, then the index `(K : V)` is well-defined, there is a finite set `t` satisfying the desired properties."]
Mathlib/MeasureTheory/Measure/Haar/Basic.lean
171
173
theorem index_defined {K V : Set G} (hK : IsCompact K) (hV : (interior V).Nonempty) : ∃ n : ℕ, n ∈ Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } := by
rcases compact_covered_by_mul_left_translates hK hV with ⟨t, ht⟩; exact ⟨t.card, t, ht, rfl⟩
412
import Mathlib.MeasureTheory.Measure.Content import Mathlib.MeasureTheory.Group.Prod import Mathlib.Topology.Algebra.Group.Compact #align_import measure_theory.measure.haar.basic from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" noncomputable section open Set Inv Function TopologicalSpace MeasurableSpace open scoped NNReal Classical ENNReal Pointwise Topology namespace MeasureTheory namespace Measure section Group variable {G : Type*} [Group G] namespace haar -- Porting note: Even in `noncomputable section`, a definition with `to_additive` require -- `noncomputable` to generate an additive definition. -- Please refer to leanprover/lean4#2077. @[to_additive addIndex "additive version of `MeasureTheory.Measure.haar.index`"] noncomputable def index (K V : Set G) : ℕ := sInf <| Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } #align measure_theory.measure.haar.index MeasureTheory.Measure.haar.index #align measure_theory.measure.haar.add_index MeasureTheory.Measure.haar.addIndex @[to_additive addIndex_empty] theorem index_empty {V : Set G} : index ∅ V = 0 := by simp only [index, Nat.sInf_eq_zero]; left; use ∅ simp only [Finset.card_empty, empty_subset, mem_setOf_eq, eq_self_iff_true, and_self_iff] #align measure_theory.measure.haar.index_empty MeasureTheory.Measure.haar.index_empty #align measure_theory.measure.haar.add_index_empty MeasureTheory.Measure.haar.addIndex_empty variable [TopologicalSpace G] @[to_additive "additive version of `MeasureTheory.Measure.haar.prehaar`"] noncomputable def prehaar (K₀ U : Set G) (K : Compacts G) : ℝ := (index (K : Set G) U : ℝ) / index K₀ U #align measure_theory.measure.haar.prehaar MeasureTheory.Measure.haar.prehaar #align measure_theory.measure.haar.add_prehaar MeasureTheory.Measure.haar.addPrehaar @[to_additive] theorem prehaar_empty (K₀ : PositiveCompacts G) {U : Set G} : prehaar (K₀ : Set G) U ⊥ = 0 := by rw [prehaar, Compacts.coe_bot, index_empty, Nat.cast_zero, zero_div] #align measure_theory.measure.haar.prehaar_empty MeasureTheory.Measure.haar.prehaar_empty #align measure_theory.measure.haar.add_prehaar_empty MeasureTheory.Measure.haar.addPrehaar_empty @[to_additive] theorem prehaar_nonneg (K₀ : PositiveCompacts G) {U : Set G} (K : Compacts G) : 0 ≤ prehaar (K₀ : Set G) U K := by apply div_nonneg <;> norm_cast <;> apply zero_le #align measure_theory.measure.haar.prehaar_nonneg MeasureTheory.Measure.haar.prehaar_nonneg #align measure_theory.measure.haar.add_prehaar_nonneg MeasureTheory.Measure.haar.addPrehaar_nonneg @[to_additive "additive version of `MeasureTheory.Measure.haar.haarProduct`"] def haarProduct (K₀ : Set G) : Set (Compacts G → ℝ) := pi univ fun K => Icc 0 <| index (K : Set G) K₀ #align measure_theory.measure.haar.haar_product MeasureTheory.Measure.haar.haarProduct #align measure_theory.measure.haar.add_haar_product MeasureTheory.Measure.haar.addHaarProduct @[to_additive (attr := simp)] theorem mem_prehaar_empty {K₀ : Set G} {f : Compacts G → ℝ} : f ∈ haarProduct K₀ ↔ ∀ K : Compacts G, f K ∈ Icc (0 : ℝ) (index (K : Set G) K₀) := by simp only [haarProduct, Set.pi, forall_prop_of_true, mem_univ, mem_setOf_eq] #align measure_theory.measure.haar.mem_prehaar_empty MeasureTheory.Measure.haar.mem_prehaar_empty #align measure_theory.measure.haar.mem_add_prehaar_empty MeasureTheory.Measure.haar.mem_addPrehaar_empty @[to_additive "additive version of `MeasureTheory.Measure.haar.clPrehaar`"] def clPrehaar (K₀ : Set G) (V : OpenNhdsOf (1 : G)) : Set (Compacts G → ℝ) := closure <| prehaar K₀ '' { U : Set G | U ⊆ V.1 ∧ IsOpen U ∧ (1 : G) ∈ U } #align measure_theory.measure.haar.cl_prehaar MeasureTheory.Measure.haar.clPrehaar #align measure_theory.measure.haar.cl_add_prehaar MeasureTheory.Measure.haar.clAddPrehaar variable [TopologicalGroup G] @[to_additive addIndex_defined "If `K` is compact and `V` has nonempty interior, then the index `(K : V)` is well-defined, there is a finite set `t` satisfying the desired properties."] theorem index_defined {K V : Set G} (hK : IsCompact K) (hV : (interior V).Nonempty) : ∃ n : ℕ, n ∈ Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } := by rcases compact_covered_by_mul_left_translates hK hV with ⟨t, ht⟩; exact ⟨t.card, t, ht, rfl⟩ #align measure_theory.measure.haar.index_defined MeasureTheory.Measure.haar.index_defined #align measure_theory.measure.haar.add_index_defined MeasureTheory.Measure.haar.addIndex_defined @[to_additive addIndex_elim]
Mathlib/MeasureTheory/Measure/Haar/Basic.lean
178
180
theorem index_elim {K V : Set G} (hK : IsCompact K) (hV : (interior V).Nonempty) : ∃ t : Finset G, (K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V) ∧ Finset.card t = index K V := by
have := Nat.sInf_mem (index_defined hK hV); rwa [mem_image] at this
412
import Mathlib.MeasureTheory.Measure.Content import Mathlib.MeasureTheory.Group.Prod import Mathlib.Topology.Algebra.Group.Compact #align_import measure_theory.measure.haar.basic from "leanprover-community/mathlib"@"fd5edc43dc4f10b85abfe544b88f82cf13c5f844" noncomputable section open Set Inv Function TopologicalSpace MeasurableSpace open scoped NNReal Classical ENNReal Pointwise Topology namespace MeasureTheory namespace Measure section Group variable {G : Type*} [Group G] namespace haar -- Porting note: Even in `noncomputable section`, a definition with `to_additive` require -- `noncomputable` to generate an additive definition. -- Please refer to leanprover/lean4#2077. @[to_additive addIndex "additive version of `MeasureTheory.Measure.haar.index`"] noncomputable def index (K V : Set G) : ℕ := sInf <| Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } #align measure_theory.measure.haar.index MeasureTheory.Measure.haar.index #align measure_theory.measure.haar.add_index MeasureTheory.Measure.haar.addIndex @[to_additive addIndex_empty] theorem index_empty {V : Set G} : index ∅ V = 0 := by simp only [index, Nat.sInf_eq_zero]; left; use ∅ simp only [Finset.card_empty, empty_subset, mem_setOf_eq, eq_self_iff_true, and_self_iff] #align measure_theory.measure.haar.index_empty MeasureTheory.Measure.haar.index_empty #align measure_theory.measure.haar.add_index_empty MeasureTheory.Measure.haar.addIndex_empty variable [TopologicalSpace G] @[to_additive "additive version of `MeasureTheory.Measure.haar.prehaar`"] noncomputable def prehaar (K₀ U : Set G) (K : Compacts G) : ℝ := (index (K : Set G) U : ℝ) / index K₀ U #align measure_theory.measure.haar.prehaar MeasureTheory.Measure.haar.prehaar #align measure_theory.measure.haar.add_prehaar MeasureTheory.Measure.haar.addPrehaar @[to_additive] theorem prehaar_empty (K₀ : PositiveCompacts G) {U : Set G} : prehaar (K₀ : Set G) U ⊥ = 0 := by rw [prehaar, Compacts.coe_bot, index_empty, Nat.cast_zero, zero_div] #align measure_theory.measure.haar.prehaar_empty MeasureTheory.Measure.haar.prehaar_empty #align measure_theory.measure.haar.add_prehaar_empty MeasureTheory.Measure.haar.addPrehaar_empty @[to_additive] theorem prehaar_nonneg (K₀ : PositiveCompacts G) {U : Set G} (K : Compacts G) : 0 ≤ prehaar (K₀ : Set G) U K := by apply div_nonneg <;> norm_cast <;> apply zero_le #align measure_theory.measure.haar.prehaar_nonneg MeasureTheory.Measure.haar.prehaar_nonneg #align measure_theory.measure.haar.add_prehaar_nonneg MeasureTheory.Measure.haar.addPrehaar_nonneg @[to_additive "additive version of `MeasureTheory.Measure.haar.haarProduct`"] def haarProduct (K₀ : Set G) : Set (Compacts G → ℝ) := pi univ fun K => Icc 0 <| index (K : Set G) K₀ #align measure_theory.measure.haar.haar_product MeasureTheory.Measure.haar.haarProduct #align measure_theory.measure.haar.add_haar_product MeasureTheory.Measure.haar.addHaarProduct @[to_additive (attr := simp)] theorem mem_prehaar_empty {K₀ : Set G} {f : Compacts G → ℝ} : f ∈ haarProduct K₀ ↔ ∀ K : Compacts G, f K ∈ Icc (0 : ℝ) (index (K : Set G) K₀) := by simp only [haarProduct, Set.pi, forall_prop_of_true, mem_univ, mem_setOf_eq] #align measure_theory.measure.haar.mem_prehaar_empty MeasureTheory.Measure.haar.mem_prehaar_empty #align measure_theory.measure.haar.mem_add_prehaar_empty MeasureTheory.Measure.haar.mem_addPrehaar_empty @[to_additive "additive version of `MeasureTheory.Measure.haar.clPrehaar`"] def clPrehaar (K₀ : Set G) (V : OpenNhdsOf (1 : G)) : Set (Compacts G → ℝ) := closure <| prehaar K₀ '' { U : Set G | U ⊆ V.1 ∧ IsOpen U ∧ (1 : G) ∈ U } #align measure_theory.measure.haar.cl_prehaar MeasureTheory.Measure.haar.clPrehaar #align measure_theory.measure.haar.cl_add_prehaar MeasureTheory.Measure.haar.clAddPrehaar variable [TopologicalGroup G] @[to_additive addIndex_defined "If `K` is compact and `V` has nonempty interior, then the index `(K : V)` is well-defined, there is a finite set `t` satisfying the desired properties."] theorem index_defined {K V : Set G} (hK : IsCompact K) (hV : (interior V).Nonempty) : ∃ n : ℕ, n ∈ Finset.card '' { t : Finset G | K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V } := by rcases compact_covered_by_mul_left_translates hK hV with ⟨t, ht⟩; exact ⟨t.card, t, ht, rfl⟩ #align measure_theory.measure.haar.index_defined MeasureTheory.Measure.haar.index_defined #align measure_theory.measure.haar.add_index_defined MeasureTheory.Measure.haar.addIndex_defined @[to_additive addIndex_elim] theorem index_elim {K V : Set G} (hK : IsCompact K) (hV : (interior V).Nonempty) : ∃ t : Finset G, (K ⊆ ⋃ g ∈ t, (fun h => g * h) ⁻¹' V) ∧ Finset.card t = index K V := by have := Nat.sInf_mem (index_defined hK hV); rwa [mem_image] at this #align measure_theory.measure.haar.index_elim MeasureTheory.Measure.haar.index_elim #align measure_theory.measure.haar.add_index_elim MeasureTheory.Measure.haar.addIndex_elim @[to_additive le_addIndex_mul]
Mathlib/MeasureTheory/Measure/Haar/Basic.lean
185
196
theorem le_index_mul (K₀ : PositiveCompacts G) (K : Compacts G) {V : Set G} (hV : (interior V).Nonempty) : index (K : Set G) V ≤ index (K : Set G) K₀ * index (K₀ : Set G) V := by
obtain ⟨s, h1s, h2s⟩ := index_elim K.isCompact K₀.interior_nonempty obtain ⟨t, h1t, h2t⟩ := index_elim K₀.isCompact hV rw [← h2s, ← h2t, mul_comm] refine le_trans ?_ Finset.card_mul_le apply Nat.sInf_le; refine ⟨_, ?_, rfl⟩; rw [mem_setOf_eq]; refine Subset.trans h1s ?_ apply iUnion₂_subset; intro g₁ hg₁; rw [preimage_subset_iff]; intro g₂ hg₂ have := h1t hg₂ rcases this with ⟨_, ⟨g₃, rfl⟩, A, ⟨hg₃, rfl⟩, h2V⟩; rw [mem_preimage, ← mul_assoc] at h2V exact mem_biUnion (Finset.mul_mem_mul hg₃ hg₁) h2V
412
import Mathlib.Algebra.MvPolynomial.Supported import Mathlib.RingTheory.Derivation.Basic #align_import data.mv_polynomial.derivation from "leanprover-community/mathlib"@"b608348ffaeb7f557f2fd46876037abafd326ff3" namespace MvPolynomial noncomputable section variable {σ R A : Type*} [CommSemiring R] [AddCommMonoid A] [Module R A] [Module (MvPolynomial σ R) A] section variable (R) def mkDerivationₗ (f : σ → A) : MvPolynomial σ R →ₗ[R] A := Finsupp.lsum R fun xs : σ →₀ ℕ => (LinearMap.ringLmapEquivSelf R R A).symm <| xs.sum fun i k => monomial (xs - Finsupp.single i 1) (k : R) • f i #align mv_polynomial.mk_derivationₗ MvPolynomial.mkDerivationₗ end theorem mkDerivationₗ_monomial (f : σ → A) (s : σ →₀ ℕ) (r : R) : mkDerivationₗ R f (monomial s r) = r • s.sum fun i k => monomial (s - Finsupp.single i 1) (k : R) • f i := sum_monomial_eq <| LinearMap.map_zero _ #align mv_polynomial.mk_derivationₗ_monomial MvPolynomial.mkDerivationₗ_monomial theorem mkDerivationₗ_C (f : σ → A) (r : R) : mkDerivationₗ R f (C r) = 0 := (mkDerivationₗ_monomial f _ _).trans (smul_zero _) set_option linter.uppercaseLean3 false in #align mv_polynomial.mk_derivationₗ_C MvPolynomial.mkDerivationₗ_C theorem mkDerivationₗ_X (f : σ → A) (i : σ) : mkDerivationₗ R f (X i) = f i := (mkDerivationₗ_monomial f _ _).trans <| by simp set_option linter.uppercaseLean3 false in #align mv_polynomial.mk_derivationₗ_X MvPolynomial.mkDerivationₗ_X @[simp] theorem derivation_C (D : Derivation R (MvPolynomial σ R) A) (a : R) : D (C a) = 0 := D.map_algebraMap a set_option linter.uppercaseLean3 false in #align mv_polynomial.derivation_C MvPolynomial.derivation_C @[simp]
Mathlib/Algebra/MvPolynomial/Derivation.lean
65
68
theorem derivation_C_mul (D : Derivation R (MvPolynomial σ R) A) (a : R) (f : MvPolynomial σ R) : C (σ := σ) a • D f = a • D f := by
have : C (σ := σ) a • D f = D (C a * f) := by simp rw [this, C_mul', D.map_smul]
413
import Mathlib.Algebra.MvPolynomial.Supported import Mathlib.RingTheory.Derivation.Basic #align_import data.mv_polynomial.derivation from "leanprover-community/mathlib"@"b608348ffaeb7f557f2fd46876037abafd326ff3" namespace MvPolynomial noncomputable section variable {σ R A : Type*} [CommSemiring R] [AddCommMonoid A] [Module R A] [Module (MvPolynomial σ R) A] section variable (R) def mkDerivationₗ (f : σ → A) : MvPolynomial σ R →ₗ[R] A := Finsupp.lsum R fun xs : σ →₀ ℕ => (LinearMap.ringLmapEquivSelf R R A).symm <| xs.sum fun i k => monomial (xs - Finsupp.single i 1) (k : R) • f i #align mv_polynomial.mk_derivationₗ MvPolynomial.mkDerivationₗ end theorem mkDerivationₗ_monomial (f : σ → A) (s : σ →₀ ℕ) (r : R) : mkDerivationₗ R f (monomial s r) = r • s.sum fun i k => monomial (s - Finsupp.single i 1) (k : R) • f i := sum_monomial_eq <| LinearMap.map_zero _ #align mv_polynomial.mk_derivationₗ_monomial MvPolynomial.mkDerivationₗ_monomial theorem mkDerivationₗ_C (f : σ → A) (r : R) : mkDerivationₗ R f (C r) = 0 := (mkDerivationₗ_monomial f _ _).trans (smul_zero _) set_option linter.uppercaseLean3 false in #align mv_polynomial.mk_derivationₗ_C MvPolynomial.mkDerivationₗ_C theorem mkDerivationₗ_X (f : σ → A) (i : σ) : mkDerivationₗ R f (X i) = f i := (mkDerivationₗ_monomial f _ _).trans <| by simp set_option linter.uppercaseLean3 false in #align mv_polynomial.mk_derivationₗ_X MvPolynomial.mkDerivationₗ_X @[simp] theorem derivation_C (D : Derivation R (MvPolynomial σ R) A) (a : R) : D (C a) = 0 := D.map_algebraMap a set_option linter.uppercaseLean3 false in #align mv_polynomial.derivation_C MvPolynomial.derivation_C @[simp] theorem derivation_C_mul (D : Derivation R (MvPolynomial σ R) A) (a : R) (f : MvPolynomial σ R) : C (σ := σ) a • D f = a • D f := by have : C (σ := σ) a • D f = D (C a * f) := by simp rw [this, C_mul', D.map_smul] theorem derivation_eqOn_supported {D₁ D₂ : Derivation R (MvPolynomial σ R) A} {s : Set σ} (h : Set.EqOn (D₁ ∘ X) (D₂ ∘ X) s) {f : MvPolynomial σ R} (hf : f ∈ supported R s) : D₁ f = D₂ f := Derivation.eqOn_adjoin (Set.forall_mem_image.2 h) hf #align mv_polynomial.derivation_eq_on_supported MvPolynomial.derivation_eqOn_supported theorem derivation_eq_of_forall_mem_vars {D₁ D₂ : Derivation R (MvPolynomial σ R) A} {f : MvPolynomial σ R} (h : ∀ i ∈ f.vars, D₁ (X i) = D₂ (X i)) : D₁ f = D₂ f := derivation_eqOn_supported h f.mem_supported_vars #align mv_polynomial.derivation_eq_of_forall_mem_vars MvPolynomial.derivation_eq_of_forall_mem_vars theorem derivation_eq_zero_of_forall_mem_vars {D : Derivation R (MvPolynomial σ R) A} {f : MvPolynomial σ R} (h : ∀ i ∈ f.vars, D (X i) = 0) : D f = 0 := show D f = (0 : Derivation R (MvPolynomial σ R) A) f from derivation_eq_of_forall_mem_vars h #align mv_polynomial.derivation_eq_zero_of_forall_mem_vars MvPolynomial.derivation_eq_zero_of_forall_mem_vars @[ext] theorem derivation_ext {D₁ D₂ : Derivation R (MvPolynomial σ R) A} (h : ∀ i, D₁ (X i) = D₂ (X i)) : D₁ = D₂ := Derivation.ext fun _ => derivation_eq_of_forall_mem_vars fun i _ => h i #align mv_polynomial.derivation_ext MvPolynomial.derivation_ext variable [IsScalarTower R (MvPolynomial σ R) A]
Mathlib/Algebra/MvPolynomial/Derivation.lean
96
114
theorem leibniz_iff_X (D : MvPolynomial σ R →ₗ[R] A) (h₁ : D 1 = 0) : (∀ p q, D (p * q) = p • D q + q • D p) ↔ ∀ s i, D (monomial s 1 * X i) = (monomial s 1 : MvPolynomial σ R) • D (X i) + (X i : MvPolynomial σ R) • D (monomial s 1) := by
refine ⟨fun H p i => H _ _, fun H => ?_⟩ have hC : ∀ r, D (C r) = 0 := by intro r; rw [C_eq_smul_one, D.map_smul, h₁, smul_zero] have : ∀ p i, D (p * X i) = p • D (X i) + (X i : MvPolynomial σ R) • D p := by intro p i induction' p using MvPolynomial.induction_on' with s r p q hp hq · rw [← mul_one r, ← C_mul_monomial, mul_assoc, C_mul', D.map_smul, H, C_mul', smul_assoc, smul_add, D.map_smul, smul_comm r (X i)] · rw [add_mul, map_add, map_add, hp, hq, add_smul, smul_add, add_add_add_comm] intro p q induction q using MvPolynomial.induction_on with | h_C c => rw [mul_comm, C_mul', hC, smul_zero, zero_add, D.map_smul, C_eq_smul_one, smul_one_smul] | h_add q₁ q₂ h₁ h₂ => simp only [mul_add, map_add, h₁, h₂, smul_add, add_smul]; abel | h_X q i hq => simp only [this, ← mul_assoc, hq, mul_smul, smul_add, add_assoc] rw [smul_comm (X i), smul_comm (X i)]
413
import Mathlib.Algebra.MvPolynomial.Derivation import Mathlib.Algebra.MvPolynomial.Variables #align_import data.mv_polynomial.pderiv from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section universe u v namespace MvPolynomial open Set Function Finsupp variable {R : Type u} {σ : Type v} {a a' a₁ a₂ : R} {s : σ →₀ ℕ} section PDeriv variable [CommSemiring R] def pderiv (i : σ) : Derivation R (MvPolynomial σ R) (MvPolynomial σ R) := letI := Classical.decEq σ mkDerivation R <| Pi.single i 1 #align mv_polynomial.pderiv MvPolynomial.pderiv
Mathlib/Algebra/MvPolynomial/PDeriv.lean
64
65
theorem pderiv_def [DecidableEq σ] (i : σ) : pderiv i = mkDerivation R (Pi.single i 1) := by
unfold pderiv; congr!
414
import Mathlib.Algebra.MvPolynomial.Derivation import Mathlib.Algebra.MvPolynomial.Variables #align_import data.mv_polynomial.pderiv from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section universe u v namespace MvPolynomial open Set Function Finsupp variable {R : Type u} {σ : Type v} {a a' a₁ a₂ : R} {s : σ →₀ ℕ} section PDeriv variable [CommSemiring R] def pderiv (i : σ) : Derivation R (MvPolynomial σ R) (MvPolynomial σ R) := letI := Classical.decEq σ mkDerivation R <| Pi.single i 1 #align mv_polynomial.pderiv MvPolynomial.pderiv theorem pderiv_def [DecidableEq σ] (i : σ) : pderiv i = mkDerivation R (Pi.single i 1) := by unfold pderiv; congr! #align mv_polynomial.pderiv_def MvPolynomial.pderiv_def @[simp]
Mathlib/Algebra/MvPolynomial/PDeriv.lean
69
77
theorem pderiv_monomial {i : σ} : pderiv i (monomial s a) = monomial (s - single i 1) (a * s i) := by
classical simp only [pderiv_def, mkDerivation_monomial, Finsupp.smul_sum, smul_eq_mul, ← smul_mul_assoc, ← (monomial _).map_smul] refine (Finset.sum_eq_single i (fun j _ hne => ?_) fun hi => ?_).trans ?_ · simp [Pi.single_eq_of_ne hne] · rw [Finsupp.not_mem_support_iff] at hi; simp [hi] · simp
414
import Mathlib.Algebra.MvPolynomial.Derivation import Mathlib.Algebra.MvPolynomial.Variables #align_import data.mv_polynomial.pderiv from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section universe u v namespace MvPolynomial open Set Function Finsupp variable {R : Type u} {σ : Type v} {a a' a₁ a₂ : R} {s : σ →₀ ℕ} section PDeriv variable [CommSemiring R] def pderiv (i : σ) : Derivation R (MvPolynomial σ R) (MvPolynomial σ R) := letI := Classical.decEq σ mkDerivation R <| Pi.single i 1 #align mv_polynomial.pderiv MvPolynomial.pderiv theorem pderiv_def [DecidableEq σ] (i : σ) : pderiv i = mkDerivation R (Pi.single i 1) := by unfold pderiv; congr! #align mv_polynomial.pderiv_def MvPolynomial.pderiv_def @[simp] theorem pderiv_monomial {i : σ} : pderiv i (monomial s a) = monomial (s - single i 1) (a * s i) := by classical simp only [pderiv_def, mkDerivation_monomial, Finsupp.smul_sum, smul_eq_mul, ← smul_mul_assoc, ← (monomial _).map_smul] refine (Finset.sum_eq_single i (fun j _ hne => ?_) fun hi => ?_).trans ?_ · simp [Pi.single_eq_of_ne hne] · rw [Finsupp.not_mem_support_iff] at hi; simp [hi] · simp #align mv_polynomial.pderiv_monomial MvPolynomial.pderiv_monomial theorem pderiv_C {i : σ} : pderiv i (C a) = 0 := derivation_C _ _ set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_C MvPolynomial.pderiv_C theorem pderiv_one {i : σ} : pderiv i (1 : MvPolynomial σ R) = 0 := pderiv_C #align mv_polynomial.pderiv_one MvPolynomial.pderiv_one @[simp]
Mathlib/Algebra/MvPolynomial/PDeriv.lean
89
91
theorem pderiv_X [DecidableEq σ] (i j : σ) : pderiv i (X j : MvPolynomial σ R) = Pi.single (f := fun j => _) i 1 j := by
rw [pderiv_def, mkDerivation_X]
414
import Mathlib.Algebra.MvPolynomial.Derivation import Mathlib.Algebra.MvPolynomial.Variables #align_import data.mv_polynomial.pderiv from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section universe u v namespace MvPolynomial open Set Function Finsupp variable {R : Type u} {σ : Type v} {a a' a₁ a₂ : R} {s : σ →₀ ℕ} section PDeriv variable [CommSemiring R] def pderiv (i : σ) : Derivation R (MvPolynomial σ R) (MvPolynomial σ R) := letI := Classical.decEq σ mkDerivation R <| Pi.single i 1 #align mv_polynomial.pderiv MvPolynomial.pderiv theorem pderiv_def [DecidableEq σ] (i : σ) : pderiv i = mkDerivation R (Pi.single i 1) := by unfold pderiv; congr! #align mv_polynomial.pderiv_def MvPolynomial.pderiv_def @[simp] theorem pderiv_monomial {i : σ} : pderiv i (monomial s a) = monomial (s - single i 1) (a * s i) := by classical simp only [pderiv_def, mkDerivation_monomial, Finsupp.smul_sum, smul_eq_mul, ← smul_mul_assoc, ← (monomial _).map_smul] refine (Finset.sum_eq_single i (fun j _ hne => ?_) fun hi => ?_).trans ?_ · simp [Pi.single_eq_of_ne hne] · rw [Finsupp.not_mem_support_iff] at hi; simp [hi] · simp #align mv_polynomial.pderiv_monomial MvPolynomial.pderiv_monomial theorem pderiv_C {i : σ} : pderiv i (C a) = 0 := derivation_C _ _ set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_C MvPolynomial.pderiv_C theorem pderiv_one {i : σ} : pderiv i (1 : MvPolynomial σ R) = 0 := pderiv_C #align mv_polynomial.pderiv_one MvPolynomial.pderiv_one @[simp] theorem pderiv_X [DecidableEq σ] (i j : σ) : pderiv i (X j : MvPolynomial σ R) = Pi.single (f := fun j => _) i 1 j := by rw [pderiv_def, mkDerivation_X] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X MvPolynomial.pderiv_X @[simp]
Mathlib/Algebra/MvPolynomial/PDeriv.lean
96
96
theorem pderiv_X_self (i : σ) : pderiv i (X i : MvPolynomial σ R) = 1 := by
classical simp
414
import Mathlib.Algebra.MvPolynomial.Derivation import Mathlib.Algebra.MvPolynomial.Variables #align_import data.mv_polynomial.pderiv from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section universe u v namespace MvPolynomial open Set Function Finsupp variable {R : Type u} {σ : Type v} {a a' a₁ a₂ : R} {s : σ →₀ ℕ} section PDeriv variable [CommSemiring R] def pderiv (i : σ) : Derivation R (MvPolynomial σ R) (MvPolynomial σ R) := letI := Classical.decEq σ mkDerivation R <| Pi.single i 1 #align mv_polynomial.pderiv MvPolynomial.pderiv theorem pderiv_def [DecidableEq σ] (i : σ) : pderiv i = mkDerivation R (Pi.single i 1) := by unfold pderiv; congr! #align mv_polynomial.pderiv_def MvPolynomial.pderiv_def @[simp] theorem pderiv_monomial {i : σ} : pderiv i (monomial s a) = monomial (s - single i 1) (a * s i) := by classical simp only [pderiv_def, mkDerivation_monomial, Finsupp.smul_sum, smul_eq_mul, ← smul_mul_assoc, ← (monomial _).map_smul] refine (Finset.sum_eq_single i (fun j _ hne => ?_) fun hi => ?_).trans ?_ · simp [Pi.single_eq_of_ne hne] · rw [Finsupp.not_mem_support_iff] at hi; simp [hi] · simp #align mv_polynomial.pderiv_monomial MvPolynomial.pderiv_monomial theorem pderiv_C {i : σ} : pderiv i (C a) = 0 := derivation_C _ _ set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_C MvPolynomial.pderiv_C theorem pderiv_one {i : σ} : pderiv i (1 : MvPolynomial σ R) = 0 := pderiv_C #align mv_polynomial.pderiv_one MvPolynomial.pderiv_one @[simp] theorem pderiv_X [DecidableEq σ] (i j : σ) : pderiv i (X j : MvPolynomial σ R) = Pi.single (f := fun j => _) i 1 j := by rw [pderiv_def, mkDerivation_X] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X MvPolynomial.pderiv_X @[simp] theorem pderiv_X_self (i : σ) : pderiv i (X i : MvPolynomial σ R) = 1 := by classical simp set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X_self MvPolynomial.pderiv_X_self @[simp]
Mathlib/Algebra/MvPolynomial/PDeriv.lean
101
102
theorem pderiv_X_of_ne {i j : σ} (h : j ≠ i) : pderiv i (X j : MvPolynomial σ R) = 0 := by
classical simp [h]
414
import Mathlib.Algebra.MvPolynomial.Derivation import Mathlib.Algebra.MvPolynomial.Variables #align_import data.mv_polynomial.pderiv from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section universe u v namespace MvPolynomial open Set Function Finsupp variable {R : Type u} {σ : Type v} {a a' a₁ a₂ : R} {s : σ →₀ ℕ} section PDeriv variable [CommSemiring R] def pderiv (i : σ) : Derivation R (MvPolynomial σ R) (MvPolynomial σ R) := letI := Classical.decEq σ mkDerivation R <| Pi.single i 1 #align mv_polynomial.pderiv MvPolynomial.pderiv theorem pderiv_def [DecidableEq σ] (i : σ) : pderiv i = mkDerivation R (Pi.single i 1) := by unfold pderiv; congr! #align mv_polynomial.pderiv_def MvPolynomial.pderiv_def @[simp] theorem pderiv_monomial {i : σ} : pderiv i (monomial s a) = monomial (s - single i 1) (a * s i) := by classical simp only [pderiv_def, mkDerivation_monomial, Finsupp.smul_sum, smul_eq_mul, ← smul_mul_assoc, ← (monomial _).map_smul] refine (Finset.sum_eq_single i (fun j _ hne => ?_) fun hi => ?_).trans ?_ · simp [Pi.single_eq_of_ne hne] · rw [Finsupp.not_mem_support_iff] at hi; simp [hi] · simp #align mv_polynomial.pderiv_monomial MvPolynomial.pderiv_monomial theorem pderiv_C {i : σ} : pderiv i (C a) = 0 := derivation_C _ _ set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_C MvPolynomial.pderiv_C theorem pderiv_one {i : σ} : pderiv i (1 : MvPolynomial σ R) = 0 := pderiv_C #align mv_polynomial.pderiv_one MvPolynomial.pderiv_one @[simp] theorem pderiv_X [DecidableEq σ] (i j : σ) : pderiv i (X j : MvPolynomial σ R) = Pi.single (f := fun j => _) i 1 j := by rw [pderiv_def, mkDerivation_X] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X MvPolynomial.pderiv_X @[simp] theorem pderiv_X_self (i : σ) : pderiv i (X i : MvPolynomial σ R) = 1 := by classical simp set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X_self MvPolynomial.pderiv_X_self @[simp] theorem pderiv_X_of_ne {i j : σ} (h : j ≠ i) : pderiv i (X j : MvPolynomial σ R) = 0 := by classical simp [h] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X_of_ne MvPolynomial.pderiv_X_of_ne theorem pderiv_eq_zero_of_not_mem_vars {i : σ} {f : MvPolynomial σ R} (h : i ∉ f.vars) : pderiv i f = 0 := derivation_eq_zero_of_forall_mem_vars fun _ hj => pderiv_X_of_ne <| ne_of_mem_of_not_mem hj h #align mv_polynomial.pderiv_eq_zero_of_not_mem_vars MvPolynomial.pderiv_eq_zero_of_not_mem_vars
Mathlib/Algebra/MvPolynomial/PDeriv.lean
111
112
theorem pderiv_monomial_single {i : σ} {n : ℕ} : pderiv i (monomial (single i n) a) = monomial (single i (n - 1)) (a * n) := by
simp
414
import Mathlib.Algebra.MvPolynomial.Derivation import Mathlib.Algebra.MvPolynomial.Variables #align_import data.mv_polynomial.pderiv from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section universe u v namespace MvPolynomial open Set Function Finsupp variable {R : Type u} {σ : Type v} {a a' a₁ a₂ : R} {s : σ →₀ ℕ} section PDeriv variable [CommSemiring R] def pderiv (i : σ) : Derivation R (MvPolynomial σ R) (MvPolynomial σ R) := letI := Classical.decEq σ mkDerivation R <| Pi.single i 1 #align mv_polynomial.pderiv MvPolynomial.pderiv theorem pderiv_def [DecidableEq σ] (i : σ) : pderiv i = mkDerivation R (Pi.single i 1) := by unfold pderiv; congr! #align mv_polynomial.pderiv_def MvPolynomial.pderiv_def @[simp] theorem pderiv_monomial {i : σ} : pderiv i (monomial s a) = monomial (s - single i 1) (a * s i) := by classical simp only [pderiv_def, mkDerivation_monomial, Finsupp.smul_sum, smul_eq_mul, ← smul_mul_assoc, ← (monomial _).map_smul] refine (Finset.sum_eq_single i (fun j _ hne => ?_) fun hi => ?_).trans ?_ · simp [Pi.single_eq_of_ne hne] · rw [Finsupp.not_mem_support_iff] at hi; simp [hi] · simp #align mv_polynomial.pderiv_monomial MvPolynomial.pderiv_monomial theorem pderiv_C {i : σ} : pderiv i (C a) = 0 := derivation_C _ _ set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_C MvPolynomial.pderiv_C theorem pderiv_one {i : σ} : pderiv i (1 : MvPolynomial σ R) = 0 := pderiv_C #align mv_polynomial.pderiv_one MvPolynomial.pderiv_one @[simp] theorem pderiv_X [DecidableEq σ] (i j : σ) : pderiv i (X j : MvPolynomial σ R) = Pi.single (f := fun j => _) i 1 j := by rw [pderiv_def, mkDerivation_X] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X MvPolynomial.pderiv_X @[simp] theorem pderiv_X_self (i : σ) : pderiv i (X i : MvPolynomial σ R) = 1 := by classical simp set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X_self MvPolynomial.pderiv_X_self @[simp] theorem pderiv_X_of_ne {i j : σ} (h : j ≠ i) : pderiv i (X j : MvPolynomial σ R) = 0 := by classical simp [h] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X_of_ne MvPolynomial.pderiv_X_of_ne theorem pderiv_eq_zero_of_not_mem_vars {i : σ} {f : MvPolynomial σ R} (h : i ∉ f.vars) : pderiv i f = 0 := derivation_eq_zero_of_forall_mem_vars fun _ hj => pderiv_X_of_ne <| ne_of_mem_of_not_mem hj h #align mv_polynomial.pderiv_eq_zero_of_not_mem_vars MvPolynomial.pderiv_eq_zero_of_not_mem_vars theorem pderiv_monomial_single {i : σ} {n : ℕ} : pderiv i (monomial (single i n) a) = monomial (single i (n - 1)) (a * n) := by simp #align mv_polynomial.pderiv_monomial_single MvPolynomial.pderiv_monomial_single
Mathlib/Algebra/MvPolynomial/PDeriv.lean
115
117
theorem pderiv_mul {i : σ} {f g : MvPolynomial σ R} : pderiv i (f * g) = pderiv i f * g + f * pderiv i g := by
simp only [(pderiv i).leibniz f g, smul_eq_mul, mul_comm, add_comm]
414
import Mathlib.Algebra.MvPolynomial.Derivation import Mathlib.Algebra.MvPolynomial.Variables #align_import data.mv_polynomial.pderiv from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section universe u v namespace MvPolynomial open Set Function Finsupp variable {R : Type u} {σ : Type v} {a a' a₁ a₂ : R} {s : σ →₀ ℕ} section PDeriv variable [CommSemiring R] def pderiv (i : σ) : Derivation R (MvPolynomial σ R) (MvPolynomial σ R) := letI := Classical.decEq σ mkDerivation R <| Pi.single i 1 #align mv_polynomial.pderiv MvPolynomial.pderiv theorem pderiv_def [DecidableEq σ] (i : σ) : pderiv i = mkDerivation R (Pi.single i 1) := by unfold pderiv; congr! #align mv_polynomial.pderiv_def MvPolynomial.pderiv_def @[simp] theorem pderiv_monomial {i : σ} : pderiv i (monomial s a) = monomial (s - single i 1) (a * s i) := by classical simp only [pderiv_def, mkDerivation_monomial, Finsupp.smul_sum, smul_eq_mul, ← smul_mul_assoc, ← (monomial _).map_smul] refine (Finset.sum_eq_single i (fun j _ hne => ?_) fun hi => ?_).trans ?_ · simp [Pi.single_eq_of_ne hne] · rw [Finsupp.not_mem_support_iff] at hi; simp [hi] · simp #align mv_polynomial.pderiv_monomial MvPolynomial.pderiv_monomial theorem pderiv_C {i : σ} : pderiv i (C a) = 0 := derivation_C _ _ set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_C MvPolynomial.pderiv_C theorem pderiv_one {i : σ} : pderiv i (1 : MvPolynomial σ R) = 0 := pderiv_C #align mv_polynomial.pderiv_one MvPolynomial.pderiv_one @[simp] theorem pderiv_X [DecidableEq σ] (i j : σ) : pderiv i (X j : MvPolynomial σ R) = Pi.single (f := fun j => _) i 1 j := by rw [pderiv_def, mkDerivation_X] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X MvPolynomial.pderiv_X @[simp] theorem pderiv_X_self (i : σ) : pderiv i (X i : MvPolynomial σ R) = 1 := by classical simp set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X_self MvPolynomial.pderiv_X_self @[simp] theorem pderiv_X_of_ne {i j : σ} (h : j ≠ i) : pderiv i (X j : MvPolynomial σ R) = 0 := by classical simp [h] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X_of_ne MvPolynomial.pderiv_X_of_ne theorem pderiv_eq_zero_of_not_mem_vars {i : σ} {f : MvPolynomial σ R} (h : i ∉ f.vars) : pderiv i f = 0 := derivation_eq_zero_of_forall_mem_vars fun _ hj => pderiv_X_of_ne <| ne_of_mem_of_not_mem hj h #align mv_polynomial.pderiv_eq_zero_of_not_mem_vars MvPolynomial.pderiv_eq_zero_of_not_mem_vars theorem pderiv_monomial_single {i : σ} {n : ℕ} : pderiv i (monomial (single i n) a) = monomial (single i (n - 1)) (a * n) := by simp #align mv_polynomial.pderiv_monomial_single MvPolynomial.pderiv_monomial_single theorem pderiv_mul {i : σ} {f g : MvPolynomial σ R} : pderiv i (f * g) = pderiv i f * g + f * pderiv i g := by simp only [(pderiv i).leibniz f g, smul_eq_mul, mul_comm, add_comm] #align mv_polynomial.pderiv_mul MvPolynomial.pderiv_mul
Mathlib/Algebra/MvPolynomial/PDeriv.lean
120
122
theorem pderiv_pow {i : σ} {f : MvPolynomial σ R} {n : ℕ} : pderiv i (f ^ n) = n * f ^ (n - 1) * pderiv i f := by
rw [(pderiv i).leibniz_pow f n, nsmul_eq_mul, smul_eq_mul, mul_assoc]
414
import Mathlib.Algebra.MvPolynomial.Derivation import Mathlib.Algebra.MvPolynomial.Variables #align_import data.mv_polynomial.pderiv from "leanprover-community/mathlib"@"2f5b500a507264de86d666a5f87ddb976e2d8de4" noncomputable section universe u v namespace MvPolynomial open Set Function Finsupp variable {R : Type u} {σ : Type v} {a a' a₁ a₂ : R} {s : σ →₀ ℕ} section PDeriv variable [CommSemiring R] def pderiv (i : σ) : Derivation R (MvPolynomial σ R) (MvPolynomial σ R) := letI := Classical.decEq σ mkDerivation R <| Pi.single i 1 #align mv_polynomial.pderiv MvPolynomial.pderiv theorem pderiv_def [DecidableEq σ] (i : σ) : pderiv i = mkDerivation R (Pi.single i 1) := by unfold pderiv; congr! #align mv_polynomial.pderiv_def MvPolynomial.pderiv_def @[simp] theorem pderiv_monomial {i : σ} : pderiv i (monomial s a) = monomial (s - single i 1) (a * s i) := by classical simp only [pderiv_def, mkDerivation_monomial, Finsupp.smul_sum, smul_eq_mul, ← smul_mul_assoc, ← (monomial _).map_smul] refine (Finset.sum_eq_single i (fun j _ hne => ?_) fun hi => ?_).trans ?_ · simp [Pi.single_eq_of_ne hne] · rw [Finsupp.not_mem_support_iff] at hi; simp [hi] · simp #align mv_polynomial.pderiv_monomial MvPolynomial.pderiv_monomial theorem pderiv_C {i : σ} : pderiv i (C a) = 0 := derivation_C _ _ set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_C MvPolynomial.pderiv_C theorem pderiv_one {i : σ} : pderiv i (1 : MvPolynomial σ R) = 0 := pderiv_C #align mv_polynomial.pderiv_one MvPolynomial.pderiv_one @[simp] theorem pderiv_X [DecidableEq σ] (i j : σ) : pderiv i (X j : MvPolynomial σ R) = Pi.single (f := fun j => _) i 1 j := by rw [pderiv_def, mkDerivation_X] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X MvPolynomial.pderiv_X @[simp] theorem pderiv_X_self (i : σ) : pderiv i (X i : MvPolynomial σ R) = 1 := by classical simp set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X_self MvPolynomial.pderiv_X_self @[simp] theorem pderiv_X_of_ne {i j : σ} (h : j ≠ i) : pderiv i (X j : MvPolynomial σ R) = 0 := by classical simp [h] set_option linter.uppercaseLean3 false in #align mv_polynomial.pderiv_X_of_ne MvPolynomial.pderiv_X_of_ne theorem pderiv_eq_zero_of_not_mem_vars {i : σ} {f : MvPolynomial σ R} (h : i ∉ f.vars) : pderiv i f = 0 := derivation_eq_zero_of_forall_mem_vars fun _ hj => pderiv_X_of_ne <| ne_of_mem_of_not_mem hj h #align mv_polynomial.pderiv_eq_zero_of_not_mem_vars MvPolynomial.pderiv_eq_zero_of_not_mem_vars theorem pderiv_monomial_single {i : σ} {n : ℕ} : pderiv i (monomial (single i n) a) = monomial (single i (n - 1)) (a * n) := by simp #align mv_polynomial.pderiv_monomial_single MvPolynomial.pderiv_monomial_single theorem pderiv_mul {i : σ} {f g : MvPolynomial σ R} : pderiv i (f * g) = pderiv i f * g + f * pderiv i g := by simp only [(pderiv i).leibniz f g, smul_eq_mul, mul_comm, add_comm] #align mv_polynomial.pderiv_mul MvPolynomial.pderiv_mul theorem pderiv_pow {i : σ} {f : MvPolynomial σ R} {n : ℕ} : pderiv i (f ^ n) = n * f ^ (n - 1) * pderiv i f := by rw [(pderiv i).leibniz_pow f n, nsmul_eq_mul, smul_eq_mul, mul_assoc] -- @[simp] -- Porting note (#10618): simp can prove this
Mathlib/Algebra/MvPolynomial/PDeriv.lean
125
126
theorem pderiv_C_mul {f : MvPolynomial σ R} {i : σ} : pderiv i (C a * f) = C a * pderiv i f := by
rw [C_mul', Derivation.map_smul, C_mul']
414
import Mathlib.CategoryTheory.FinCategory.Basic import Mathlib.CategoryTheory.Limits.Cones import Mathlib.CategoryTheory.Limits.Shapes.FiniteLimits import Mathlib.CategoryTheory.Adjunction.Basic import Mathlib.CategoryTheory.Category.Preorder import Mathlib.CategoryTheory.Category.ULift import Mathlib.CategoryTheory.PEmpty #align_import category_theory.filtered from "leanprover-community/mathlib"@"14e80e85cbca5872a329fbfd3d1f3fd64e306934" open Function -- declare the `v`'s first; see `CategoryTheory.Category` for an explanation universe w v v₁ u u₁ u₂ namespace CategoryTheory variable (C : Type u) [Category.{v} C] class IsFilteredOrEmpty : Prop where cocone_objs : ∀ X Y : C, ∃ (Z : _) (_ : X ⟶ Z) (_ : Y ⟶ Z), True cocone_maps : ∀ ⦃X Y : C⦄ (f g : X ⟶ Y), ∃ (Z : _) (h : Y ⟶ Z), f ≫ h = g ≫ h #align category_theory.is_filtered_or_empty CategoryTheory.IsFilteredOrEmpty class IsFiltered extends IsFilteredOrEmpty C : Prop where [nonempty : Nonempty C] #align category_theory.is_filtered CategoryTheory.IsFiltered instance (priority := 100) isFilteredOrEmpty_of_semilatticeSup (α : Type u) [SemilatticeSup α] : IsFilteredOrEmpty α where cocone_objs X Y := ⟨X ⊔ Y, homOfLE le_sup_left, homOfLE le_sup_right, trivial⟩ cocone_maps X Y f g := ⟨Y, 𝟙 _, by apply ULift.ext apply Subsingleton.elim⟩ #align category_theory.is_filtered_or_empty_of_semilattice_sup CategoryTheory.isFilteredOrEmpty_of_semilatticeSup instance (priority := 100) isFiltered_of_semilatticeSup_nonempty (α : Type u) [SemilatticeSup α] [Nonempty α] : IsFiltered α where #align category_theory.is_filtered_of_semilattice_sup_nonempty CategoryTheory.isFiltered_of_semilatticeSup_nonempty instance (priority := 100) isFilteredOrEmpty_of_directed_le (α : Type u) [Preorder α] [IsDirected α (· ≤ ·)] : IsFilteredOrEmpty α where cocone_objs X Y := let ⟨Z, h1, h2⟩ := exists_ge_ge X Y ⟨Z, homOfLE h1, homOfLE h2, trivial⟩ cocone_maps X Y f g := ⟨Y, 𝟙 _, by apply ULift.ext apply Subsingleton.elim⟩ #align category_theory.is_filtered_or_empty_of_directed_le CategoryTheory.isFilteredOrEmpty_of_directed_le instance (priority := 100) isFiltered_of_directed_le_nonempty (α : Type u) [Preorder α] [IsDirected α (· ≤ ·)] [Nonempty α] : IsFiltered α where #align category_theory.is_filtered_of_directed_le_nonempty CategoryTheory.isFiltered_of_directed_le_nonempty -- Sanity checks example (α : Type u) [SemilatticeSup α] [OrderBot α] : IsFiltered α := by infer_instance example (α : Type u) [SemilatticeSup α] [OrderTop α] : IsFiltered α := by infer_instance instance : IsFiltered (Discrete PUnit) where cocone_objs X Y := ⟨⟨PUnit.unit⟩, ⟨⟨by trivial⟩⟩, ⟨⟨Subsingleton.elim _ _⟩⟩, trivial⟩ cocone_maps X Y f g := ⟨⟨PUnit.unit⟩, ⟨⟨by trivial⟩⟩, by apply ULift.ext apply Subsingleton.elim⟩ namespace IsFiltered namespace IsFiltered section OfCocone open CategoryTheory.Limits
Mathlib/CategoryTheory/Filtered/Basic.lean
372
388
theorem of_cocone_nonempty (h : ∀ {J : Type w} [SmallCategory J] [FinCategory J] (F : J ⥤ C), Nonempty (Cocone F)) : IsFiltered C := by
have : Nonempty C := by obtain ⟨c⟩ := h (Functor.empty _) exact ⟨c.pt⟩ have : IsFilteredOrEmpty C := by refine ⟨?_, ?_⟩ · intros X Y obtain ⟨c⟩ := h (ULiftHom.down ⋙ ULift.downFunctor ⋙ pair X Y) exact ⟨c.pt, c.ι.app ⟨⟨WalkingPair.left⟩⟩, c.ι.app ⟨⟨WalkingPair.right⟩⟩, trivial⟩ · intros X Y f g obtain ⟨c⟩ := h (ULiftHom.down ⋙ ULift.downFunctor ⋙ parallelPair f g) refine ⟨c.pt, c.ι.app ⟨WalkingParallelPair.one⟩, ?_⟩ have h₁ := c.ι.naturality ⟨WalkingParallelPairHom.left⟩ have h₂ := c.ι.naturality ⟨WalkingParallelPairHom.right⟩ simp_all apply IsFiltered.mk
415
import Mathlib.Topology.Category.TopCat.Limits.Basic import Mathlib.CategoryTheory.Filtered.Basic #align_import topology.category.Top.limits.cofiltered from "leanprover-community/mathlib"@"dbdf71cee7bb20367cb7e37279c08b0c218cf967" -- Porting note: every ML3 decl has an uppercase letter set_option linter.uppercaseLean3 false open TopologicalSpace open CategoryTheory open CategoryTheory.Limits universe u v w noncomputable section namespace TopCat section CofilteredLimit variable {J : Type v} [SmallCategory J] [IsCofiltered J] (F : J ⥤ TopCat.{max v u}) (C : Cone F) (hC : IsLimit C)
Mathlib/Topology/Category/TopCat/Limits/Cofiltered.lean
43
122
theorem isTopologicalBasis_cofiltered_limit (T : ∀ j, Set (Set (F.obj j))) (hT : ∀ j, IsTopologicalBasis (T j)) (univ : ∀ i : J, Set.univ ∈ T i) (inter : ∀ (i) (U1 U2 : Set (F.obj i)), U1 ∈ T i → U2 ∈ T i → U1 ∩ U2 ∈ T i) (compat : ∀ (i j : J) (f : i ⟶ j) (V : Set (F.obj j)) (_hV : V ∈ T j), F.map f ⁻¹' V ∈ T i) : IsTopologicalBasis {U : Set C.pt | ∃ (j : _) (V : Set (F.obj j)), V ∈ T j ∧ U = C.π.app j ⁻¹' V} := by
classical -- The limit cone for `F` whose topology is defined as an infimum. let D := limitConeInfi F -- The isomorphism between the cone point of `C` and the cone point of `D`. let E : C.pt ≅ D.pt := hC.conePointUniqueUpToIso (limitConeInfiIsLimit _) have hE : Inducing E.hom := (TopCat.homeoOfIso E).inducing -- Reduce to the assertion of the theorem with `D` instead of `C`. suffices IsTopologicalBasis {U : Set D.pt | ∃ (j : _) (V : Set (F.obj j)), V ∈ T j ∧ U = D.π.app j ⁻¹' V} by convert this.inducing hE ext U0 constructor · rintro ⟨j, V, hV, rfl⟩ exact ⟨D.π.app j ⁻¹' V, ⟨j, V, hV, rfl⟩, rfl⟩ · rintro ⟨W, ⟨j, V, hV, rfl⟩, rfl⟩ exact ⟨j, V, hV, rfl⟩ -- Using `D`, we can apply the characterization of the topological basis of a -- topology defined as an infimum... convert IsTopologicalBasis.iInf_induced hT fun j (x : D.pt) => D.π.app j x using 1 ext U0 constructor · rintro ⟨j, V, hV, rfl⟩ let U : ∀ i, Set (F.obj i) := fun i => if h : i = j then by rw [h]; exact V else Set.univ refine ⟨U, {j}, ?_, ?_⟩ · simp only [Finset.mem_singleton] rintro i rfl simpa [U] · simp [U] · rintro ⟨U, G, h1, h2⟩ obtain ⟨j, hj⟩ := IsCofiltered.inf_objs_exists G let g : ∀ e ∈ G, j ⟶ e := fun _ he => (hj he).some let Vs : J → Set (F.obj j) := fun e => if h : e ∈ G then F.map (g e h) ⁻¹' U e else Set.univ let V : Set (F.obj j) := ⋂ (e : J) (_he : e ∈ G), Vs e refine ⟨j, V, ?_, ?_⟩ · -- An intermediate claim used to apply induction along `G : Finset J` later on. have : ∀ (S : Set (Set (F.obj j))) (E : Finset J) (P : J → Set (F.obj j)) (_univ : Set.univ ∈ S) (_inter : ∀ A B : Set (F.obj j), A ∈ S → B ∈ S → A ∩ B ∈ S) (_cond : ∀ (e : J) (_he : e ∈ E), P e ∈ S), (⋂ (e) (_he : e ∈ E), P e) ∈ S := by intro S E induction E using Finset.induction_on with | empty => intro P he _hh simpa | @insert a E _ha hh1 => intro hh2 hh3 hh4 hh5 rw [Finset.set_biInter_insert] refine hh4 _ _ (hh5 _ (Finset.mem_insert_self _ _)) (hh1 _ hh3 hh4 ?_) intro e he exact hh5 e (Finset.mem_insert_of_mem he) -- use the intermediate claim to finish off the goal using `univ` and `inter`. refine this _ _ _ (univ _) (inter _) ?_ intro e he dsimp [Vs] rw [dif_pos he] exact compat j e (g e he) (U e) (h1 e he) · -- conclude... rw [h2] change _ = (D.π.app j)⁻¹' ⋂ (e : J) (_ : e ∈ G), Vs e rw [Set.preimage_iInter] apply congrArg ext1 e erw [Set.preimage_iInter] apply congrArg ext1 he -- Porting note: needed more hand holding here change (D.π.app e)⁻¹' U e = (D.π.app j) ⁻¹' if h : e ∈ G then F.map (g e h) ⁻¹' U e else Set.univ rw [dif_pos he, ← Set.preimage_comp] apply congrFun apply congrArg erw [← coe_comp, D.w] -- now `erw` after #13170 rfl
416
import Mathlib.AlgebraicTopology.DoldKan.EquivalenceAdditive import Mathlib.AlgebraicTopology.DoldKan.Compatibility import Mathlib.CategoryTheory.Idempotents.SimplicialObject #align_import algebraic_topology.dold_kan.equivalence_pseudoabelian from "leanprover-community/mathlib"@"32a7e535287f9c73f2e4d2aef306a39190f0b504" noncomputable section open CategoryTheory CategoryTheory.Category CategoryTheory.Limits CategoryTheory.Idempotents variable {C : Type*} [Category C] [Preadditive C] namespace CategoryTheory namespace Idempotents namespace DoldKan open AlgebraicTopology.DoldKan @[simps!, nolint unusedArguments] def N [IsIdempotentComplete C] [HasFiniteCoproducts C] : SimplicialObject C ⥤ ChainComplex C ℕ := N₁ ⋙ (toKaroubiEquivalence _).inverse set_option linter.uppercaseLean3 false in #align category_theory.idempotents.dold_kan.N CategoryTheory.Idempotents.DoldKan.N @[simps!, nolint unusedArguments] def Γ [IsIdempotentComplete C] [HasFiniteCoproducts C] : ChainComplex C ℕ ⥤ SimplicialObject C := Γ₀ #align category_theory.idempotents.dold_kan.Γ CategoryTheory.Idempotents.DoldKan.Γ variable [IsIdempotentComplete C] [HasFiniteCoproducts C] def isoN₁ : (toKaroubiEquivalence (SimplicialObject C)).functor ⋙ Preadditive.DoldKan.equivalence.functor ≅ N₁ := toKaroubiCompN₂IsoN₁ @[simp] lemma isoN₁_hom_app_f (X : SimplicialObject C) : (isoN₁.hom.app X).f = PInfty := rfl def isoΓ₀ : (toKaroubiEquivalence (ChainComplex C ℕ)).functor ⋙ Preadditive.DoldKan.equivalence.inverse ≅ Γ ⋙ (toKaroubiEquivalence _).functor := (functorExtension₂CompWhiskeringLeftToKaroubiIso _ _).app Γ₀ @[simp] lemma N₂_map_isoΓ₀_hom_app_f (X : ChainComplex C ℕ) : (N₂.map (isoΓ₀.hom.app X)).f = PInfty := by ext apply comp_id def equivalence : SimplicialObject C ≌ ChainComplex C ℕ := Compatibility.equivalence isoN₁ isoΓ₀ #align category_theory.idempotents.dold_kan.equivalence CategoryTheory.Idempotents.DoldKan.equivalence theorem equivalence_functor : (equivalence : SimplicialObject C ≌ _).functor = N := rfl #align category_theory.idempotents.dold_kan.equivalence_functor CategoryTheory.Idempotents.DoldKan.equivalence_functor theorem equivalence_inverse : (equivalence : SimplicialObject C ≌ _).inverse = Γ := rfl #align category_theory.idempotents.dold_kan.equivalence_inverse CategoryTheory.Idempotents.DoldKan.equivalence_inverse
Mathlib/AlgebraicTopology/DoldKan/EquivalencePseudoabelian.lean
108
114
theorem hη : Compatibility.τ₀ = Compatibility.τ₁ isoN₁ isoΓ₀ (N₁Γ₀ : Γ ⋙ N₁ ≅ (toKaroubiEquivalence (ChainComplex C ℕ)).functor) := by
ext K : 3 simp only [Compatibility.τ₀_hom_app, Compatibility.τ₁_hom_app] exact (N₂Γ₂_compatible_with_N₁Γ₀ K).trans (by simp )
417
import Mathlib.AlgebraicTopology.DoldKan.EquivalenceAdditive import Mathlib.AlgebraicTopology.DoldKan.Compatibility import Mathlib.CategoryTheory.Idempotents.SimplicialObject #align_import algebraic_topology.dold_kan.equivalence_pseudoabelian from "leanprover-community/mathlib"@"32a7e535287f9c73f2e4d2aef306a39190f0b504" noncomputable section open CategoryTheory CategoryTheory.Category CategoryTheory.Limits CategoryTheory.Idempotents variable {C : Type*} [Category C] [Preadditive C] namespace CategoryTheory namespace Idempotents namespace DoldKan open AlgebraicTopology.DoldKan @[simps!, nolint unusedArguments] def N [IsIdempotentComplete C] [HasFiniteCoproducts C] : SimplicialObject C ⥤ ChainComplex C ℕ := N₁ ⋙ (toKaroubiEquivalence _).inverse set_option linter.uppercaseLean3 false in #align category_theory.idempotents.dold_kan.N CategoryTheory.Idempotents.DoldKan.N @[simps!, nolint unusedArguments] def Γ [IsIdempotentComplete C] [HasFiniteCoproducts C] : ChainComplex C ℕ ⥤ SimplicialObject C := Γ₀ #align category_theory.idempotents.dold_kan.Γ CategoryTheory.Idempotents.DoldKan.Γ variable [IsIdempotentComplete C] [HasFiniteCoproducts C] def isoN₁ : (toKaroubiEquivalence (SimplicialObject C)).functor ⋙ Preadditive.DoldKan.equivalence.functor ≅ N₁ := toKaroubiCompN₂IsoN₁ @[simp] lemma isoN₁_hom_app_f (X : SimplicialObject C) : (isoN₁.hom.app X).f = PInfty := rfl def isoΓ₀ : (toKaroubiEquivalence (ChainComplex C ℕ)).functor ⋙ Preadditive.DoldKan.equivalence.inverse ≅ Γ ⋙ (toKaroubiEquivalence _).functor := (functorExtension₂CompWhiskeringLeftToKaroubiIso _ _).app Γ₀ @[simp] lemma N₂_map_isoΓ₀_hom_app_f (X : ChainComplex C ℕ) : (N₂.map (isoΓ₀.hom.app X)).f = PInfty := by ext apply comp_id def equivalence : SimplicialObject C ≌ ChainComplex C ℕ := Compatibility.equivalence isoN₁ isoΓ₀ #align category_theory.idempotents.dold_kan.equivalence CategoryTheory.Idempotents.DoldKan.equivalence theorem equivalence_functor : (equivalence : SimplicialObject C ≌ _).functor = N := rfl #align category_theory.idempotents.dold_kan.equivalence_functor CategoryTheory.Idempotents.DoldKan.equivalence_functor theorem equivalence_inverse : (equivalence : SimplicialObject C ≌ _).inverse = Γ := rfl #align category_theory.idempotents.dold_kan.equivalence_inverse CategoryTheory.Idempotents.DoldKan.equivalence_inverse theorem hη : Compatibility.τ₀ = Compatibility.τ₁ isoN₁ isoΓ₀ (N₁Γ₀ : Γ ⋙ N₁ ≅ (toKaroubiEquivalence (ChainComplex C ℕ)).functor) := by ext K : 3 simp only [Compatibility.τ₀_hom_app, Compatibility.τ₁_hom_app] exact (N₂Γ₂_compatible_with_N₁Γ₀ K).trans (by simp ) #align category_theory.idempotents.dold_kan.hη CategoryTheory.Idempotents.DoldKan.hη @[simps!] def η : Γ ⋙ N ≅ 𝟭 (ChainComplex C ℕ) := Compatibility.equivalenceCounitIso (N₁Γ₀ : (Γ : ChainComplex C ℕ ⥤ _) ⋙ N₁ ≅ (toKaroubiEquivalence _).functor) #align category_theory.idempotents.dold_kan.η CategoryTheory.Idempotents.DoldKan.η theorem equivalence_counitIso : DoldKan.equivalence.counitIso = (η : Γ ⋙ N ≅ 𝟭 (ChainComplex C ℕ)) := Compatibility.equivalenceCounitIso_eq hη #align category_theory.idempotents.dold_kan.equivalence_counit_iso CategoryTheory.Idempotents.DoldKan.equivalence_counitIso
Mathlib/AlgebraicTopology/DoldKan/EquivalencePseudoabelian.lean
129
144
theorem hε : Compatibility.υ (isoN₁) = (Γ₂N₁ : (toKaroubiEquivalence _).functor ≅ (N₁ : SimplicialObject C ⥤ _) ⋙ Preadditive.DoldKan.equivalence.inverse) := by
dsimp only [isoN₁] ext1 rw [← cancel_epi Γ₂N₁.inv, Iso.inv_hom_id] ext X : 2 rw [NatTrans.comp_app] erw [compatibility_Γ₂N₁_Γ₂N₂_natTrans X] rw [Compatibility.υ_hom_app, Preadditive.DoldKan.equivalence_unitIso, Iso.app_inv, assoc] erw [← NatTrans.comp_app_assoc, IsIso.hom_inv_id] rw [NatTrans.id_app, id_comp, NatTrans.id_app, Γ₂N₂ToKaroubiIso_inv_app] dsimp only [Preadditive.DoldKan.equivalence_inverse, Preadditive.DoldKan.Γ] rw [← Γ₂.map_comp, Iso.inv_hom_id_app, Γ₂.map_id] rfl
417
import Mathlib.Data.Opposite import Mathlib.Tactic.Cases #align_import combinatorics.quiver.basic from "leanprover-community/mathlib"@"56adee5b5eef9e734d82272918300fca4f3e7cef" open Opposite -- We use the same universe order as in category theory. -- See note [CategoryTheory universes] universe v v₁ v₂ u u₁ u₂ class Quiver (V : Type u) where Hom : V → V → Sort v #align quiver Quiver #align quiver.hom Quiver.Hom infixr:10 " ⟶ " => Quiver.Hom structure Prefunctor (V : Type u₁) [Quiver.{v₁} V] (W : Type u₂) [Quiver.{v₂} W] where obj : V → W map : ∀ {X Y : V}, (X ⟶ Y) → (obj X ⟶ obj Y) #align prefunctor Prefunctor namespace Prefunctor -- Porting note: added during port. -- These lemmas can not be `@[simp]` because after `whnfR` they have a variable on the LHS. -- Nevertheless they are sometimes useful when building functors. lemma mk_obj {V W : Type*} [Quiver V] [Quiver W] {obj : V → W} {map} {X : V} : (Prefunctor.mk obj map).obj X = obj X := rfl lemma mk_map {V W : Type*} [Quiver V] [Quiver W] {obj : V → W} {map} {X Y : V} {f : X ⟶ Y} : (Prefunctor.mk obj map).map f = map f := rfl @[ext]
Mathlib/Combinatorics/Quiver/Basic.lean
76
87
theorem ext {V : Type u} [Quiver.{v₁} V] {W : Type u₂} [Quiver.{v₂} W] {F G : Prefunctor V W} (h_obj : ∀ X, F.obj X = G.obj X) (h_map : ∀ (X Y : V) (f : X ⟶ Y), F.map f = Eq.recOn (h_obj Y).symm (Eq.recOn (h_obj X).symm (G.map f))) : F = G := by
cases' F with F_obj _ cases' G with G_obj _ obtain rfl : F_obj = G_obj := by ext X apply h_obj congr funext X Y f simpa using h_map X Y f
418
import Mathlib.Data.Opposite import Mathlib.Tactic.Cases #align_import combinatorics.quiver.basic from "leanprover-community/mathlib"@"56adee5b5eef9e734d82272918300fca4f3e7cef" open Opposite -- We use the same universe order as in category theory. -- See note [CategoryTheory universes] universe v v₁ v₂ u u₁ u₂ class Quiver (V : Type u) where Hom : V → V → Sort v #align quiver Quiver #align quiver.hom Quiver.Hom infixr:10 " ⟶ " => Quiver.Hom structure Prefunctor (V : Type u₁) [Quiver.{v₁} V] (W : Type u₂) [Quiver.{v₂} W] where obj : V → W map : ∀ {X Y : V}, (X ⟶ Y) → (obj X ⟶ obj Y) #align prefunctor Prefunctor namespace Prefunctor -- Porting note: added during port. -- These lemmas can not be `@[simp]` because after `whnfR` they have a variable on the LHS. -- Nevertheless they are sometimes useful when building functors. lemma mk_obj {V W : Type*} [Quiver V] [Quiver W] {obj : V → W} {map} {X : V} : (Prefunctor.mk obj map).obj X = obj X := rfl lemma mk_map {V W : Type*} [Quiver V] [Quiver W] {obj : V → W} {map} {X Y : V} {f : X ⟶ Y} : (Prefunctor.mk obj map).map f = map f := rfl @[ext] theorem ext {V : Type u} [Quiver.{v₁} V] {W : Type u₂} [Quiver.{v₂} W] {F G : Prefunctor V W} (h_obj : ∀ X, F.obj X = G.obj X) (h_map : ∀ (X Y : V) (f : X ⟶ Y), F.map f = Eq.recOn (h_obj Y).symm (Eq.recOn (h_obj X).symm (G.map f))) : F = G := by cases' F with F_obj _ cases' G with G_obj _ obtain rfl : F_obj = G_obj := by ext X apply h_obj congr funext X Y f simpa using h_map X Y f #align prefunctor.ext Prefunctor.ext @[simps] def id (V : Type*) [Quiver V] : Prefunctor V V where obj := fun X => X map f := f #align prefunctor.id Prefunctor.id #align prefunctor.id_obj Prefunctor.id_obj #align prefunctor.id_map Prefunctor.id_map instance (V : Type*) [Quiver V] : Inhabited (Prefunctor V V) := ⟨id V⟩ @[simps] def comp {U : Type*} [Quiver U] {V : Type*} [Quiver V] {W : Type*} [Quiver W] (F : Prefunctor U V) (G : Prefunctor V W) : Prefunctor U W where obj X := G.obj (F.obj X) map f := G.map (F.map f) #align prefunctor.comp Prefunctor.comp #align prefunctor.comp_obj Prefunctor.comp_obj #align prefunctor.comp_map Prefunctor.comp_map @[simp] theorem comp_id {U V : Type*} [Quiver U] [Quiver V] (F : Prefunctor U V) : F.comp (id _) = F := rfl #align prefunctor.comp_id Prefunctor.comp_id @[simp] theorem id_comp {U V : Type*} [Quiver U] [Quiver V] (F : Prefunctor U V) : (id _).comp F = F := rfl #align prefunctor.id_comp Prefunctor.id_comp @[simp] theorem comp_assoc {U V W Z : Type*} [Quiver U] [Quiver V] [Quiver W] [Quiver Z] (F : Prefunctor U V) (G : Prefunctor V W) (H : Prefunctor W Z) : (F.comp G).comp H = F.comp (G.comp H) := rfl #align prefunctor.comp_assoc Prefunctor.comp_assoc infixl:50 " ⥤q " => Prefunctor infixl:60 " ⋙q " => Prefunctor.comp notation "𝟭q" => id
Mathlib/Combinatorics/Quiver/Basic.lean
138
140
theorem congr_map {U V : Type*} [Quiver U] [Quiver V] (F : U ⥤q V) {X Y : U} {f g : X ⟶ Y} (h : f = g) : F.map f = F.map g := by
rw [h]
418
import Mathlib.Combinatorics.Quiver.Basic #align_import combinatorics.quiver.push from "leanprover-community/mathlib"@"2258b40dacd2942571c8ce136215350c702dc78f" namespace Quiver universe v v₁ v₂ u u₁ u₂ variable {V : Type*} [Quiver V] {W : Type*} (σ : V → W) @[nolint unusedArguments] def Push (_ : V → W) := W #align quiver.push Quiver.Push instance [h : Nonempty W] : Nonempty (Push σ) := h inductive PushQuiver {V : Type u} [Quiver.{v} V] {W : Type u₂} (σ : V → W) : W → W → Type max u u₂ v | arrow {X Y : V} (f : X ⟶ Y) : PushQuiver σ (σ X) (σ Y) #align quiver.push_quiver Quiver.PushQuiver instance : Quiver (Push σ) := ⟨PushQuiver σ⟩ namespace Push def of : V ⥤q Push σ where obj := σ map f := PushQuiver.arrow f #align quiver.push.of Quiver.Push.of @[simp] theorem of_obj : (of σ).obj = σ := rfl #align quiver.push.of_obj Quiver.Push.of_obj variable {W' : Type*} [Quiver W'] (φ : V ⥤q W') (τ : W → W') (h : ∀ x, φ.obj x = τ (σ x)) noncomputable def lift : Push σ ⥤q W' where obj := τ map := @PushQuiver.rec V _ W σ (fun X Y _ => τ X ⟶ τ Y) @fun X Y f => by dsimp only rw [← h X, ← h Y] exact φ.map f #align quiver.push.lift Quiver.Push.lift theorem lift_obj : (lift σ φ τ h).obj = τ := rfl #align quiver.push.lift_obj Quiver.Push.lift_obj
Mathlib/Combinatorics/Quiver/Push.lean
73
89
theorem lift_comp : (of σ ⋙q lift σ φ τ h) = φ := by
fapply Prefunctor.ext · rintro X simp only [Prefunctor.comp_obj] apply Eq.symm exact h X · rintro X Y f simp only [Prefunctor.comp_map] apply eq_of_heq iterate 2 apply (cast_heq _ _).trans apply HEq.symm apply (eqRec_heq _ _).trans have : ∀ {α γ} {β : α → γ → Sort _} {a a'} (p : a = a') g (b : β a g), HEq (p ▸ b) b := by intros subst_vars rfl apply this
419
import Mathlib.Combinatorics.Quiver.Basic #align_import combinatorics.quiver.push from "leanprover-community/mathlib"@"2258b40dacd2942571c8ce136215350c702dc78f" namespace Quiver universe v v₁ v₂ u u₁ u₂ variable {V : Type*} [Quiver V] {W : Type*} (σ : V → W) @[nolint unusedArguments] def Push (_ : V → W) := W #align quiver.push Quiver.Push instance [h : Nonempty W] : Nonempty (Push σ) := h inductive PushQuiver {V : Type u} [Quiver.{v} V] {W : Type u₂} (σ : V → W) : W → W → Type max u u₂ v | arrow {X Y : V} (f : X ⟶ Y) : PushQuiver σ (σ X) (σ Y) #align quiver.push_quiver Quiver.PushQuiver instance : Quiver (Push σ) := ⟨PushQuiver σ⟩ namespace Push def of : V ⥤q Push σ where obj := σ map f := PushQuiver.arrow f #align quiver.push.of Quiver.Push.of @[simp] theorem of_obj : (of σ).obj = σ := rfl #align quiver.push.of_obj Quiver.Push.of_obj variable {W' : Type*} [Quiver W'] (φ : V ⥤q W') (τ : W → W') (h : ∀ x, φ.obj x = τ (σ x)) noncomputable def lift : Push σ ⥤q W' where obj := τ map := @PushQuiver.rec V _ W σ (fun X Y _ => τ X ⟶ τ Y) @fun X Y f => by dsimp only rw [← h X, ← h Y] exact φ.map f #align quiver.push.lift Quiver.Push.lift theorem lift_obj : (lift σ φ τ h).obj = τ := rfl #align quiver.push.lift_obj Quiver.Push.lift_obj theorem lift_comp : (of σ ⋙q lift σ φ τ h) = φ := by fapply Prefunctor.ext · rintro X simp only [Prefunctor.comp_obj] apply Eq.symm exact h X · rintro X Y f simp only [Prefunctor.comp_map] apply eq_of_heq iterate 2 apply (cast_heq _ _).trans apply HEq.symm apply (eqRec_heq _ _).trans have : ∀ {α γ} {β : α → γ → Sort _} {a a'} (p : a = a') g (b : β a g), HEq (p ▸ b) b := by intros subst_vars rfl apply this #align quiver.push.lift_comp Quiver.Push.lift_comp
Mathlib/Combinatorics/Quiver/Push.lean
92
102
theorem lift_unique (Φ : Push σ ⥤q W') (Φ₀ : Φ.obj = τ) (Φcomp : (of σ ⋙q Φ) = φ) : Φ = lift σ φ τ h := by
dsimp only [of, lift] fapply Prefunctor.ext · intro X simp only rw [Φ₀] · rintro _ _ ⟨⟩ subst_vars simp only [Prefunctor.comp_map, cast_eq] rfl
419
import Mathlib.Algebra.Module.Defs import Mathlib.Data.Fintype.BigOperators import Mathlib.GroupTheory.GroupAction.BigOperators #align_import algebra.module.big_operators from "leanprover-community/mathlib"@"509de852e1de55e1efa8eacfa11df0823f26f226" variable {ι κ α β R M : Type*} section AddCommMonoid variable [Semiring R] [AddCommMonoid M] [Module R M] (r s : R) (x y : M) theorem List.sum_smul {l : List R} {x : M} : l.sum • x = (l.map fun r ↦ r • x).sum := map_list_sum ((smulAddHom R M).flip x) l #align list.sum_smul List.sum_smul theorem Multiset.sum_smul {l : Multiset R} {x : M} : l.sum • x = (l.map fun r ↦ r • x).sum := ((smulAddHom R M).flip x).map_multiset_sum l #align multiset.sum_smul Multiset.sum_smul
Mathlib/Algebra/Module/BigOperators.lean
30
34
theorem Multiset.sum_smul_sum {s : Multiset R} {t : Multiset M} : s.sum • t.sum = ((s ×ˢ t).map fun p : R × M ↦ p.fst • p.snd).sum := by
induction' s using Multiset.induction with a s ih · simp · simp [add_smul, ih, ← Multiset.smul_sum]
420
import Mathlib.Algebra.Module.Defs import Mathlib.Data.Fintype.BigOperators import Mathlib.GroupTheory.GroupAction.BigOperators #align_import algebra.module.big_operators from "leanprover-community/mathlib"@"509de852e1de55e1efa8eacfa11df0823f26f226" variable {ι κ α β R M : Type*} section AddCommMonoid variable [Semiring R] [AddCommMonoid M] [Module R M] (r s : R) (x y : M) theorem List.sum_smul {l : List R} {x : M} : l.sum • x = (l.map fun r ↦ r • x).sum := map_list_sum ((smulAddHom R M).flip x) l #align list.sum_smul List.sum_smul theorem Multiset.sum_smul {l : Multiset R} {x : M} : l.sum • x = (l.map fun r ↦ r • x).sum := ((smulAddHom R M).flip x).map_multiset_sum l #align multiset.sum_smul Multiset.sum_smul theorem Multiset.sum_smul_sum {s : Multiset R} {t : Multiset M} : s.sum • t.sum = ((s ×ˢ t).map fun p : R × M ↦ p.fst • p.snd).sum := by induction' s using Multiset.induction with a s ih · simp · simp [add_smul, ih, ← Multiset.smul_sum] #align multiset.sum_smul_sum Multiset.sum_smul_sum theorem Finset.sum_smul {f : ι → R} {s : Finset ι} {x : M} : (∑ i ∈ s, f i) • x = ∑ i ∈ s, f i • x := map_sum ((smulAddHom R M).flip x) f s #align finset.sum_smul Finset.sum_smul
Mathlib/Algebra/Module/BigOperators.lean
41
45
theorem Finset.sum_smul_sum {f : α → R} {g : β → M} {s : Finset α} {t : Finset β} : ((∑ i ∈ s, f i) • ∑ i ∈ t, g i) = ∑ p ∈ s ×ˢ t, f p.fst • g p.snd := by
rw [Finset.sum_product, Finset.sum_smul, Finset.sum_congr rfl] intros rw [Finset.smul_sum]
420
import Mathlib.Algebra.Module.Defs import Mathlib.Data.Fintype.BigOperators import Mathlib.GroupTheory.GroupAction.BigOperators #align_import algebra.module.big_operators from "leanprover-community/mathlib"@"509de852e1de55e1efa8eacfa11df0823f26f226" variable {ι κ α β R M : Type*}
Mathlib/Algebra/Module/BigOperators.lean
50
51
theorem Finset.cast_card [CommSemiring R] (s : Finset α) : (s.card : R) = ∑ a ∈ s, 1 := by
rw [Finset.sum_const, Nat.smul_one_eq_cast]
420
import Mathlib.CategoryTheory.Adjunction.Basic import Mathlib.CategoryTheory.Category.Preorder import Mathlib.CategoryTheory.IsomorphismClasses import Mathlib.CategoryTheory.Thin #align_import category_theory.skeletal from "leanprover-community/mathlib"@"28aa996fc6fb4317f0083c4e6daf79878d81be33" universe v₁ v₂ v₃ u₁ u₂ u₃ namespace CategoryTheory open Category variable (C : Type u₁) [Category.{v₁} C] variable (D : Type u₂) [Category.{v₂} D] variable {E : Type u₃} [Category.{v₃} E] def Skeletal : Prop := ∀ ⦃X Y : C⦄, IsIsomorphic X Y → X = Y #align category_theory.skeletal CategoryTheory.Skeletal structure IsSkeletonOf (F : D ⥤ C) : Prop where skel : Skeletal D eqv : F.IsEquivalence := by infer_instance #align category_theory.is_skeleton_of CategoryTheory.IsSkeletonOf attribute [local instance] isIsomorphicSetoid variable {C D} theorem Functor.eq_of_iso {F₁ F₂ : D ⥤ C} [Quiver.IsThin C] (hC : Skeletal C) (hF : F₁ ≅ F₂) : F₁ = F₂ := Functor.ext (fun X => hC ⟨hF.app X⟩) fun _ _ _ => Subsingleton.elim _ _ #align category_theory.functor.eq_of_iso CategoryTheory.Functor.eq_of_iso theorem functor_skeletal [Quiver.IsThin C] (hC : Skeletal C) : Skeletal (D ⥤ C) := fun _ _ h => h.elim (Functor.eq_of_iso hC) #align category_theory.functor_skeletal CategoryTheory.functor_skeletal variable (C D) def Skeleton : Type u₁ := InducedCategory C Quotient.out #align category_theory.skeleton CategoryTheory.Skeleton instance [Inhabited C] : Inhabited (Skeleton C) := ⟨⟦default⟧⟩ -- Porting note: previously `Skeleton` used `deriving Category` noncomputable instance : Category (Skeleton C) := by apply InducedCategory.category @[simps!] noncomputable def fromSkeleton : Skeleton C ⥤ C := inducedFunctor _ #align category_theory.from_skeleton CategoryTheory.fromSkeleton -- Porting note: previously `fromSkeleton` used `deriving Faithful, Full` noncomputable instance : (fromSkeleton C).Full := by apply InducedCategory.full noncomputable instance : (fromSkeleton C).Faithful := by apply InducedCategory.faithful instance : (fromSkeleton C).EssSurj where mem_essImage X := ⟨Quotient.mk' X, Quotient.mk_out X⟩ -- Porting note: named this instance noncomputable instance fromSkeleton.isEquivalence : (fromSkeleton C).IsEquivalence where noncomputable def skeletonEquivalence : Skeleton C ≌ C := (fromSkeleton C).asEquivalence #align category_theory.skeleton_equivalence CategoryTheory.skeletonEquivalence
Mathlib/CategoryTheory/Skeletal.lean
108
111
theorem skeleton_skeletal : Skeletal (Skeleton C) := by
rintro X Y ⟨h⟩ have : X.out ≈ Y.out := ⟨(fromSkeleton C).mapIso h⟩ simpa using Quotient.sound this
421
import Mathlib.Algebra.Homology.Exact import Mathlib.CategoryTheory.Limits.Shapes.Biproducts import Mathlib.CategoryTheory.Adjunction.Limits import Mathlib.CategoryTheory.Limits.Preserves.Finite #align_import category_theory.preadditive.projective from "leanprover-community/mathlib"@"3974a774a707e2e06046a14c0eaef4654584fada" noncomputable section open CategoryTheory Limits Opposite universe v u v' u' namespace CategoryTheory variable {C : Type u} [Category.{v} C] class Projective (P : C) : Prop where factors : ∀ {E X : C} (f : P ⟶ X) (e : E ⟶ X) [Epi e], ∃ f', f' ≫ e = f #align category_theory.projective CategoryTheory.Projective lemma Limits.IsZero.projective {X : C} (h : IsZero X) : Projective X where factors _ _ _ := ⟨h.to_ _, h.eq_of_src _ _⟩ section -- Porting note(#5171): was @[nolint has_nonempty_instance] structure ProjectivePresentation (X : C) where p : C [projective : Projective p] f : p ⟶ X [epi : Epi f] #align category_theory.projective_presentation CategoryTheory.ProjectivePresentation attribute [instance] ProjectivePresentation.projective ProjectivePresentation.epi variable (C) class EnoughProjectives : Prop where presentation : ∀ X : C, Nonempty (ProjectivePresentation X) #align category_theory.enough_projectives CategoryTheory.EnoughProjectives end namespace Projective def factorThru {P X E : C} [Projective P] (f : P ⟶ X) (e : E ⟶ X) [Epi e] : P ⟶ E := (Projective.factors f e).choose #align category_theory.projective.factor_thru CategoryTheory.Projective.factorThru @[reassoc (attr := simp)] theorem factorThru_comp {P X E : C} [Projective P] (f : P ⟶ X) (e : E ⟶ X) [Epi e] : factorThru f e ≫ e = f := (Projective.factors f e).choose_spec #align category_theory.projective.factor_thru_comp CategoryTheory.Projective.factorThru_comp section open ZeroObject instance zero_projective [HasZeroObject C] : Projective (0 : C) := (isZero_zero C).projective #align category_theory.projective.zero_projective CategoryTheory.Projective.zero_projective end theorem of_iso {P Q : C} (i : P ≅ Q) (hP : Projective P) : Projective Q where factors f e e_epi := let ⟨f', hf'⟩ := Projective.factors (i.hom ≫ f) e ⟨i.inv ≫ f', by simp [hf']⟩ #align category_theory.projective.of_iso CategoryTheory.Projective.of_iso theorem iso_iff {P Q : C} (i : P ≅ Q) : Projective P ↔ Projective Q := ⟨of_iso i, of_iso i.symm⟩ #align category_theory.projective.iso_iff CategoryTheory.Projective.iso_iff instance (X : Type u) : Projective X where factors f e _ := have he : Function.Surjective e := surjective_of_epi e ⟨fun x => (he (f x)).choose, funext fun x ↦ (he (f x)).choose_spec⟩ instance Type.enoughProjectives : EnoughProjectives (Type u) where presentation X := ⟨⟨X, 𝟙 X⟩⟩ #align category_theory.projective.Type.enough_projectives CategoryTheory.Projective.Type.enoughProjectives instance {P Q : C} [HasBinaryCoproduct P Q] [Projective P] [Projective Q] : Projective (P ⨿ Q) where factors f e epi := ⟨coprod.desc (factorThru (coprod.inl ≫ f) e) (factorThru (coprod.inr ≫ f) e), by aesop_cat⟩ instance {β : Type v} (g : β → C) [HasCoproduct g] [∀ b, Projective (g b)] : Projective (∐ g) where factors f e epi := ⟨Sigma.desc fun b => factorThru (Sigma.ι g b ≫ f) e, by aesop_cat⟩ instance {P Q : C} [HasZeroMorphisms C] [HasBinaryBiproduct P Q] [Projective P] [Projective Q] : Projective (P ⊞ Q) where factors f e epi := ⟨biprod.desc (factorThru (biprod.inl ≫ f) e) (factorThru (biprod.inr ≫ f) e), by aesop_cat⟩ instance {β : Type v} (g : β → C) [HasZeroMorphisms C] [HasBiproduct g] [∀ b, Projective (g b)] : Projective (⨁ g) where factors f e epi := ⟨biproduct.desc fun b => factorThru (biproduct.ι g b ≫ f) e, by aesop_cat⟩ theorem projective_iff_preservesEpimorphisms_coyoneda_obj (P : C) : Projective P ↔ (coyoneda.obj (op P)).PreservesEpimorphisms := ⟨fun hP => ⟨fun f _ => (epi_iff_surjective _).2 fun g => have : Projective (unop (op P)) := hP ⟨factorThru g f, factorThru_comp _ _⟩⟩, fun _ => ⟨fun f e _ => (epi_iff_surjective _).1 (inferInstance : Epi ((coyoneda.obj (op P)).map e)) f⟩⟩ #align category_theory.projective.projective_iff_preserves_epimorphisms_coyoneda_obj CategoryTheory.Projective.projective_iff_preservesEpimorphisms_coyoneda_obj namespace Adjunction variable {D : Type u'} [Category.{v'} D] {F : C ⥤ D} {G : D ⥤ C}
Mathlib/CategoryTheory/Preadditive/Projective.lean
208
214
theorem map_projective (adj : F ⊣ G) [G.PreservesEpimorphisms] (P : C) (hP : Projective P) : Projective (F.obj P) where factors f g _ := by
rcases hP.factors (adj.unit.app P ≫ G.map f) (G.map g) with ⟨f', hf'⟩ use F.map f' ≫ adj.counit.app _ rw [Category.assoc, ← Adjunction.counit_naturality, ← Category.assoc, ← F.map_comp, hf'] simp
422
import Mathlib.Algebra.Associated import Mathlib.Algebra.Ring.Int #align_import data.int.associated from "leanprover-community/mathlib"@"207cfac9fcd06138865b5d04f7091e46d9320432"
Mathlib/Data/Int/Associated.lean
21
30
theorem Int.natAbs_eq_iff_associated {a b : ℤ} : a.natAbs = b.natAbs ↔ Associated a b := by
refine Int.natAbs_eq_natAbs_iff.trans ?_ constructor · rintro (rfl | rfl) · rfl · exact ⟨-1, by simp⟩ · rintro ⟨u, rfl⟩ obtain rfl | rfl := Int.units_eq_one_or u · exact Or.inl (by simp) · exact Or.inr (by simp)
423
import Batteries.Data.RBMap.Basic import Batteries.Tactic.SeqFocus namespace Batteries namespace RBNode open RBColor attribute [simp] All theorem All.trivial (H : ∀ {x : α}, p x) : ∀ {t : RBNode α}, t.All p | nil => _root_.trivial | node .. => ⟨H, All.trivial H, All.trivial H⟩
.lake/packages/batteries/Batteries/Data/RBMap/WF.lean
27
28
theorem All_and {t : RBNode α} : t.All (fun a => p a ∧ q a) ↔ t.All p ∧ t.All q := by
induction t <;> simp [*, and_assoc, and_left_comm]
424
import Batteries.Data.RBMap.Basic import Batteries.Tactic.SeqFocus namespace Batteries namespace RBNode open RBColor attribute [simp] All theorem All.trivial (H : ∀ {x : α}, p x) : ∀ {t : RBNode α}, t.All p | nil => _root_.trivial | node .. => ⟨H, All.trivial H, All.trivial H⟩ theorem All_and {t : RBNode α} : t.All (fun a => p a ∧ q a) ↔ t.All p ∧ t.All q := by induction t <;> simp [*, and_assoc, and_left_comm] protected theorem cmpLT.flip (h₁ : cmpLT cmp x y) : cmpLT (flip cmp) y x := ⟨have : TransCmp cmp := inferInstanceAs (TransCmp (flip (flip cmp))); h₁.1⟩ theorem cmpLT.trans (h₁ : cmpLT cmp x y) (h₂ : cmpLT cmp y z) : cmpLT cmp x z := ⟨TransCmp.lt_trans h₁.1 h₂.1⟩ theorem cmpLT.trans_l {cmp x y} (H : cmpLT cmp x y) {t : RBNode α} (h : t.All (cmpLT cmp y ·)) : t.All (cmpLT cmp x ·) := h.imp fun h => H.trans h theorem cmpLT.trans_r {cmp x y} (H : cmpLT cmp x y) {a : RBNode α} (h : a.All (cmpLT cmp · x)) : a.All (cmpLT cmp · y) := h.imp fun h => h.trans H theorem cmpEq.lt_congr_left (H : cmpEq cmp x y) : cmpLT cmp x z ↔ cmpLT cmp y z := ⟨fun ⟨h⟩ => ⟨TransCmp.cmp_congr_left H.1 ▸ h⟩, fun ⟨h⟩ => ⟨TransCmp.cmp_congr_left H.1 ▸ h⟩⟩ theorem cmpEq.lt_congr_right (H : cmpEq cmp y z) : cmpLT cmp x y ↔ cmpLT cmp x z := ⟨fun ⟨h⟩ => ⟨TransCmp.cmp_congr_right H.1 ▸ h⟩, fun ⟨h⟩ => ⟨TransCmp.cmp_congr_right H.1 ▸ h⟩⟩ @[simp] theorem reverse_reverse (t : RBNode α) : t.reverse.reverse = t := by induction t <;> simp [*]
.lake/packages/batteries/Batteries/Data/RBMap/WF.lean
51
52
theorem reverse_eq_iff {t t' : RBNode α} : t.reverse = t' ↔ t = t'.reverse := by
constructor <;> rintro rfl <;> simp
424
import Mathlib.Topology.CompactOpen import Mathlib.Topology.Sets.Closeds open Function Set Filter TopologicalSpace open scoped Topology variable {X Y : Type*} [TopologicalSpace X] [TopologicalSpace Y] [CompactSpace Y]
Mathlib/Topology/ClopenBox.lean
36
44
theorem TopologicalSpace.Clopens.exists_prod_subset (W : Clopens (X × Y)) {a : X × Y} (h : a ∈ W) : ∃ U : Clopens X, a.1 ∈ U ∧ ∃ V : Clopens Y, a.2 ∈ V ∧ U ×ˢ V ≤ W := by
have hp : Continuous (fun y : Y ↦ (a.1, y)) := Continuous.Prod.mk _ let V : Set Y := {y | (a.1, y) ∈ W} have hV : IsCompact V := (W.2.1.preimage hp).isCompact let U : Set X := {x | MapsTo (Prod.mk x) V W} have hUV : U ×ˢ V ⊆ W := fun ⟨_, _⟩ hw ↦ hw.1 hw.2 exact ⟨⟨U, (ContinuousMap.isClopen_setOf_mapsTo hV W.2).preimage (ContinuousMap.id (X × Y)).curry.2⟩, by simp [U, V, MapsTo], ⟨V, W.2.preimage hp⟩, h, hUV⟩
425
import Mathlib.Topology.CompactOpen import Mathlib.Topology.Sets.Closeds open Function Set Filter TopologicalSpace open scoped Topology variable {X Y : Type*} [TopologicalSpace X] [TopologicalSpace Y] [CompactSpace Y] theorem TopologicalSpace.Clopens.exists_prod_subset (W : Clopens (X × Y)) {a : X × Y} (h : a ∈ W) : ∃ U : Clopens X, a.1 ∈ U ∧ ∃ V : Clopens Y, a.2 ∈ V ∧ U ×ˢ V ≤ W := by have hp : Continuous (fun y : Y ↦ (a.1, y)) := Continuous.Prod.mk _ let V : Set Y := {y | (a.1, y) ∈ W} have hV : IsCompact V := (W.2.1.preimage hp).isCompact let U : Set X := {x | MapsTo (Prod.mk x) V W} have hUV : U ×ˢ V ⊆ W := fun ⟨_, _⟩ hw ↦ hw.1 hw.2 exact ⟨⟨U, (ContinuousMap.isClopen_setOf_mapsTo hV W.2).preimage (ContinuousMap.id (X × Y)).curry.2⟩, by simp [U, V, MapsTo], ⟨V, W.2.preimage hp⟩, h, hUV⟩ variable [CompactSpace X]
Mathlib/Topology/ClopenBox.lean
50
61
theorem TopologicalSpace.Clopens.exists_finset_eq_sup_prod (W : Clopens (X × Y)) : ∃ (I : Finset (Clopens X × Clopens Y)), W = I.sup fun i ↦ i.1 ×ˢ i.2 := by
choose! U hxU V hxV hUV using fun x ↦ W.exists_prod_subset (a := x) rcases W.2.1.isCompact.elim_nhds_subcover (fun x ↦ U x ×ˢ V x) (fun x hx ↦ (U x ×ˢ V x).2.isOpen.mem_nhds ⟨hxU x hx, hxV x hx⟩) with ⟨I, hIW, hWI⟩ classical use I.image fun x ↦ (U x, V x) rw [Finset.sup_image] refine le_antisymm (fun x hx ↦ ?_) (Finset.sup_le fun x hx ↦ ?_) · rcases Set.mem_iUnion₂.1 (hWI hx) with ⟨i, hi, hxi⟩ exact SetLike.le_def.1 (Finset.le_sup hi) hxi · exact hUV _ <| hIW _ hx
425
import Mathlib.Algebra.Divisibility.Basic import Mathlib.Algebra.Group.Prod import Mathlib.Tactic.Common variable {ι G₁ G₂ : Type*} {G : ι → Type*} [Semigroup G₁] [Semigroup G₂] [∀ i, Semigroup (G i)]
Mathlib/Algebra/Divisibility/Prod.lean
16
20
theorem prod_dvd_iff {x y : G₁ × G₂} : x ∣ y ↔ x.1 ∣ y.1 ∧ x.2 ∣ y.2 := by
cases x; cases y simp only [dvd_def, Prod.exists, Prod.mk_mul_mk, Prod.mk.injEq, exists_and_left, exists_and_right, and_self, true_and]
426
import Mathlib.Algebra.Divisibility.Basic import Mathlib.Algebra.Group.Prod import Mathlib.Tactic.Common variable {ι G₁ G₂ : Type*} {G : ι → Type*} [Semigroup G₁] [Semigroup G₂] [∀ i, Semigroup (G i)] theorem prod_dvd_iff {x y : G₁ × G₂} : x ∣ y ↔ x.1 ∣ y.1 ∧ x.2 ∣ y.2 := by cases x; cases y simp only [dvd_def, Prod.exists, Prod.mk_mul_mk, Prod.mk.injEq, exists_and_left, exists_and_right, and_self, true_and] @[simp] theorem Prod.mk_dvd_mk {x₁ y₁ : G₁} {x₂ y₂ : G₂} : (x₁, x₂) ∣ (y₁, y₂) ↔ x₁ ∣ y₁ ∧ x₂ ∣ y₂ := prod_dvd_iff instance [DecompositionMonoid G₁] [DecompositionMonoid G₂] : DecompositionMonoid (G₁ × G₂) where primal a b c h := by simp_rw [prod_dvd_iff] at h ⊢ obtain ⟨a₁, a₁', h₁, h₁', eq₁⟩ := DecompositionMonoid.primal a.1 h.1 obtain ⟨a₂, a₂', h₂, h₂', eq₂⟩ := DecompositionMonoid.primal a.2 h.2 -- aesop works here exact ⟨(a₁, a₂), (a₁', a₂'), ⟨h₁, h₂⟩, ⟨h₁', h₂'⟩, Prod.ext eq₁ eq₂⟩
Mathlib/Algebra/Divisibility/Prod.lean
35
36
theorem pi_dvd_iff {x y : ∀ i, G i} : x ∣ y ↔ ∀ i, x i ∣ y i := by
simp_rw [dvd_def, Function.funext_iff, Classical.skolem]; rfl
426
import Mathlib.Mathport.Rename #align_import init.data.list.instances from "leanprover-community/lean"@"9af482290ef68e8aaa5ead01aa7b09b7be7019fd" universe u v w namespace List variable {α : Type u} {β : Type v} {γ : Type w} -- Porting note (#10618): simp can prove this -- @[simp] theorem bind_singleton (f : α → List β) (x : α) : [x].bind f = f x := append_nil (f x) #align list.bind_singleton List.bind_singleton @[simp] theorem bind_singleton' (l : List α) : (l.bind fun x => [x]) = l := by induction l <;> simp [*] #align list.bind_singleton' List.bind_singleton'
Mathlib/Init/Data/List/Instances.lean
30
32
theorem map_eq_bind {α β} (f : α → β) (l : List α) : map f l = l.bind fun x => [f x] := by
simp only [← map_singleton] rw [← bind_singleton' l, bind_map, bind_singleton']
427
import Mathlib.Mathport.Rename #align_import init.data.list.instances from "leanprover-community/lean"@"9af482290ef68e8aaa5ead01aa7b09b7be7019fd" universe u v w namespace List variable {α : Type u} {β : Type v} {γ : Type w} -- Porting note (#10618): simp can prove this -- @[simp] theorem bind_singleton (f : α → List β) (x : α) : [x].bind f = f x := append_nil (f x) #align list.bind_singleton List.bind_singleton @[simp] theorem bind_singleton' (l : List α) : (l.bind fun x => [x]) = l := by induction l <;> simp [*] #align list.bind_singleton' List.bind_singleton' theorem map_eq_bind {α β} (f : α → β) (l : List α) : map f l = l.bind fun x => [f x] := by simp only [← map_singleton] rw [← bind_singleton' l, bind_map, bind_singleton'] #align list.map_eq_bind List.map_eq_bind
Mathlib/Init/Data/List/Instances.lean
35
36
theorem bind_assoc {α β} (l : List α) (f : α → List β) (g : β → List γ) : (l.bind f).bind g = l.bind fun x => (f x).bind g := by
induction l <;> simp [*]
427
import Mathlib.Data.Nat.Defs import Mathlib.Data.Option.Basic import Mathlib.Data.List.Defs import Mathlib.Init.Data.List.Basic import Mathlib.Init.Data.List.Instances import Mathlib.Init.Data.List.Lemmas import Mathlib.Logic.Unique import Mathlib.Order.Basic import Mathlib.Tactic.Common #align_import data.list.basic from "leanprover-community/mathlib"@"65a1391a0106c9204fe45bc73a039f056558cb83" assert_not_exists Set.range assert_not_exists GroupWithZero assert_not_exists Ring open Function open Nat hiding one_pos namespace List universe u v w variable {ι : Type*} {α : Type u} {β : Type v} {γ : Type w} {l₁ l₂ : List α} -- Porting note: Delete this attribute -- attribute [inline] List.head! instance uniqueOfIsEmpty [IsEmpty α] : Unique (List α) := { instInhabitedList with uniq := fun l => match l with | [] => rfl | a :: _ => isEmptyElim a } #align list.unique_of_is_empty List.uniqueOfIsEmpty instance : Std.LawfulIdentity (α := List α) Append.append [] where left_id := nil_append right_id := append_nil instance : Std.Associative (α := List α) Append.append where assoc := append_assoc #align list.cons_ne_nil List.cons_ne_nil #align list.cons_ne_self List.cons_ne_self #align list.head_eq_of_cons_eq List.head_eq_of_cons_eqₓ -- implicits order #align list.tail_eq_of_cons_eq List.tail_eq_of_cons_eqₓ -- implicits order @[simp] theorem cons_injective {a : α} : Injective (cons a) := fun _ _ => tail_eq_of_cons_eq #align list.cons_injective List.cons_injective #align list.cons_inj List.cons_inj #align list.cons_eq_cons List.cons_eq_cons theorem singleton_injective : Injective fun a : α => [a] := fun _ _ h => (cons_eq_cons.1 h).1 #align list.singleton_injective List.singleton_injective theorem singleton_inj {a b : α} : [a] = [b] ↔ a = b := singleton_injective.eq_iff #align list.singleton_inj List.singleton_inj #align list.exists_cons_of_ne_nil List.exists_cons_of_ne_nil theorem set_of_mem_cons (l : List α) (a : α) : { x | x ∈ a :: l } = insert a { x | x ∈ l } := Set.ext fun _ => mem_cons #align list.set_of_mem_cons List.set_of_mem_cons #align list.mem_singleton_self List.mem_singleton_self #align list.eq_of_mem_singleton List.eq_of_mem_singleton #align list.mem_singleton List.mem_singleton #align list.mem_of_mem_cons_of_mem List.mem_of_mem_cons_of_mem
Mathlib/Data/List/Basic.lean
87
91
theorem _root_.Decidable.List.eq_or_ne_mem_of_mem [DecidableEq α] {a b : α} {l : List α} (h : a ∈ b :: l) : a = b ∨ a ≠ b ∧ a ∈ l := by
by_cases hab : a = b · exact Or.inl hab · exact ((List.mem_cons.1 h).elim Or.inl (fun h => Or.inr ⟨hab, h⟩))
428
import Mathlib.Data.Nat.Defs import Mathlib.Data.Option.Basic import Mathlib.Data.List.Defs import Mathlib.Init.Data.List.Basic import Mathlib.Init.Data.List.Instances import Mathlib.Init.Data.List.Lemmas import Mathlib.Logic.Unique import Mathlib.Order.Basic import Mathlib.Tactic.Common #align_import data.list.basic from "leanprover-community/mathlib"@"65a1391a0106c9204fe45bc73a039f056558cb83" assert_not_exists Set.range assert_not_exists GroupWithZero assert_not_exists Ring open Function open Nat hiding one_pos namespace List universe u v w variable {ι : Type*} {α : Type u} {β : Type v} {γ : Type w} {l₁ l₂ : List α} -- Porting note: Delete this attribute -- attribute [inline] List.head! instance uniqueOfIsEmpty [IsEmpty α] : Unique (List α) := { instInhabitedList with uniq := fun l => match l with | [] => rfl | a :: _ => isEmptyElim a } #align list.unique_of_is_empty List.uniqueOfIsEmpty instance : Std.LawfulIdentity (α := List α) Append.append [] where left_id := nil_append right_id := append_nil instance : Std.Associative (α := List α) Append.append where assoc := append_assoc #align list.cons_ne_nil List.cons_ne_nil #align list.cons_ne_self List.cons_ne_self #align list.head_eq_of_cons_eq List.head_eq_of_cons_eqₓ -- implicits order #align list.tail_eq_of_cons_eq List.tail_eq_of_cons_eqₓ -- implicits order @[simp] theorem cons_injective {a : α} : Injective (cons a) := fun _ _ => tail_eq_of_cons_eq #align list.cons_injective List.cons_injective #align list.cons_inj List.cons_inj #align list.cons_eq_cons List.cons_eq_cons theorem singleton_injective : Injective fun a : α => [a] := fun _ _ h => (cons_eq_cons.1 h).1 #align list.singleton_injective List.singleton_injective theorem singleton_inj {a b : α} : [a] = [b] ↔ a = b := singleton_injective.eq_iff #align list.singleton_inj List.singleton_inj #align list.exists_cons_of_ne_nil List.exists_cons_of_ne_nil theorem set_of_mem_cons (l : List α) (a : α) : { x | x ∈ a :: l } = insert a { x | x ∈ l } := Set.ext fun _ => mem_cons #align list.set_of_mem_cons List.set_of_mem_cons #align list.mem_singleton_self List.mem_singleton_self #align list.eq_of_mem_singleton List.eq_of_mem_singleton #align list.mem_singleton List.mem_singleton #align list.mem_of_mem_cons_of_mem List.mem_of_mem_cons_of_mem theorem _root_.Decidable.List.eq_or_ne_mem_of_mem [DecidableEq α] {a b : α} {l : List α} (h : a ∈ b :: l) : a = b ∨ a ≠ b ∧ a ∈ l := by by_cases hab : a = b · exact Or.inl hab · exact ((List.mem_cons.1 h).elim Or.inl (fun h => Or.inr ⟨hab, h⟩)) #align decidable.list.eq_or_ne_mem_of_mem Decidable.List.eq_or_ne_mem_of_mem #align list.eq_or_ne_mem_of_mem List.eq_or_ne_mem_of_mem #align list.not_mem_append List.not_mem_append #align list.ne_nil_of_mem List.ne_nil_of_mem lemma mem_pair {a b c : α} : a ∈ [b, c] ↔ a = b ∨ a = c := by rw [mem_cons, mem_singleton] @[deprecated (since := "2024-03-23")] alias mem_split := append_of_mem #align list.mem_split List.append_of_mem #align list.mem_of_ne_of_mem List.mem_of_ne_of_mem #align list.ne_of_not_mem_cons List.ne_of_not_mem_cons #align list.not_mem_of_not_mem_cons List.not_mem_of_not_mem_cons #align list.not_mem_cons_of_ne_of_not_mem List.not_mem_cons_of_ne_of_not_mem #align list.ne_and_not_mem_of_not_mem_cons List.ne_and_not_mem_of_not_mem_cons #align list.mem_map List.mem_map #align list.exists_of_mem_map List.exists_of_mem_map #align list.mem_map_of_mem List.mem_map_of_memₓ -- implicits order -- The simpNF linter says that the LHS can be simplified via `List.mem_map`. -- However this is a higher priority lemma. -- https://github.com/leanprover/std4/issues/207 @[simp 1100, nolint simpNF] theorem mem_map_of_injective {f : α → β} (H : Injective f) {a : α} {l : List α} : f a ∈ map f l ↔ a ∈ l := ⟨fun m => let ⟨_, m', e⟩ := exists_of_mem_map m; H e ▸ m', mem_map_of_mem _⟩ #align list.mem_map_of_injective List.mem_map_of_injective @[simp] theorem _root_.Function.Involutive.exists_mem_and_apply_eq_iff {f : α → α} (hf : Function.Involutive f) (x : α) (l : List α) : (∃ y : α, y ∈ l ∧ f y = x) ↔ f x ∈ l := ⟨by rintro ⟨y, h, rfl⟩; rwa [hf y], fun h => ⟨f x, h, hf _⟩⟩ #align function.involutive.exists_mem_and_apply_eq_iff Function.Involutive.exists_mem_and_apply_eq_iff
Mathlib/Data/List/Basic.lean
137
138
theorem mem_map_of_involutive {f : α → α} (hf : Involutive f) {a : α} {l : List α} : a ∈ map f l ↔ f a ∈ l := by
rw [mem_map, hf.exists_mem_and_apply_eq_iff]
428
import Mathlib.Data.List.Basic import Mathlib.Data.Sigma.Basic #align_import data.list.prod_sigma from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" variable {α β : Type*} namespace List @[simp] theorem nil_product (l : List β) : (@nil α) ×ˢ l = [] := rfl #align list.nil_product List.nil_product @[simp] theorem product_cons (a : α) (l₁ : List α) (l₂ : List β) : (a :: l₁) ×ˢ l₂ = map (fun b => (a, b)) l₂ ++ (l₁ ×ˢ l₂) := rfl #align list.product_cons List.product_cons @[simp] theorem product_nil : ∀ l : List α, l ×ˢ (@nil β) = [] | [] => rfl | _ :: l => by simp [product_cons, product_nil l] #align list.product_nil List.product_nil @[simp]
Mathlib/Data/List/ProdSigma.lean
45
48
theorem mem_product {l₁ : List α} {l₂ : List β} {a : α} {b : β} : (a, b) ∈ l₁ ×ˢ l₂ ↔ a ∈ l₁ ∧ b ∈ l₂ := by
simp_all [SProd.sprod, product, mem_bind, mem_map, Prod.ext_iff, exists_prop, and_left_comm, exists_and_left, exists_eq_left, exists_eq_right]
429
import Mathlib.Data.List.Basic import Mathlib.Data.Sigma.Basic #align_import data.list.prod_sigma from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" variable {α β : Type*} namespace List @[simp] theorem nil_product (l : List β) : (@nil α) ×ˢ l = [] := rfl #align list.nil_product List.nil_product @[simp] theorem product_cons (a : α) (l₁ : List α) (l₂ : List β) : (a :: l₁) ×ˢ l₂ = map (fun b => (a, b)) l₂ ++ (l₁ ×ˢ l₂) := rfl #align list.product_cons List.product_cons @[simp] theorem product_nil : ∀ l : List α, l ×ˢ (@nil β) = [] | [] => rfl | _ :: l => by simp [product_cons, product_nil l] #align list.product_nil List.product_nil @[simp] theorem mem_product {l₁ : List α} {l₂ : List β} {a : α} {b : β} : (a, b) ∈ l₁ ×ˢ l₂ ↔ a ∈ l₁ ∧ b ∈ l₂ := by simp_all [SProd.sprod, product, mem_bind, mem_map, Prod.ext_iff, exists_prop, and_left_comm, exists_and_left, exists_eq_left, exists_eq_right] #align list.mem_product List.mem_product
Mathlib/Data/List/ProdSigma.lean
51
56
theorem length_product (l₁ : List α) (l₂ : List β) : length (l₁ ×ˢ l₂) = length l₁ * length l₂ := by
induction' l₁ with x l₁ IH · exact (Nat.zero_mul _).symm · simp only [length, product_cons, length_append, IH, Nat.add_mul, Nat.one_mul, length_map, Nat.add_comm]
429
import Mathlib.Data.List.Basic import Mathlib.Data.Sigma.Basic #align_import data.list.prod_sigma from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" variable {α β : Type*} namespace List @[simp] theorem nil_product (l : List β) : (@nil α) ×ˢ l = [] := rfl #align list.nil_product List.nil_product @[simp] theorem product_cons (a : α) (l₁ : List α) (l₂ : List β) : (a :: l₁) ×ˢ l₂ = map (fun b => (a, b)) l₂ ++ (l₁ ×ˢ l₂) := rfl #align list.product_cons List.product_cons @[simp] theorem product_nil : ∀ l : List α, l ×ˢ (@nil β) = [] | [] => rfl | _ :: l => by simp [product_cons, product_nil l] #align list.product_nil List.product_nil @[simp] theorem mem_product {l₁ : List α} {l₂ : List β} {a : α} {b : β} : (a, b) ∈ l₁ ×ˢ l₂ ↔ a ∈ l₁ ∧ b ∈ l₂ := by simp_all [SProd.sprod, product, mem_bind, mem_map, Prod.ext_iff, exists_prop, and_left_comm, exists_and_left, exists_eq_left, exists_eq_right] #align list.mem_product List.mem_product theorem length_product (l₁ : List α) (l₂ : List β) : length (l₁ ×ˢ l₂) = length l₁ * length l₂ := by induction' l₁ with x l₁ IH · exact (Nat.zero_mul _).symm · simp only [length, product_cons, length_append, IH, Nat.add_mul, Nat.one_mul, length_map, Nat.add_comm] #align list.length_product List.length_product variable {σ : α → Type*} @[simp] theorem nil_sigma (l : ∀ a, List (σ a)) : (@nil α).sigma l = [] := rfl #align list.nil_sigma List.nil_sigma @[simp] theorem sigma_cons (a : α) (l₁ : List α) (l₂ : ∀ a, List (σ a)) : (a :: l₁).sigma l₂ = map (Sigma.mk a) (l₂ a) ++ l₁.sigma l₂ := rfl #align list.sigma_cons List.sigma_cons @[simp] theorem sigma_nil : ∀ l : List α, (l.sigma fun a => @nil (σ a)) = [] | [] => rfl | _ :: l => by simp [sigma_cons, sigma_nil l] #align list.sigma_nil List.sigma_nil @[simp]
Mathlib/Data/List/ProdSigma.lean
82
85
theorem mem_sigma {l₁ : List α} {l₂ : ∀ a, List (σ a)} {a : α} {b : σ a} : Sigma.mk a b ∈ l₁.sigma l₂ ↔ a ∈ l₁ ∧ b ∈ l₂ a := by
simp [List.sigma, mem_bind, mem_map, exists_prop, exists_and_left, and_left_comm, exists_eq_left, heq_iff_eq, exists_eq_right]
429
import Mathlib.Data.List.Basic import Mathlib.Data.Sigma.Basic #align_import data.list.prod_sigma from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" variable {α β : Type*} namespace List @[simp] theorem nil_product (l : List β) : (@nil α) ×ˢ l = [] := rfl #align list.nil_product List.nil_product @[simp] theorem product_cons (a : α) (l₁ : List α) (l₂ : List β) : (a :: l₁) ×ˢ l₂ = map (fun b => (a, b)) l₂ ++ (l₁ ×ˢ l₂) := rfl #align list.product_cons List.product_cons @[simp] theorem product_nil : ∀ l : List α, l ×ˢ (@nil β) = [] | [] => rfl | _ :: l => by simp [product_cons, product_nil l] #align list.product_nil List.product_nil @[simp] theorem mem_product {l₁ : List α} {l₂ : List β} {a : α} {b : β} : (a, b) ∈ l₁ ×ˢ l₂ ↔ a ∈ l₁ ∧ b ∈ l₂ := by simp_all [SProd.sprod, product, mem_bind, mem_map, Prod.ext_iff, exists_prop, and_left_comm, exists_and_left, exists_eq_left, exists_eq_right] #align list.mem_product List.mem_product theorem length_product (l₁ : List α) (l₂ : List β) : length (l₁ ×ˢ l₂) = length l₁ * length l₂ := by induction' l₁ with x l₁ IH · exact (Nat.zero_mul _).symm · simp only [length, product_cons, length_append, IH, Nat.add_mul, Nat.one_mul, length_map, Nat.add_comm] #align list.length_product List.length_product variable {σ : α → Type*} @[simp] theorem nil_sigma (l : ∀ a, List (σ a)) : (@nil α).sigma l = [] := rfl #align list.nil_sigma List.nil_sigma @[simp] theorem sigma_cons (a : α) (l₁ : List α) (l₂ : ∀ a, List (σ a)) : (a :: l₁).sigma l₂ = map (Sigma.mk a) (l₂ a) ++ l₁.sigma l₂ := rfl #align list.sigma_cons List.sigma_cons @[simp] theorem sigma_nil : ∀ l : List α, (l.sigma fun a => @nil (σ a)) = [] | [] => rfl | _ :: l => by simp [sigma_cons, sigma_nil l] #align list.sigma_nil List.sigma_nil @[simp] theorem mem_sigma {l₁ : List α} {l₂ : ∀ a, List (σ a)} {a : α} {b : σ a} : Sigma.mk a b ∈ l₁.sigma l₂ ↔ a ∈ l₁ ∧ b ∈ l₂ a := by simp [List.sigma, mem_bind, mem_map, exists_prop, exists_and_left, and_left_comm, exists_eq_left, heq_iff_eq, exists_eq_right] #align list.mem_sigma List.mem_sigma
Mathlib/Data/List/ProdSigma.lean
89
93
theorem length_sigma' (l₁ : List α) (l₂ : ∀ a, List (σ a)) : length (l₁.sigma l₂) = Nat.sum (l₁.map fun a ↦ length (l₂ a)) := by
induction' l₁ with x l₁ IH · rfl · simp only [map, sigma_cons, length_append, length_map, IH, Nat.sum_cons]
429
import Mathlib.Data.List.Basic #align_import data.list.count from "leanprover-community/mathlib"@"65a1391a0106c9204fe45bc73a039f056558cb83" assert_not_exists Set.range assert_not_exists GroupWithZero assert_not_exists Ring open Nat variable {α : Type*} {l : List α} namespace List section CountP variable (p q : α → Bool) #align list.countp_nil List.countP_nil #align list.countp_cons_of_pos List.countP_cons_of_pos #align list.countp_cons_of_neg List.countP_cons_of_neg #align list.countp_cons List.countP_cons #align list.length_eq_countp_add_countp List.length_eq_countP_add_countP #align list.countp_eq_length_filter List.countP_eq_length_filter #align list.countp_le_length List.countP_le_length #align list.countp_append List.countP_append #align list.countp_pos List.countP_pos #align list.countp_eq_zero List.countP_eq_zero #align list.countp_eq_length List.countP_eq_length
Mathlib/Data/List/Count.lean
54
57
theorem length_filter_lt_length_iff_exists (l) : length (filter p l) < length l ↔ ∃ x ∈ l, ¬p x := by
simpa [length_eq_countP_add_countP p l, countP_eq_length_filter] using countP_pos (fun x => ¬p x) (l := l)
430
import Mathlib.Data.List.Basic #align_import data.list.count from "leanprover-community/mathlib"@"65a1391a0106c9204fe45bc73a039f056558cb83" assert_not_exists Set.range assert_not_exists GroupWithZero assert_not_exists Ring open Nat variable {α : Type*} {l : List α} namespace List section Count variable [DecidableEq α] #align list.count_nil List.count_nil @[deprecated (since := "2023-08-23")]
Mathlib/Data/List/Count.lean
90
93
theorem count_cons' (a b : α) (l : List α) : count a (b :: l) = count a l + if a = b then 1 else 0 := by
simp only [count, beq_iff_eq, countP_cons, Nat.add_right_inj] simp only [eq_comm]
430
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp]
Mathlib/Data/List/Enum.lean
30
31
theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by
rw [enum, get?_enumFrom, Nat.zero_add]
431
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp] theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by rw [enum, get?_enumFrom, Nat.zero_add] #align list.enum_nth List.get?_enum @[deprecated (since := "2024-04-06")] alias enum_get? := get?_enum @[simp] theorem enumFrom_map_snd : ∀ (n) (l : List α), map Prod.snd (enumFrom n l) = l | _, [] => rfl | _, _ :: _ => congr_arg (cons _) (enumFrom_map_snd _ _) #align list.enum_from_map_snd List.enumFrom_map_snd @[simp] theorem enum_map_snd (l : List α) : map Prod.snd (enum l) = l := enumFrom_map_snd _ _ #align list.enum_map_snd List.enum_map_snd @[simp]
Mathlib/Data/List/Enum.lean
48
50
theorem get_enumFrom (l : List α) (n) (i : Fin (l.enumFrom n).length) : (l.enumFrom n).get i = (n + i, l.get (i.cast enumFrom_length)) := by
simp [get_eq_get?]
431
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp] theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by rw [enum, get?_enumFrom, Nat.zero_add] #align list.enum_nth List.get?_enum @[deprecated (since := "2024-04-06")] alias enum_get? := get?_enum @[simp] theorem enumFrom_map_snd : ∀ (n) (l : List α), map Prod.snd (enumFrom n l) = l | _, [] => rfl | _, _ :: _ => congr_arg (cons _) (enumFrom_map_snd _ _) #align list.enum_from_map_snd List.enumFrom_map_snd @[simp] theorem enum_map_snd (l : List α) : map Prod.snd (enum l) = l := enumFrom_map_snd _ _ #align list.enum_map_snd List.enum_map_snd @[simp] theorem get_enumFrom (l : List α) (n) (i : Fin (l.enumFrom n).length) : (l.enumFrom n).get i = (n + i, l.get (i.cast enumFrom_length)) := by simp [get_eq_get?] #align list.nth_le_enum_from List.get_enumFrom @[simp]
Mathlib/Data/List/Enum.lean
54
56
theorem get_enum (l : List α) (i : Fin l.enum.length) : l.enum.get i = (i.1, l.get (i.cast enum_length)) := by
simp [enum]
431
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp] theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by rw [enum, get?_enumFrom, Nat.zero_add] #align list.enum_nth List.get?_enum @[deprecated (since := "2024-04-06")] alias enum_get? := get?_enum @[simp] theorem enumFrom_map_snd : ∀ (n) (l : List α), map Prod.snd (enumFrom n l) = l | _, [] => rfl | _, _ :: _ => congr_arg (cons _) (enumFrom_map_snd _ _) #align list.enum_from_map_snd List.enumFrom_map_snd @[simp] theorem enum_map_snd (l : List α) : map Prod.snd (enum l) = l := enumFrom_map_snd _ _ #align list.enum_map_snd List.enum_map_snd @[simp] theorem get_enumFrom (l : List α) (n) (i : Fin (l.enumFrom n).length) : (l.enumFrom n).get i = (n + i, l.get (i.cast enumFrom_length)) := by simp [get_eq_get?] #align list.nth_le_enum_from List.get_enumFrom @[simp] theorem get_enum (l : List α) (i : Fin l.enum.length) : l.enum.get i = (i.1, l.get (i.cast enum_length)) := by simp [enum] #align list.nth_le_enum List.get_enum
Mathlib/Data/List/Enum.lean
59
61
theorem mk_add_mem_enumFrom_iff_get? {n i : ℕ} {x : α} {l : List α} : (n + i, x) ∈ enumFrom n l ↔ l.get? i = x := by
simp [mem_iff_get?]
431
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp] theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by rw [enum, get?_enumFrom, Nat.zero_add] #align list.enum_nth List.get?_enum @[deprecated (since := "2024-04-06")] alias enum_get? := get?_enum @[simp] theorem enumFrom_map_snd : ∀ (n) (l : List α), map Prod.snd (enumFrom n l) = l | _, [] => rfl | _, _ :: _ => congr_arg (cons _) (enumFrom_map_snd _ _) #align list.enum_from_map_snd List.enumFrom_map_snd @[simp] theorem enum_map_snd (l : List α) : map Prod.snd (enum l) = l := enumFrom_map_snd _ _ #align list.enum_map_snd List.enum_map_snd @[simp] theorem get_enumFrom (l : List α) (n) (i : Fin (l.enumFrom n).length) : (l.enumFrom n).get i = (n + i, l.get (i.cast enumFrom_length)) := by simp [get_eq_get?] #align list.nth_le_enum_from List.get_enumFrom @[simp] theorem get_enum (l : List α) (i : Fin l.enum.length) : l.enum.get i = (i.1, l.get (i.cast enum_length)) := by simp [enum] #align list.nth_le_enum List.get_enum theorem mk_add_mem_enumFrom_iff_get? {n i : ℕ} {x : α} {l : List α} : (n + i, x) ∈ enumFrom n l ↔ l.get? i = x := by simp [mem_iff_get?]
Mathlib/Data/List/Enum.lean
63
70
theorem mk_mem_enumFrom_iff_le_and_get?_sub {n i : ℕ} {x : α} {l : List α} : (i, x) ∈ enumFrom n l ↔ n ≤ i ∧ l.get? (i - n) = x := by
if h : n ≤ i then rcases Nat.exists_eq_add_of_le h with ⟨i, rfl⟩ simp [mk_add_mem_enumFrom_iff_get?, Nat.add_sub_cancel_left] else have : ∀ k, n + k ≠ i := by rintro k rfl; simp at h simp [h, mem_iff_get?, this]
431
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp] theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by rw [enum, get?_enumFrom, Nat.zero_add] #align list.enum_nth List.get?_enum @[deprecated (since := "2024-04-06")] alias enum_get? := get?_enum @[simp] theorem enumFrom_map_snd : ∀ (n) (l : List α), map Prod.snd (enumFrom n l) = l | _, [] => rfl | _, _ :: _ => congr_arg (cons _) (enumFrom_map_snd _ _) #align list.enum_from_map_snd List.enumFrom_map_snd @[simp] theorem enum_map_snd (l : List α) : map Prod.snd (enum l) = l := enumFrom_map_snd _ _ #align list.enum_map_snd List.enum_map_snd @[simp] theorem get_enumFrom (l : List α) (n) (i : Fin (l.enumFrom n).length) : (l.enumFrom n).get i = (n + i, l.get (i.cast enumFrom_length)) := by simp [get_eq_get?] #align list.nth_le_enum_from List.get_enumFrom @[simp] theorem get_enum (l : List α) (i : Fin l.enum.length) : l.enum.get i = (i.1, l.get (i.cast enum_length)) := by simp [enum] #align list.nth_le_enum List.get_enum theorem mk_add_mem_enumFrom_iff_get? {n i : ℕ} {x : α} {l : List α} : (n + i, x) ∈ enumFrom n l ↔ l.get? i = x := by simp [mem_iff_get?] theorem mk_mem_enumFrom_iff_le_and_get?_sub {n i : ℕ} {x : α} {l : List α} : (i, x) ∈ enumFrom n l ↔ n ≤ i ∧ l.get? (i - n) = x := by if h : n ≤ i then rcases Nat.exists_eq_add_of_le h with ⟨i, rfl⟩ simp [mk_add_mem_enumFrom_iff_get?, Nat.add_sub_cancel_left] else have : ∀ k, n + k ≠ i := by rintro k rfl; simp at h simp [h, mem_iff_get?, this]
Mathlib/Data/List/Enum.lean
72
73
theorem mk_mem_enum_iff_get? {i : ℕ} {x : α} {l : List α} : (i, x) ∈ enum l ↔ l.get? i = x := by
simp [enum, mk_mem_enumFrom_iff_le_and_get?_sub]
431
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp] theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by rw [enum, get?_enumFrom, Nat.zero_add] #align list.enum_nth List.get?_enum @[deprecated (since := "2024-04-06")] alias enum_get? := get?_enum @[simp] theorem enumFrom_map_snd : ∀ (n) (l : List α), map Prod.snd (enumFrom n l) = l | _, [] => rfl | _, _ :: _ => congr_arg (cons _) (enumFrom_map_snd _ _) #align list.enum_from_map_snd List.enumFrom_map_snd @[simp] theorem enum_map_snd (l : List α) : map Prod.snd (enum l) = l := enumFrom_map_snd _ _ #align list.enum_map_snd List.enum_map_snd @[simp] theorem get_enumFrom (l : List α) (n) (i : Fin (l.enumFrom n).length) : (l.enumFrom n).get i = (n + i, l.get (i.cast enumFrom_length)) := by simp [get_eq_get?] #align list.nth_le_enum_from List.get_enumFrom @[simp] theorem get_enum (l : List α) (i : Fin l.enum.length) : l.enum.get i = (i.1, l.get (i.cast enum_length)) := by simp [enum] #align list.nth_le_enum List.get_enum theorem mk_add_mem_enumFrom_iff_get? {n i : ℕ} {x : α} {l : List α} : (n + i, x) ∈ enumFrom n l ↔ l.get? i = x := by simp [mem_iff_get?] theorem mk_mem_enumFrom_iff_le_and_get?_sub {n i : ℕ} {x : α} {l : List α} : (i, x) ∈ enumFrom n l ↔ n ≤ i ∧ l.get? (i - n) = x := by if h : n ≤ i then rcases Nat.exists_eq_add_of_le h with ⟨i, rfl⟩ simp [mk_add_mem_enumFrom_iff_get?, Nat.add_sub_cancel_left] else have : ∀ k, n + k ≠ i := by rintro k rfl; simp at h simp [h, mem_iff_get?, this] theorem mk_mem_enum_iff_get? {i : ℕ} {x : α} {l : List α} : (i, x) ∈ enum l ↔ l.get? i = x := by simp [enum, mk_mem_enumFrom_iff_le_and_get?_sub] theorem mem_enum_iff_get? {x : ℕ × α} {l : List α} : x ∈ enum l ↔ l.get? x.1 = x.2 := mk_mem_enum_iff_get? theorem le_fst_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : n ≤ x.1 := (mk_mem_enumFrom_iff_le_and_get?_sub.1 h).1
Mathlib/Data/List/Enum.lean
82
85
theorem fst_lt_add_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : x.1 < n + length l := by
rcases mem_iff_get.1 h with ⟨i, rfl⟩ simpa using i.is_lt
431
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp] theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by rw [enum, get?_enumFrom, Nat.zero_add] #align list.enum_nth List.get?_enum @[deprecated (since := "2024-04-06")] alias enum_get? := get?_enum @[simp] theorem enumFrom_map_snd : ∀ (n) (l : List α), map Prod.snd (enumFrom n l) = l | _, [] => rfl | _, _ :: _ => congr_arg (cons _) (enumFrom_map_snd _ _) #align list.enum_from_map_snd List.enumFrom_map_snd @[simp] theorem enum_map_snd (l : List α) : map Prod.snd (enum l) = l := enumFrom_map_snd _ _ #align list.enum_map_snd List.enum_map_snd @[simp] theorem get_enumFrom (l : List α) (n) (i : Fin (l.enumFrom n).length) : (l.enumFrom n).get i = (n + i, l.get (i.cast enumFrom_length)) := by simp [get_eq_get?] #align list.nth_le_enum_from List.get_enumFrom @[simp] theorem get_enum (l : List α) (i : Fin l.enum.length) : l.enum.get i = (i.1, l.get (i.cast enum_length)) := by simp [enum] #align list.nth_le_enum List.get_enum theorem mk_add_mem_enumFrom_iff_get? {n i : ℕ} {x : α} {l : List α} : (n + i, x) ∈ enumFrom n l ↔ l.get? i = x := by simp [mem_iff_get?] theorem mk_mem_enumFrom_iff_le_and_get?_sub {n i : ℕ} {x : α} {l : List α} : (i, x) ∈ enumFrom n l ↔ n ≤ i ∧ l.get? (i - n) = x := by if h : n ≤ i then rcases Nat.exists_eq_add_of_le h with ⟨i, rfl⟩ simp [mk_add_mem_enumFrom_iff_get?, Nat.add_sub_cancel_left] else have : ∀ k, n + k ≠ i := by rintro k rfl; simp at h simp [h, mem_iff_get?, this] theorem mk_mem_enum_iff_get? {i : ℕ} {x : α} {l : List α} : (i, x) ∈ enum l ↔ l.get? i = x := by simp [enum, mk_mem_enumFrom_iff_le_and_get?_sub] theorem mem_enum_iff_get? {x : ℕ × α} {l : List α} : x ∈ enum l ↔ l.get? x.1 = x.2 := mk_mem_enum_iff_get? theorem le_fst_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : n ≤ x.1 := (mk_mem_enumFrom_iff_le_and_get?_sub.1 h).1 theorem fst_lt_add_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : x.1 < n + length l := by rcases mem_iff_get.1 h with ⟨i, rfl⟩ simpa using i.is_lt
Mathlib/Data/List/Enum.lean
87
88
theorem fst_lt_of_mem_enum {x : ℕ × α} {l : List α} (h : x ∈ enum l) : x.1 < length l := by
simpa using fst_lt_add_of_mem_enumFrom h
431
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp] theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by rw [enum, get?_enumFrom, Nat.zero_add] #align list.enum_nth List.get?_enum @[deprecated (since := "2024-04-06")] alias enum_get? := get?_enum @[simp] theorem enumFrom_map_snd : ∀ (n) (l : List α), map Prod.snd (enumFrom n l) = l | _, [] => rfl | _, _ :: _ => congr_arg (cons _) (enumFrom_map_snd _ _) #align list.enum_from_map_snd List.enumFrom_map_snd @[simp] theorem enum_map_snd (l : List α) : map Prod.snd (enum l) = l := enumFrom_map_snd _ _ #align list.enum_map_snd List.enum_map_snd @[simp] theorem get_enumFrom (l : List α) (n) (i : Fin (l.enumFrom n).length) : (l.enumFrom n).get i = (n + i, l.get (i.cast enumFrom_length)) := by simp [get_eq_get?] #align list.nth_le_enum_from List.get_enumFrom @[simp] theorem get_enum (l : List α) (i : Fin l.enum.length) : l.enum.get i = (i.1, l.get (i.cast enum_length)) := by simp [enum] #align list.nth_le_enum List.get_enum theorem mk_add_mem_enumFrom_iff_get? {n i : ℕ} {x : α} {l : List α} : (n + i, x) ∈ enumFrom n l ↔ l.get? i = x := by simp [mem_iff_get?] theorem mk_mem_enumFrom_iff_le_and_get?_sub {n i : ℕ} {x : α} {l : List α} : (i, x) ∈ enumFrom n l ↔ n ≤ i ∧ l.get? (i - n) = x := by if h : n ≤ i then rcases Nat.exists_eq_add_of_le h with ⟨i, rfl⟩ simp [mk_add_mem_enumFrom_iff_get?, Nat.add_sub_cancel_left] else have : ∀ k, n + k ≠ i := by rintro k rfl; simp at h simp [h, mem_iff_get?, this] theorem mk_mem_enum_iff_get? {i : ℕ} {x : α} {l : List α} : (i, x) ∈ enum l ↔ l.get? i = x := by simp [enum, mk_mem_enumFrom_iff_le_and_get?_sub] theorem mem_enum_iff_get? {x : ℕ × α} {l : List α} : x ∈ enum l ↔ l.get? x.1 = x.2 := mk_mem_enum_iff_get? theorem le_fst_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : n ≤ x.1 := (mk_mem_enumFrom_iff_le_and_get?_sub.1 h).1 theorem fst_lt_add_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : x.1 < n + length l := by rcases mem_iff_get.1 h with ⟨i, rfl⟩ simpa using i.is_lt theorem fst_lt_of_mem_enum {x : ℕ × α} {l : List α} (h : x ∈ enum l) : x.1 < length l := by simpa using fst_lt_add_of_mem_enumFrom h theorem snd_mem_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : x.2 ∈ l := enumFrom_map_snd n l ▸ mem_map_of_mem _ h theorem snd_mem_of_mem_enum {x : ℕ × α} {l : List α} (h : x ∈ enum l) : x.2 ∈ l := snd_mem_of_mem_enumFrom h theorem mem_enumFrom {x : α} {i j : ℕ} (xs : List α) (h : (i, x) ∈ xs.enumFrom j) : j ≤ i ∧ i < j + xs.length ∧ x ∈ xs := ⟨le_fst_of_mem_enumFrom h, fst_lt_add_of_mem_enumFrom h, snd_mem_of_mem_enumFrom h⟩ #align list.mem_enum_from List.mem_enumFrom @[simp] theorem enum_nil : enum ([] : List α) = [] := rfl #align list.enum_nil List.enum_nil #align list.enum_from_nil List.enumFrom_nil #align list.enum_from_cons List.enumFrom_cons @[simp] theorem enum_cons (x : α) (xs : List α) : enum (x :: xs) = (0, x) :: enumFrom 1 xs := rfl #align list.enum_cons List.enum_cons @[simp] theorem enumFrom_singleton (x : α) (n : ℕ) : enumFrom n [x] = [(n, x)] := rfl #align list.enum_from_singleton List.enumFrom_singleton @[simp] theorem enum_singleton (x : α) : enum [x] = [(0, x)] := rfl #align list.enum_singleton List.enum_singleton
Mathlib/Data/List/Enum.lean
124
129
theorem enumFrom_append (xs ys : List α) (n : ℕ) : enumFrom n (xs ++ ys) = enumFrom n xs ++ enumFrom (n + xs.length) ys := by
induction' xs with x xs IH generalizing ys n · simp · rw [cons_append, enumFrom_cons, IH, ← cons_append, ← enumFrom_cons, length, Nat.add_right_comm, Nat.add_assoc]
431
import Mathlib.Data.List.Basic namespace List variable {α β : Type*} #align list.length_enum_from List.enumFrom_length #align list.length_enum List.enum_length @[simp] theorem get?_enumFrom : ∀ n (l : List α) m, get? (enumFrom n l) m = (get? l m).map fun a => (n + m, a) | n, [], m => rfl | n, a :: l, 0 => rfl | n, a :: l, m + 1 => (get?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl #align list.enum_from_nth List.get?_enumFrom @[deprecated (since := "2024-04-06")] alias enumFrom_get? := get?_enumFrom @[simp] theorem get?_enum (l : List α) (n) : get? (enum l) n = (get? l n).map fun a => (n, a) := by rw [enum, get?_enumFrom, Nat.zero_add] #align list.enum_nth List.get?_enum @[deprecated (since := "2024-04-06")] alias enum_get? := get?_enum @[simp] theorem enumFrom_map_snd : ∀ (n) (l : List α), map Prod.snd (enumFrom n l) = l | _, [] => rfl | _, _ :: _ => congr_arg (cons _) (enumFrom_map_snd _ _) #align list.enum_from_map_snd List.enumFrom_map_snd @[simp] theorem enum_map_snd (l : List α) : map Prod.snd (enum l) = l := enumFrom_map_snd _ _ #align list.enum_map_snd List.enum_map_snd @[simp] theorem get_enumFrom (l : List α) (n) (i : Fin (l.enumFrom n).length) : (l.enumFrom n).get i = (n + i, l.get (i.cast enumFrom_length)) := by simp [get_eq_get?] #align list.nth_le_enum_from List.get_enumFrom @[simp] theorem get_enum (l : List α) (i : Fin l.enum.length) : l.enum.get i = (i.1, l.get (i.cast enum_length)) := by simp [enum] #align list.nth_le_enum List.get_enum theorem mk_add_mem_enumFrom_iff_get? {n i : ℕ} {x : α} {l : List α} : (n + i, x) ∈ enumFrom n l ↔ l.get? i = x := by simp [mem_iff_get?] theorem mk_mem_enumFrom_iff_le_and_get?_sub {n i : ℕ} {x : α} {l : List α} : (i, x) ∈ enumFrom n l ↔ n ≤ i ∧ l.get? (i - n) = x := by if h : n ≤ i then rcases Nat.exists_eq_add_of_le h with ⟨i, rfl⟩ simp [mk_add_mem_enumFrom_iff_get?, Nat.add_sub_cancel_left] else have : ∀ k, n + k ≠ i := by rintro k rfl; simp at h simp [h, mem_iff_get?, this] theorem mk_mem_enum_iff_get? {i : ℕ} {x : α} {l : List α} : (i, x) ∈ enum l ↔ l.get? i = x := by simp [enum, mk_mem_enumFrom_iff_le_and_get?_sub] theorem mem_enum_iff_get? {x : ℕ × α} {l : List α} : x ∈ enum l ↔ l.get? x.1 = x.2 := mk_mem_enum_iff_get? theorem le_fst_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : n ≤ x.1 := (mk_mem_enumFrom_iff_le_and_get?_sub.1 h).1 theorem fst_lt_add_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : x.1 < n + length l := by rcases mem_iff_get.1 h with ⟨i, rfl⟩ simpa using i.is_lt theorem fst_lt_of_mem_enum {x : ℕ × α} {l : List α} (h : x ∈ enum l) : x.1 < length l := by simpa using fst_lt_add_of_mem_enumFrom h theorem snd_mem_of_mem_enumFrom {x : ℕ × α} {n : ℕ} {l : List α} (h : x ∈ enumFrom n l) : x.2 ∈ l := enumFrom_map_snd n l ▸ mem_map_of_mem _ h theorem snd_mem_of_mem_enum {x : ℕ × α} {l : List α} (h : x ∈ enum l) : x.2 ∈ l := snd_mem_of_mem_enumFrom h theorem mem_enumFrom {x : α} {i j : ℕ} (xs : List α) (h : (i, x) ∈ xs.enumFrom j) : j ≤ i ∧ i < j + xs.length ∧ x ∈ xs := ⟨le_fst_of_mem_enumFrom h, fst_lt_add_of_mem_enumFrom h, snd_mem_of_mem_enumFrom h⟩ #align list.mem_enum_from List.mem_enumFrom @[simp] theorem enum_nil : enum ([] : List α) = [] := rfl #align list.enum_nil List.enum_nil #align list.enum_from_nil List.enumFrom_nil #align list.enum_from_cons List.enumFrom_cons @[simp] theorem enum_cons (x : α) (xs : List α) : enum (x :: xs) = (0, x) :: enumFrom 1 xs := rfl #align list.enum_cons List.enum_cons @[simp] theorem enumFrom_singleton (x : α) (n : ℕ) : enumFrom n [x] = [(n, x)] := rfl #align list.enum_from_singleton List.enumFrom_singleton @[simp] theorem enum_singleton (x : α) : enum [x] = [(0, x)] := rfl #align list.enum_singleton List.enum_singleton theorem enumFrom_append (xs ys : List α) (n : ℕ) : enumFrom n (xs ++ ys) = enumFrom n xs ++ enumFrom (n + xs.length) ys := by induction' xs with x xs IH generalizing ys n · simp · rw [cons_append, enumFrom_cons, IH, ← cons_append, ← enumFrom_cons, length, Nat.add_right_comm, Nat.add_assoc] #align list.enum_from_append List.enumFrom_append
Mathlib/Data/List/Enum.lean
132
133
theorem enum_append (xs ys : List α) : enum (xs ++ ys) = enum xs ++ enumFrom xs.length ys := by
simp [enum, enumFrom_append]
431
import Mathlib.Data.List.Basic #align_import data.bool.all_any from "leanprover-community/mathlib"@"5a3e819569b0f12cbec59d740a2613018e7b8eec" variable {α : Type*} {p : α → Prop} [DecidablePred p] {l : List α} {a : α} namespace List -- Porting note: in Batteries #align list.all_nil List.all_nil #align list.all_cons List.all_consₓ
Mathlib/Data/Bool/AllAny.lean
27
30
theorem all_iff_forall {p : α → Bool} : all l p ↔ ∀ a ∈ l, p a := by
induction' l with a l ih · exact iff_of_true rfl (forall_mem_nil _) simp only [all_cons, Bool.and_eq_true_iff, ih, forall_mem_cons]
432
import Mathlib.Data.List.Basic #align_import data.bool.all_any from "leanprover-community/mathlib"@"5a3e819569b0f12cbec59d740a2613018e7b8eec" variable {α : Type*} {p : α → Prop} [DecidablePred p] {l : List α} {a : α} namespace List -- Porting note: in Batteries #align list.all_nil List.all_nil #align list.all_cons List.all_consₓ theorem all_iff_forall {p : α → Bool} : all l p ↔ ∀ a ∈ l, p a := by induction' l with a l ih · exact iff_of_true rfl (forall_mem_nil _) simp only [all_cons, Bool.and_eq_true_iff, ih, forall_mem_cons] #align list.all_iff_forall List.all_iff_forall
Mathlib/Data/Bool/AllAny.lean
33
34
theorem all_iff_forall_prop : (all l fun a => p a) ↔ ∀ a ∈ l, p a := by
simp only [all_iff_forall, decide_eq_true_iff]
432
import Mathlib.Data.List.Basic #align_import data.bool.all_any from "leanprover-community/mathlib"@"5a3e819569b0f12cbec59d740a2613018e7b8eec" variable {α : Type*} {p : α → Prop} [DecidablePred p] {l : List α} {a : α} namespace List -- Porting note: in Batteries #align list.all_nil List.all_nil #align list.all_cons List.all_consₓ theorem all_iff_forall {p : α → Bool} : all l p ↔ ∀ a ∈ l, p a := by induction' l with a l ih · exact iff_of_true rfl (forall_mem_nil _) simp only [all_cons, Bool.and_eq_true_iff, ih, forall_mem_cons] #align list.all_iff_forall List.all_iff_forall theorem all_iff_forall_prop : (all l fun a => p a) ↔ ∀ a ∈ l, p a := by simp only [all_iff_forall, decide_eq_true_iff] #align list.all_iff_forall_prop List.all_iff_forall_prop -- Porting note: in Batteries #align list.any_nil List.any_nil #align list.any_cons List.any_consₓ
Mathlib/Data/Bool/AllAny.lean
42
45
theorem any_iff_exists {p : α → Bool} : any l p ↔ ∃ a ∈ l, p a := by
induction' l with a l ih · exact iff_of_false Bool.false_ne_true (not_exists_mem_nil _) simp only [any_cons, Bool.or_eq_true_iff, ih, exists_mem_cons_iff]
432
import Mathlib.Data.List.Basic #align_import data.bool.all_any from "leanprover-community/mathlib"@"5a3e819569b0f12cbec59d740a2613018e7b8eec" variable {α : Type*} {p : α → Prop} [DecidablePred p] {l : List α} {a : α} namespace List -- Porting note: in Batteries #align list.all_nil List.all_nil #align list.all_cons List.all_consₓ theorem all_iff_forall {p : α → Bool} : all l p ↔ ∀ a ∈ l, p a := by induction' l with a l ih · exact iff_of_true rfl (forall_mem_nil _) simp only [all_cons, Bool.and_eq_true_iff, ih, forall_mem_cons] #align list.all_iff_forall List.all_iff_forall theorem all_iff_forall_prop : (all l fun a => p a) ↔ ∀ a ∈ l, p a := by simp only [all_iff_forall, decide_eq_true_iff] #align list.all_iff_forall_prop List.all_iff_forall_prop -- Porting note: in Batteries #align list.any_nil List.any_nil #align list.any_cons List.any_consₓ theorem any_iff_exists {p : α → Bool} : any l p ↔ ∃ a ∈ l, p a := by induction' l with a l ih · exact iff_of_false Bool.false_ne_true (not_exists_mem_nil _) simp only [any_cons, Bool.or_eq_true_iff, ih, exists_mem_cons_iff] #align list.any_iff_exists List.any_iff_exists
Mathlib/Data/Bool/AllAny.lean
48
48
theorem any_iff_exists_prop : (any l fun a => p a) ↔ ∃ a ∈ l, p a := by
simp [any_iff_exists]
432
import Mathlib.Logic.Pairwise import Mathlib.Logic.Relation import Mathlib.Data.List.Basic #align_import data.list.pairwise from "leanprover-community/mathlib"@"f694c7dead66f5d4c80f446c796a5aad14707f0e" open Nat Function namespace List variable {α β : Type*} {R S T : α → α → Prop} {a : α} {l : List α} mk_iff_of_inductive_prop List.Pairwise List.pairwise_iff #align list.pairwise_iff List.pairwise_iff #align list.pairwise.nil List.Pairwise.nil #align list.pairwise.cons List.Pairwise.cons #align list.rel_of_pairwise_cons List.rel_of_pairwise_cons #align list.pairwise.of_cons List.Pairwise.of_cons #align list.pairwise.tail List.Pairwise.tail #align list.pairwise.drop List.Pairwise.drop #align list.pairwise.imp_of_mem List.Pairwise.imp_of_mem #align list.pairwise.imp List.Pairwise.impₓ -- Implicits Order #align list.pairwise_and_iff List.pairwise_and_iff #align list.pairwise.and List.Pairwise.and #align list.pairwise.imp₂ List.Pairwise.imp₂ #align list.pairwise.iff_of_mem List.Pairwise.iff_of_mem #align list.pairwise.iff List.Pairwise.iff #align list.pairwise_of_forall List.pairwise_of_forall #align list.pairwise.and_mem List.Pairwise.and_mem #align list.pairwise.imp_mem List.Pairwise.imp_mem #align list.pairwise.sublist List.Pairwise.sublistₓ -- Implicits order #align list.pairwise.forall_of_forall_of_flip List.Pairwise.forall_of_forall_of_flip theorem Pairwise.forall_of_forall (H : Symmetric R) (H₁ : ∀ x ∈ l, R x x) (H₂ : l.Pairwise R) : ∀ ⦃x⦄, x ∈ l → ∀ ⦃y⦄, y ∈ l → R x y := H₂.forall_of_forall_of_flip H₁ <| by rwa [H.flip_eq] #align list.pairwise.forall_of_forall List.Pairwise.forall_of_forall
Mathlib/Data/List/Pairwise.lean
81
86
theorem Pairwise.forall (hR : Symmetric R) (hl : l.Pairwise R) : ∀ ⦃a⦄, a ∈ l → ∀ ⦃b⦄, b ∈ l → a ≠ b → R a b := by
apply Pairwise.forall_of_forall · exact fun a b h hne => hR (h hne.symm) · exact fun _ _ hx => (hx rfl).elim · exact hl.imp (@fun a b h _ => by exact h)
433
import Mathlib.Logic.Pairwise import Mathlib.Logic.Relation import Mathlib.Data.List.Basic #align_import data.list.pairwise from "leanprover-community/mathlib"@"f694c7dead66f5d4c80f446c796a5aad14707f0e" open Nat Function namespace List variable {α β : Type*} {R S T : α → α → Prop} {a : α} {l : List α} mk_iff_of_inductive_prop List.Pairwise List.pairwise_iff #align list.pairwise_iff List.pairwise_iff #align list.pairwise.nil List.Pairwise.nil #align list.pairwise.cons List.Pairwise.cons #align list.rel_of_pairwise_cons List.rel_of_pairwise_cons #align list.pairwise.of_cons List.Pairwise.of_cons #align list.pairwise.tail List.Pairwise.tail #align list.pairwise.drop List.Pairwise.drop #align list.pairwise.imp_of_mem List.Pairwise.imp_of_mem #align list.pairwise.imp List.Pairwise.impₓ -- Implicits Order #align list.pairwise_and_iff List.pairwise_and_iff #align list.pairwise.and List.Pairwise.and #align list.pairwise.imp₂ List.Pairwise.imp₂ #align list.pairwise.iff_of_mem List.Pairwise.iff_of_mem #align list.pairwise.iff List.Pairwise.iff #align list.pairwise_of_forall List.pairwise_of_forall #align list.pairwise.and_mem List.Pairwise.and_mem #align list.pairwise.imp_mem List.Pairwise.imp_mem #align list.pairwise.sublist List.Pairwise.sublistₓ -- Implicits order #align list.pairwise.forall_of_forall_of_flip List.Pairwise.forall_of_forall_of_flip theorem Pairwise.forall_of_forall (H : Symmetric R) (H₁ : ∀ x ∈ l, R x x) (H₂ : l.Pairwise R) : ∀ ⦃x⦄, x ∈ l → ∀ ⦃y⦄, y ∈ l → R x y := H₂.forall_of_forall_of_flip H₁ <| by rwa [H.flip_eq] #align list.pairwise.forall_of_forall List.Pairwise.forall_of_forall theorem Pairwise.forall (hR : Symmetric R) (hl : l.Pairwise R) : ∀ ⦃a⦄, a ∈ l → ∀ ⦃b⦄, b ∈ l → a ≠ b → R a b := by apply Pairwise.forall_of_forall · exact fun a b h hne => hR (h hne.symm) · exact fun _ _ hx => (hx rfl).elim · exact hl.imp (@fun a b h _ => by exact h) #align list.pairwise.forall List.Pairwise.forall theorem Pairwise.set_pairwise (hl : Pairwise R l) (hr : Symmetric R) : { x | x ∈ l }.Pairwise R := hl.forall hr #align list.pairwise.set_pairwise List.Pairwise.set_pairwise #align list.pairwise_singleton List.pairwise_singleton #align list.pairwise_pair List.pairwise_pair #align list.pairwise_append List.pairwise_append #align list.pairwise_append_comm List.pairwise_append_comm #align list.pairwise_middle List.pairwise_middle -- Porting note: Duplicate of `pairwise_map` but with `f` explicit. @[deprecated (since := "2024-02-25")] theorem pairwise_map' (f : β → α) : ∀ {l : List β}, Pairwise R (map f l) ↔ Pairwise (fun a b : β => R (f a) (f b)) l | [] => by simp only [map, Pairwise.nil] | b :: l => by simp only [map, pairwise_cons, mem_map, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂, pairwise_map] #align list.pairwise_map List.pairwise_map' #align list.pairwise.of_map List.Pairwise.of_map #align list.pairwise.map List.Pairwise.map #align list.pairwise_filter_map List.pairwise_filterMap #align list.pairwise.filter_map List.Pairwise.filter_map #align list.pairwise_filter List.pairwise_filter #align list.pairwise.filter List.Pairwise.filterₓ
Mathlib/Data/List/Pairwise.lean
124
133
theorem pairwise_pmap {p : β → Prop} {f : ∀ b, p b → α} {l : List β} (h : ∀ x ∈ l, p x) : Pairwise R (l.pmap f h) ↔ Pairwise (fun b₁ b₂ => ∀ (h₁ : p b₁) (h₂ : p b₂), R (f b₁ h₁) (f b₂ h₂)) l := by
induction' l with a l ihl · simp obtain ⟨_, hl⟩ : p a ∧ ∀ b, b ∈ l → p b := by simpa using h simp only [ihl hl, pairwise_cons, exists₂_imp, pmap, and_congr_left_iff, mem_pmap] refine fun _ => ⟨fun H b hb _ hpb => H _ _ hb rfl, ?_⟩ rintro H _ b hb rfl exact H b hb _ _
433
import Mathlib.Logic.Pairwise import Mathlib.Logic.Relation import Mathlib.Data.List.Basic #align_import data.list.pairwise from "leanprover-community/mathlib"@"f694c7dead66f5d4c80f446c796a5aad14707f0e" open Nat Function namespace List variable {α β : Type*} {R S T : α → α → Prop} {a : α} {l : List α} mk_iff_of_inductive_prop List.Pairwise List.pairwise_iff #align list.pairwise_iff List.pairwise_iff #align list.pairwise.nil List.Pairwise.nil #align list.pairwise.cons List.Pairwise.cons #align list.rel_of_pairwise_cons List.rel_of_pairwise_cons #align list.pairwise.of_cons List.Pairwise.of_cons #align list.pairwise.tail List.Pairwise.tail #align list.pairwise.drop List.Pairwise.drop #align list.pairwise.imp_of_mem List.Pairwise.imp_of_mem #align list.pairwise.imp List.Pairwise.impₓ -- Implicits Order #align list.pairwise_and_iff List.pairwise_and_iff #align list.pairwise.and List.Pairwise.and #align list.pairwise.imp₂ List.Pairwise.imp₂ #align list.pairwise.iff_of_mem List.Pairwise.iff_of_mem #align list.pairwise.iff List.Pairwise.iff #align list.pairwise_of_forall List.pairwise_of_forall #align list.pairwise.and_mem List.Pairwise.and_mem #align list.pairwise.imp_mem List.Pairwise.imp_mem #align list.pairwise.sublist List.Pairwise.sublistₓ -- Implicits order #align list.pairwise.forall_of_forall_of_flip List.Pairwise.forall_of_forall_of_flip theorem Pairwise.forall_of_forall (H : Symmetric R) (H₁ : ∀ x ∈ l, R x x) (H₂ : l.Pairwise R) : ∀ ⦃x⦄, x ∈ l → ∀ ⦃y⦄, y ∈ l → R x y := H₂.forall_of_forall_of_flip H₁ <| by rwa [H.flip_eq] #align list.pairwise.forall_of_forall List.Pairwise.forall_of_forall theorem Pairwise.forall (hR : Symmetric R) (hl : l.Pairwise R) : ∀ ⦃a⦄, a ∈ l → ∀ ⦃b⦄, b ∈ l → a ≠ b → R a b := by apply Pairwise.forall_of_forall · exact fun a b h hne => hR (h hne.symm) · exact fun _ _ hx => (hx rfl).elim · exact hl.imp (@fun a b h _ => by exact h) #align list.pairwise.forall List.Pairwise.forall theorem Pairwise.set_pairwise (hl : Pairwise R l) (hr : Symmetric R) : { x | x ∈ l }.Pairwise R := hl.forall hr #align list.pairwise.set_pairwise List.Pairwise.set_pairwise #align list.pairwise_singleton List.pairwise_singleton #align list.pairwise_pair List.pairwise_pair #align list.pairwise_append List.pairwise_append #align list.pairwise_append_comm List.pairwise_append_comm #align list.pairwise_middle List.pairwise_middle -- Porting note: Duplicate of `pairwise_map` but with `f` explicit. @[deprecated (since := "2024-02-25")] theorem pairwise_map' (f : β → α) : ∀ {l : List β}, Pairwise R (map f l) ↔ Pairwise (fun a b : β => R (f a) (f b)) l | [] => by simp only [map, Pairwise.nil] | b :: l => by simp only [map, pairwise_cons, mem_map, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂, pairwise_map] #align list.pairwise_map List.pairwise_map' #align list.pairwise.of_map List.Pairwise.of_map #align list.pairwise.map List.Pairwise.map #align list.pairwise_filter_map List.pairwise_filterMap #align list.pairwise.filter_map List.Pairwise.filter_map #align list.pairwise_filter List.pairwise_filter #align list.pairwise.filter List.Pairwise.filterₓ theorem pairwise_pmap {p : β → Prop} {f : ∀ b, p b → α} {l : List β} (h : ∀ x ∈ l, p x) : Pairwise R (l.pmap f h) ↔ Pairwise (fun b₁ b₂ => ∀ (h₁ : p b₁) (h₂ : p b₂), R (f b₁ h₁) (f b₂ h₂)) l := by induction' l with a l ihl · simp obtain ⟨_, hl⟩ : p a ∧ ∀ b, b ∈ l → p b := by simpa using h simp only [ihl hl, pairwise_cons, exists₂_imp, pmap, and_congr_left_iff, mem_pmap] refine fun _ => ⟨fun H b hb _ hpb => H _ _ hb rfl, ?_⟩ rintro H _ b hb rfl exact H b hb _ _ #align list.pairwise_pmap List.pairwise_pmap
Mathlib/Data/List/Pairwise.lean
136
141
theorem Pairwise.pmap {l : List α} (hl : Pairwise R l) {p : α → Prop} {f : ∀ a, p a → β} (h : ∀ x ∈ l, p x) {S : β → β → Prop} (hS : ∀ ⦃x⦄ (hx : p x) ⦃y⦄ (hy : p y), R x y → S (f x hx) (f y hy)) : Pairwise S (l.pmap f h) := by
refine (pairwise_pmap h).2 (Pairwise.imp_of_mem ?_ hl) intros; apply hS; assumption
433
import Mathlib.Logic.Pairwise import Mathlib.Logic.Relation import Mathlib.Data.List.Basic #align_import data.list.pairwise from "leanprover-community/mathlib"@"f694c7dead66f5d4c80f446c796a5aad14707f0e" open Nat Function namespace List variable {α β : Type*} {R S T : α → α → Prop} {a : α} {l : List α} mk_iff_of_inductive_prop List.Pairwise List.pairwise_iff #align list.pairwise_iff List.pairwise_iff #align list.pairwise.nil List.Pairwise.nil #align list.pairwise.cons List.Pairwise.cons #align list.rel_of_pairwise_cons List.rel_of_pairwise_cons #align list.pairwise.of_cons List.Pairwise.of_cons #align list.pairwise.tail List.Pairwise.tail #align list.pairwise.drop List.Pairwise.drop #align list.pairwise.imp_of_mem List.Pairwise.imp_of_mem #align list.pairwise.imp List.Pairwise.impₓ -- Implicits Order #align list.pairwise_and_iff List.pairwise_and_iff #align list.pairwise.and List.Pairwise.and #align list.pairwise.imp₂ List.Pairwise.imp₂ #align list.pairwise.iff_of_mem List.Pairwise.iff_of_mem #align list.pairwise.iff List.Pairwise.iff #align list.pairwise_of_forall List.pairwise_of_forall #align list.pairwise.and_mem List.Pairwise.and_mem #align list.pairwise.imp_mem List.Pairwise.imp_mem #align list.pairwise.sublist List.Pairwise.sublistₓ -- Implicits order #align list.pairwise.forall_of_forall_of_flip List.Pairwise.forall_of_forall_of_flip theorem Pairwise.forall_of_forall (H : Symmetric R) (H₁ : ∀ x ∈ l, R x x) (H₂ : l.Pairwise R) : ∀ ⦃x⦄, x ∈ l → ∀ ⦃y⦄, y ∈ l → R x y := H₂.forall_of_forall_of_flip H₁ <| by rwa [H.flip_eq] #align list.pairwise.forall_of_forall List.Pairwise.forall_of_forall theorem Pairwise.forall (hR : Symmetric R) (hl : l.Pairwise R) : ∀ ⦃a⦄, a ∈ l → ∀ ⦃b⦄, b ∈ l → a ≠ b → R a b := by apply Pairwise.forall_of_forall · exact fun a b h hne => hR (h hne.symm) · exact fun _ _ hx => (hx rfl).elim · exact hl.imp (@fun a b h _ => by exact h) #align list.pairwise.forall List.Pairwise.forall theorem Pairwise.set_pairwise (hl : Pairwise R l) (hr : Symmetric R) : { x | x ∈ l }.Pairwise R := hl.forall hr #align list.pairwise.set_pairwise List.Pairwise.set_pairwise #align list.pairwise_singleton List.pairwise_singleton #align list.pairwise_pair List.pairwise_pair #align list.pairwise_append List.pairwise_append #align list.pairwise_append_comm List.pairwise_append_comm #align list.pairwise_middle List.pairwise_middle -- Porting note: Duplicate of `pairwise_map` but with `f` explicit. @[deprecated (since := "2024-02-25")] theorem pairwise_map' (f : β → α) : ∀ {l : List β}, Pairwise R (map f l) ↔ Pairwise (fun a b : β => R (f a) (f b)) l | [] => by simp only [map, Pairwise.nil] | b :: l => by simp only [map, pairwise_cons, mem_map, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂, pairwise_map] #align list.pairwise_map List.pairwise_map' #align list.pairwise.of_map List.Pairwise.of_map #align list.pairwise.map List.Pairwise.map #align list.pairwise_filter_map List.pairwise_filterMap #align list.pairwise.filter_map List.Pairwise.filter_map #align list.pairwise_filter List.pairwise_filter #align list.pairwise.filter List.Pairwise.filterₓ theorem pairwise_pmap {p : β → Prop} {f : ∀ b, p b → α} {l : List β} (h : ∀ x ∈ l, p x) : Pairwise R (l.pmap f h) ↔ Pairwise (fun b₁ b₂ => ∀ (h₁ : p b₁) (h₂ : p b₂), R (f b₁ h₁) (f b₂ h₂)) l := by induction' l with a l ihl · simp obtain ⟨_, hl⟩ : p a ∧ ∀ b, b ∈ l → p b := by simpa using h simp only [ihl hl, pairwise_cons, exists₂_imp, pmap, and_congr_left_iff, mem_pmap] refine fun _ => ⟨fun H b hb _ hpb => H _ _ hb rfl, ?_⟩ rintro H _ b hb rfl exact H b hb _ _ #align list.pairwise_pmap List.pairwise_pmap theorem Pairwise.pmap {l : List α} (hl : Pairwise R l) {p : α → Prop} {f : ∀ a, p a → β} (h : ∀ x ∈ l, p x) {S : β → β → Prop} (hS : ∀ ⦃x⦄ (hx : p x) ⦃y⦄ (hy : p y), R x y → S (f x hx) (f y hy)) : Pairwise S (l.pmap f h) := by refine (pairwise_pmap h).2 (Pairwise.imp_of_mem ?_ hl) intros; apply hS; assumption #align list.pairwise.pmap List.Pairwise.pmap #align list.pairwise_join List.pairwise_join #align list.pairwise_bind List.pairwise_bind #align list.pairwise_reverse List.pairwise_reverse #align list.pairwise_of_reflexive_on_dupl_of_forall_ne List.pairwise_of_reflexive_on_dupl_of_forall_ne
Mathlib/Data/List/Pairwise.lean
152
156
theorem pairwise_of_forall_mem_list {l : List α} {r : α → α → Prop} (h : ∀ a ∈ l, ∀ b ∈ l, r a b) : l.Pairwise r := by
rw [pairwise_iff_forall_sublist] intro a b hab apply h <;> (apply hab.subset; simp)
433
import Mathlib.Data.List.Basic #align_import data.list.palindrome from "leanprover-community/mathlib"@"5a3e819569b0f12cbec59d740a2613018e7b8eec" variable {α β : Type*} namespace List inductive Palindrome : List α → Prop | nil : Palindrome [] | singleton : ∀ x, Palindrome [x] | cons_concat : ∀ (x) {l}, Palindrome l → Palindrome (x :: (l ++ [x])) #align list.palindrome List.Palindrome namespace Palindrome variable {l : List α}
Mathlib/Data/List/Palindrome.lean
50
52
theorem reverse_eq {l : List α} (p : Palindrome l) : reverse l = l := by
induction p <;> try (exact rfl) simpa
434
import Mathlib.Data.List.Basic #align_import data.list.palindrome from "leanprover-community/mathlib"@"5a3e819569b0f12cbec59d740a2613018e7b8eec" variable {α β : Type*} namespace List inductive Palindrome : List α → Prop | nil : Palindrome [] | singleton : ∀ x, Palindrome [x] | cons_concat : ∀ (x) {l}, Palindrome l → Palindrome (x :: (l ++ [x])) #align list.palindrome List.Palindrome namespace Palindrome variable {l : List α} theorem reverse_eq {l : List α} (p : Palindrome l) : reverse l = l := by induction p <;> try (exact rfl) simpa #align list.palindrome.reverse_eq List.Palindrome.reverse_eq
Mathlib/Data/List/Palindrome.lean
55
61
theorem of_reverse_eq {l : List α} : reverse l = l → Palindrome l := by
refine bidirectionalRecOn l (fun _ => Palindrome.nil) (fun a _ => Palindrome.singleton a) ?_ intro x l y hp hr rw [reverse_cons, reverse_append] at hr rw [head_eq_of_cons_eq hr] have : Palindrome l := hp (append_inj_left' (tail_eq_of_cons_eq hr) rfl) exact Palindrome.cons_concat x this
434
import Mathlib.Data.List.Basic #align_import data.list.palindrome from "leanprover-community/mathlib"@"5a3e819569b0f12cbec59d740a2613018e7b8eec" variable {α β : Type*} namespace List inductive Palindrome : List α → Prop | nil : Palindrome [] | singleton : ∀ x, Palindrome [x] | cons_concat : ∀ (x) {l}, Palindrome l → Palindrome (x :: (l ++ [x])) #align list.palindrome List.Palindrome namespace Palindrome variable {l : List α} theorem reverse_eq {l : List α} (p : Palindrome l) : reverse l = l := by induction p <;> try (exact rfl) simpa #align list.palindrome.reverse_eq List.Palindrome.reverse_eq theorem of_reverse_eq {l : List α} : reverse l = l → Palindrome l := by refine bidirectionalRecOn l (fun _ => Palindrome.nil) (fun a _ => Palindrome.singleton a) ?_ intro x l y hp hr rw [reverse_cons, reverse_append] at hr rw [head_eq_of_cons_eq hr] have : Palindrome l := hp (append_inj_left' (tail_eq_of_cons_eq hr) rfl) exact Palindrome.cons_concat x this #align list.palindrome.of_reverse_eq List.Palindrome.of_reverse_eq theorem iff_reverse_eq {l : List α} : Palindrome l ↔ reverse l = l := Iff.intro reverse_eq of_reverse_eq #align list.palindrome.iff_reverse_eq List.Palindrome.iff_reverse_eq
Mathlib/Data/List/Palindrome.lean
68
70
theorem append_reverse (l : List α) : Palindrome (l ++ reverse l) := by
apply of_reverse_eq rw [reverse_append, reverse_reverse]
434
import Mathlib.Data.List.Basic #align_import data.list.forall2 from "leanprover-community/mathlib"@"5a3e819569b0f12cbec59d740a2613018e7b8eec" open Nat Function namespace List variable {α β γ δ : Type*} {R S : α → β → Prop} {P : γ → δ → Prop} {Rₐ : α → α → Prop} open Relator mk_iff_of_inductive_prop List.Forall₂ List.forall₂_iff #align list.forall₂_iff List.forall₂_iff #align list.forall₂.nil List.Forall₂.nil #align list.forall₂.cons List.Forall₂.cons #align list.forall₂_cons List.forall₂_cons
Mathlib/Data/List/Forall2.lean
34
35
theorem Forall₂.imp (H : ∀ a b, R a b → S a b) {l₁ l₂} (h : Forall₂ R l₁ l₂) : Forall₂ S l₁ l₂ := by
induction h <;> constructor <;> solve_by_elim
435
import Mathlib.Data.List.Basic #align_import data.list.forall2 from "leanprover-community/mathlib"@"5a3e819569b0f12cbec59d740a2613018e7b8eec" open Nat Function namespace List variable {α β γ δ : Type*} {R S : α → β → Prop} {P : γ → δ → Prop} {Rₐ : α → α → Prop} open Relator mk_iff_of_inductive_prop List.Forall₂ List.forall₂_iff #align list.forall₂_iff List.forall₂_iff #align list.forall₂.nil List.Forall₂.nil #align list.forall₂.cons List.Forall₂.cons #align list.forall₂_cons List.forall₂_cons theorem Forall₂.imp (H : ∀ a b, R a b → S a b) {l₁ l₂} (h : Forall₂ R l₁ l₂) : Forall₂ S l₁ l₂ := by induction h <;> constructor <;> solve_by_elim #align list.forall₂.imp List.Forall₂.imp theorem Forall₂.mp {Q : α → β → Prop} (h : ∀ a b, Q a b → R a b → S a b) : ∀ {l₁ l₂}, Forall₂ Q l₁ l₂ → Forall₂ R l₁ l₂ → Forall₂ S l₁ l₂ | [], [], Forall₂.nil, Forall₂.nil => Forall₂.nil | a :: _, b :: _, Forall₂.cons hr hrs, Forall₂.cons hq hqs => Forall₂.cons (h a b hr hq) (Forall₂.mp h hrs hqs) #align list.forall₂.mp List.Forall₂.mp theorem Forall₂.flip : ∀ {a b}, Forall₂ (flip R) b a → Forall₂ R a b | _, _, Forall₂.nil => Forall₂.nil | _ :: _, _ :: _, Forall₂.cons h₁ h₂ => Forall₂.cons h₁ h₂.flip #align list.forall₂.flip List.Forall₂.flip @[simp] theorem forall₂_same : ∀ {l : List α}, Forall₂ Rₐ l l ↔ ∀ x ∈ l, Rₐ x x | [] => by simp | a :: l => by simp [@forall₂_same l] #align list.forall₂_same List.forall₂_same theorem forall₂_refl [IsRefl α Rₐ] (l : List α) : Forall₂ Rₐ l l := forall₂_same.2 fun _ _ => refl _ #align list.forall₂_refl List.forall₂_refl @[simp]
Mathlib/Data/List/Forall2.lean
61
69
theorem forall₂_eq_eq_eq : Forall₂ ((· = ·) : α → α → Prop) = Eq := by
funext a b; apply propext constructor · intro h induction h · rfl simp only [*] · rintro rfl exact forall₂_refl _
435
import Mathlib.Data.List.Forall2 #align_import data.list.sections from "leanprover-community/mathlib"@"26f081a2fb920140ed5bc5cc5344e84bcc7cb2b2" open Nat Function namespace List variable {α β : Type*}
Mathlib/Data/List/Sections.lean
23
34
theorem mem_sections {L : List (List α)} {f} : f ∈ sections L ↔ Forall₂ (· ∈ ·) f L := by
refine ⟨fun h => ?_, fun h => ?_⟩ · induction L generalizing f · cases mem_singleton.1 h exact Forall₂.nil simp only [sections, bind_eq_bind, mem_bind, mem_map] at h rcases h with ⟨_, _, _, _, rfl⟩ simp only [*, forall₂_cons, true_and_iff] · induction' h with a l f L al fL fs · simp only [sections, mem_singleton] simp only [sections, bind_eq_bind, mem_bind, mem_map] exact ⟨f, fs, a, al, rfl⟩
436
import Mathlib.Data.List.Forall2 #align_import data.list.zip from "leanprover-community/mathlib"@"134625f523e737f650a6ea7f0c82a6177e45e622" -- Make sure we don't import algebra assert_not_exists Monoid universe u open Nat namespace List variable {α : Type u} {β γ δ ε : Type*} #align list.zip_with_cons_cons List.zipWith_cons_cons #align list.zip_cons_cons List.zip_cons_cons #align list.zip_with_nil_left List.zipWith_nil_left #align list.zip_with_nil_right List.zipWith_nil_right #align list.zip_with_eq_nil_iff List.zipWith_eq_nil_iff #align list.zip_nil_left List.zip_nil_left #align list.zip_nil_right List.zip_nil_right @[simp] theorem zip_swap : ∀ (l₁ : List α) (l₂ : List β), (zip l₁ l₂).map Prod.swap = zip l₂ l₁ | [], l₂ => zip_nil_right.symm | l₁, [] => by rw [zip_nil_right]; rfl | a :: l₁, b :: l₂ => by simp only [zip_cons_cons, map_cons, zip_swap l₁ l₂, Prod.swap_prod_mk] #align list.zip_swap List.zip_swap #align list.length_zip_with List.length_zipWith #align list.length_zip List.length_zip theorem forall_zipWith {f : α → β → γ} {p : γ → Prop} : ∀ {l₁ : List α} {l₂ : List β}, length l₁ = length l₂ → (Forall p (zipWith f l₁ l₂) ↔ Forall₂ (fun x y => p (f x y)) l₁ l₂) | [], [], _ => by simp | a :: l₁, b :: l₂, h => by simp only [length_cons, succ_inj'] at h simp [forall_zipWith h] #align list.all₂_zip_with List.forall_zipWith
Mathlib/Data/List/Zip.lean
63
64
theorem lt_length_left_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l.length := by
rw [length_zipWith] at h; omega
437
import Mathlib.Data.List.Forall2 #align_import data.list.zip from "leanprover-community/mathlib"@"134625f523e737f650a6ea7f0c82a6177e45e622" -- Make sure we don't import algebra assert_not_exists Monoid universe u open Nat namespace List variable {α : Type u} {β γ δ ε : Type*} #align list.zip_with_cons_cons List.zipWith_cons_cons #align list.zip_cons_cons List.zip_cons_cons #align list.zip_with_nil_left List.zipWith_nil_left #align list.zip_with_nil_right List.zipWith_nil_right #align list.zip_with_eq_nil_iff List.zipWith_eq_nil_iff #align list.zip_nil_left List.zip_nil_left #align list.zip_nil_right List.zip_nil_right @[simp] theorem zip_swap : ∀ (l₁ : List α) (l₂ : List β), (zip l₁ l₂).map Prod.swap = zip l₂ l₁ | [], l₂ => zip_nil_right.symm | l₁, [] => by rw [zip_nil_right]; rfl | a :: l₁, b :: l₂ => by simp only [zip_cons_cons, map_cons, zip_swap l₁ l₂, Prod.swap_prod_mk] #align list.zip_swap List.zip_swap #align list.length_zip_with List.length_zipWith #align list.length_zip List.length_zip theorem forall_zipWith {f : α → β → γ} {p : γ → Prop} : ∀ {l₁ : List α} {l₂ : List β}, length l₁ = length l₂ → (Forall p (zipWith f l₁ l₂) ↔ Forall₂ (fun x y => p (f x y)) l₁ l₂) | [], [], _ => by simp | a :: l₁, b :: l₂, h => by simp only [length_cons, succ_inj'] at h simp [forall_zipWith h] #align list.all₂_zip_with List.forall_zipWith theorem lt_length_left_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l.length := by rw [length_zipWith] at h; omega #align list.lt_length_left_of_zip_with List.lt_length_left_of_zipWith
Mathlib/Data/List/Zip.lean
67
68
theorem lt_length_right_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l'.length := by
rw [length_zipWith] at h; omega
437
import Mathlib.Data.List.Forall2 #align_import data.list.zip from "leanprover-community/mathlib"@"134625f523e737f650a6ea7f0c82a6177e45e622" -- Make sure we don't import algebra assert_not_exists Monoid universe u open Nat namespace List variable {α : Type u} {β γ δ ε : Type*} #align list.zip_with_cons_cons List.zipWith_cons_cons #align list.zip_cons_cons List.zip_cons_cons #align list.zip_with_nil_left List.zipWith_nil_left #align list.zip_with_nil_right List.zipWith_nil_right #align list.zip_with_eq_nil_iff List.zipWith_eq_nil_iff #align list.zip_nil_left List.zip_nil_left #align list.zip_nil_right List.zip_nil_right @[simp] theorem zip_swap : ∀ (l₁ : List α) (l₂ : List β), (zip l₁ l₂).map Prod.swap = zip l₂ l₁ | [], l₂ => zip_nil_right.symm | l₁, [] => by rw [zip_nil_right]; rfl | a :: l₁, b :: l₂ => by simp only [zip_cons_cons, map_cons, zip_swap l₁ l₂, Prod.swap_prod_mk] #align list.zip_swap List.zip_swap #align list.length_zip_with List.length_zipWith #align list.length_zip List.length_zip theorem forall_zipWith {f : α → β → γ} {p : γ → Prop} : ∀ {l₁ : List α} {l₂ : List β}, length l₁ = length l₂ → (Forall p (zipWith f l₁ l₂) ↔ Forall₂ (fun x y => p (f x y)) l₁ l₂) | [], [], _ => by simp | a :: l₁, b :: l₂, h => by simp only [length_cons, succ_inj'] at h simp [forall_zipWith h] #align list.all₂_zip_with List.forall_zipWith theorem lt_length_left_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l.length := by rw [length_zipWith] at h; omega #align list.lt_length_left_of_zip_with List.lt_length_left_of_zipWith theorem lt_length_right_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l'.length := by rw [length_zipWith] at h; omega #align list.lt_length_right_of_zip_with List.lt_length_right_of_zipWith theorem lt_length_left_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l.length := lt_length_left_of_zipWith h #align list.lt_length_left_of_zip List.lt_length_left_of_zip theorem lt_length_right_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l'.length := lt_length_right_of_zipWith h #align list.lt_length_right_of_zip List.lt_length_right_of_zip #align list.zip_append List.zip_append #align list.zip_map List.zip_map #align list.zip_map_left List.zip_map_left #align list.zip_map_right List.zip_map_right #align list.zip_with_map List.zipWith_map #align list.zip_with_map_left List.zipWith_map_left #align list.zip_with_map_right List.zipWith_map_right #align list.zip_map' List.zip_map' #align list.map_zip_with List.map_zipWith theorem mem_zip {a b} : ∀ {l₁ : List α} {l₂ : List β}, (a, b) ∈ zip l₁ l₂ → a ∈ l₁ ∧ b ∈ l₂ | _ :: l₁, _ :: l₂, h => by cases' h with _ _ _ h · simp · have := mem_zip h exact ⟨Mem.tail _ this.1, Mem.tail _ this.2⟩ #align list.mem_zip List.mem_zip #align list.map_fst_zip List.map_fst_zip #align list.map_snd_zip List.map_snd_zip #align list.unzip_nil List.unzip_nil #align list.unzip_cons List.unzip_cons theorem unzip_eq_map : ∀ l : List (α × β), unzip l = (l.map Prod.fst, l.map Prod.snd) | [] => rfl | (a, b) :: l => by simp only [unzip_cons, map_cons, unzip_eq_map l] #align list.unzip_eq_map List.unzip_eq_map
Mathlib/Data/List/Zip.lean
109
109
theorem unzip_left (l : List (α × β)) : (unzip l).1 = l.map Prod.fst := by
simp only [unzip_eq_map]
437
import Mathlib.Data.List.Forall2 #align_import data.list.zip from "leanprover-community/mathlib"@"134625f523e737f650a6ea7f0c82a6177e45e622" -- Make sure we don't import algebra assert_not_exists Monoid universe u open Nat namespace List variable {α : Type u} {β γ δ ε : Type*} #align list.zip_with_cons_cons List.zipWith_cons_cons #align list.zip_cons_cons List.zip_cons_cons #align list.zip_with_nil_left List.zipWith_nil_left #align list.zip_with_nil_right List.zipWith_nil_right #align list.zip_with_eq_nil_iff List.zipWith_eq_nil_iff #align list.zip_nil_left List.zip_nil_left #align list.zip_nil_right List.zip_nil_right @[simp] theorem zip_swap : ∀ (l₁ : List α) (l₂ : List β), (zip l₁ l₂).map Prod.swap = zip l₂ l₁ | [], l₂ => zip_nil_right.symm | l₁, [] => by rw [zip_nil_right]; rfl | a :: l₁, b :: l₂ => by simp only [zip_cons_cons, map_cons, zip_swap l₁ l₂, Prod.swap_prod_mk] #align list.zip_swap List.zip_swap #align list.length_zip_with List.length_zipWith #align list.length_zip List.length_zip theorem forall_zipWith {f : α → β → γ} {p : γ → Prop} : ∀ {l₁ : List α} {l₂ : List β}, length l₁ = length l₂ → (Forall p (zipWith f l₁ l₂) ↔ Forall₂ (fun x y => p (f x y)) l₁ l₂) | [], [], _ => by simp | a :: l₁, b :: l₂, h => by simp only [length_cons, succ_inj'] at h simp [forall_zipWith h] #align list.all₂_zip_with List.forall_zipWith theorem lt_length_left_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l.length := by rw [length_zipWith] at h; omega #align list.lt_length_left_of_zip_with List.lt_length_left_of_zipWith theorem lt_length_right_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l'.length := by rw [length_zipWith] at h; omega #align list.lt_length_right_of_zip_with List.lt_length_right_of_zipWith theorem lt_length_left_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l.length := lt_length_left_of_zipWith h #align list.lt_length_left_of_zip List.lt_length_left_of_zip theorem lt_length_right_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l'.length := lt_length_right_of_zipWith h #align list.lt_length_right_of_zip List.lt_length_right_of_zip #align list.zip_append List.zip_append #align list.zip_map List.zip_map #align list.zip_map_left List.zip_map_left #align list.zip_map_right List.zip_map_right #align list.zip_with_map List.zipWith_map #align list.zip_with_map_left List.zipWith_map_left #align list.zip_with_map_right List.zipWith_map_right #align list.zip_map' List.zip_map' #align list.map_zip_with List.map_zipWith theorem mem_zip {a b} : ∀ {l₁ : List α} {l₂ : List β}, (a, b) ∈ zip l₁ l₂ → a ∈ l₁ ∧ b ∈ l₂ | _ :: l₁, _ :: l₂, h => by cases' h with _ _ _ h · simp · have := mem_zip h exact ⟨Mem.tail _ this.1, Mem.tail _ this.2⟩ #align list.mem_zip List.mem_zip #align list.map_fst_zip List.map_fst_zip #align list.map_snd_zip List.map_snd_zip #align list.unzip_nil List.unzip_nil #align list.unzip_cons List.unzip_cons theorem unzip_eq_map : ∀ l : List (α × β), unzip l = (l.map Prod.fst, l.map Prod.snd) | [] => rfl | (a, b) :: l => by simp only [unzip_cons, map_cons, unzip_eq_map l] #align list.unzip_eq_map List.unzip_eq_map theorem unzip_left (l : List (α × β)) : (unzip l).1 = l.map Prod.fst := by simp only [unzip_eq_map] #align list.unzip_left List.unzip_left
Mathlib/Data/List/Zip.lean
112
112
theorem unzip_right (l : List (α × β)) : (unzip l).2 = l.map Prod.snd := by
simp only [unzip_eq_map]
437
import Mathlib.Data.List.Forall2 #align_import data.list.zip from "leanprover-community/mathlib"@"134625f523e737f650a6ea7f0c82a6177e45e622" -- Make sure we don't import algebra assert_not_exists Monoid universe u open Nat namespace List variable {α : Type u} {β γ δ ε : Type*} #align list.zip_with_cons_cons List.zipWith_cons_cons #align list.zip_cons_cons List.zip_cons_cons #align list.zip_with_nil_left List.zipWith_nil_left #align list.zip_with_nil_right List.zipWith_nil_right #align list.zip_with_eq_nil_iff List.zipWith_eq_nil_iff #align list.zip_nil_left List.zip_nil_left #align list.zip_nil_right List.zip_nil_right @[simp] theorem zip_swap : ∀ (l₁ : List α) (l₂ : List β), (zip l₁ l₂).map Prod.swap = zip l₂ l₁ | [], l₂ => zip_nil_right.symm | l₁, [] => by rw [zip_nil_right]; rfl | a :: l₁, b :: l₂ => by simp only [zip_cons_cons, map_cons, zip_swap l₁ l₂, Prod.swap_prod_mk] #align list.zip_swap List.zip_swap #align list.length_zip_with List.length_zipWith #align list.length_zip List.length_zip theorem forall_zipWith {f : α → β → γ} {p : γ → Prop} : ∀ {l₁ : List α} {l₂ : List β}, length l₁ = length l₂ → (Forall p (zipWith f l₁ l₂) ↔ Forall₂ (fun x y => p (f x y)) l₁ l₂) | [], [], _ => by simp | a :: l₁, b :: l₂, h => by simp only [length_cons, succ_inj'] at h simp [forall_zipWith h] #align list.all₂_zip_with List.forall_zipWith theorem lt_length_left_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l.length := by rw [length_zipWith] at h; omega #align list.lt_length_left_of_zip_with List.lt_length_left_of_zipWith theorem lt_length_right_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l'.length := by rw [length_zipWith] at h; omega #align list.lt_length_right_of_zip_with List.lt_length_right_of_zipWith theorem lt_length_left_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l.length := lt_length_left_of_zipWith h #align list.lt_length_left_of_zip List.lt_length_left_of_zip theorem lt_length_right_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l'.length := lt_length_right_of_zipWith h #align list.lt_length_right_of_zip List.lt_length_right_of_zip #align list.zip_append List.zip_append #align list.zip_map List.zip_map #align list.zip_map_left List.zip_map_left #align list.zip_map_right List.zip_map_right #align list.zip_with_map List.zipWith_map #align list.zip_with_map_left List.zipWith_map_left #align list.zip_with_map_right List.zipWith_map_right #align list.zip_map' List.zip_map' #align list.map_zip_with List.map_zipWith theorem mem_zip {a b} : ∀ {l₁ : List α} {l₂ : List β}, (a, b) ∈ zip l₁ l₂ → a ∈ l₁ ∧ b ∈ l₂ | _ :: l₁, _ :: l₂, h => by cases' h with _ _ _ h · simp · have := mem_zip h exact ⟨Mem.tail _ this.1, Mem.tail _ this.2⟩ #align list.mem_zip List.mem_zip #align list.map_fst_zip List.map_fst_zip #align list.map_snd_zip List.map_snd_zip #align list.unzip_nil List.unzip_nil #align list.unzip_cons List.unzip_cons theorem unzip_eq_map : ∀ l : List (α × β), unzip l = (l.map Prod.fst, l.map Prod.snd) | [] => rfl | (a, b) :: l => by simp only [unzip_cons, map_cons, unzip_eq_map l] #align list.unzip_eq_map List.unzip_eq_map theorem unzip_left (l : List (α × β)) : (unzip l).1 = l.map Prod.fst := by simp only [unzip_eq_map] #align list.unzip_left List.unzip_left theorem unzip_right (l : List (α × β)) : (unzip l).2 = l.map Prod.snd := by simp only [unzip_eq_map] #align list.unzip_right List.unzip_right
Mathlib/Data/List/Zip.lean
115
117
theorem unzip_swap (l : List (α × β)) : unzip (l.map Prod.swap) = (unzip l).swap := by
simp only [unzip_eq_map, map_map] rfl
437
import Mathlib.Data.List.Forall2 #align_import data.list.zip from "leanprover-community/mathlib"@"134625f523e737f650a6ea7f0c82a6177e45e622" -- Make sure we don't import algebra assert_not_exists Monoid universe u open Nat namespace List variable {α : Type u} {β γ δ ε : Type*} #align list.zip_with_cons_cons List.zipWith_cons_cons #align list.zip_cons_cons List.zip_cons_cons #align list.zip_with_nil_left List.zipWith_nil_left #align list.zip_with_nil_right List.zipWith_nil_right #align list.zip_with_eq_nil_iff List.zipWith_eq_nil_iff #align list.zip_nil_left List.zip_nil_left #align list.zip_nil_right List.zip_nil_right @[simp] theorem zip_swap : ∀ (l₁ : List α) (l₂ : List β), (zip l₁ l₂).map Prod.swap = zip l₂ l₁ | [], l₂ => zip_nil_right.symm | l₁, [] => by rw [zip_nil_right]; rfl | a :: l₁, b :: l₂ => by simp only [zip_cons_cons, map_cons, zip_swap l₁ l₂, Prod.swap_prod_mk] #align list.zip_swap List.zip_swap #align list.length_zip_with List.length_zipWith #align list.length_zip List.length_zip theorem forall_zipWith {f : α → β → γ} {p : γ → Prop} : ∀ {l₁ : List α} {l₂ : List β}, length l₁ = length l₂ → (Forall p (zipWith f l₁ l₂) ↔ Forall₂ (fun x y => p (f x y)) l₁ l₂) | [], [], _ => by simp | a :: l₁, b :: l₂, h => by simp only [length_cons, succ_inj'] at h simp [forall_zipWith h] #align list.all₂_zip_with List.forall_zipWith theorem lt_length_left_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l.length := by rw [length_zipWith] at h; omega #align list.lt_length_left_of_zip_with List.lt_length_left_of_zipWith theorem lt_length_right_of_zipWith {f : α → β → γ} {i : ℕ} {l : List α} {l' : List β} (h : i < (zipWith f l l').length) : i < l'.length := by rw [length_zipWith] at h; omega #align list.lt_length_right_of_zip_with List.lt_length_right_of_zipWith theorem lt_length_left_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l.length := lt_length_left_of_zipWith h #align list.lt_length_left_of_zip List.lt_length_left_of_zip theorem lt_length_right_of_zip {i : ℕ} {l : List α} {l' : List β} (h : i < (zip l l').length) : i < l'.length := lt_length_right_of_zipWith h #align list.lt_length_right_of_zip List.lt_length_right_of_zip #align list.zip_append List.zip_append #align list.zip_map List.zip_map #align list.zip_map_left List.zip_map_left #align list.zip_map_right List.zip_map_right #align list.zip_with_map List.zipWith_map #align list.zip_with_map_left List.zipWith_map_left #align list.zip_with_map_right List.zipWith_map_right #align list.zip_map' List.zip_map' #align list.map_zip_with List.map_zipWith theorem mem_zip {a b} : ∀ {l₁ : List α} {l₂ : List β}, (a, b) ∈ zip l₁ l₂ → a ∈ l₁ ∧ b ∈ l₂ | _ :: l₁, _ :: l₂, h => by cases' h with _ _ _ h · simp · have := mem_zip h exact ⟨Mem.tail _ this.1, Mem.tail _ this.2⟩ #align list.mem_zip List.mem_zip #align list.map_fst_zip List.map_fst_zip #align list.map_snd_zip List.map_snd_zip #align list.unzip_nil List.unzip_nil #align list.unzip_cons List.unzip_cons theorem unzip_eq_map : ∀ l : List (α × β), unzip l = (l.map Prod.fst, l.map Prod.snd) | [] => rfl | (a, b) :: l => by simp only [unzip_cons, map_cons, unzip_eq_map l] #align list.unzip_eq_map List.unzip_eq_map theorem unzip_left (l : List (α × β)) : (unzip l).1 = l.map Prod.fst := by simp only [unzip_eq_map] #align list.unzip_left List.unzip_left theorem unzip_right (l : List (α × β)) : (unzip l).2 = l.map Prod.snd := by simp only [unzip_eq_map] #align list.unzip_right List.unzip_right theorem unzip_swap (l : List (α × β)) : unzip (l.map Prod.swap) = (unzip l).swap := by simp only [unzip_eq_map, map_map] rfl #align list.unzip_swap List.unzip_swap theorem zip_unzip : ∀ l : List (α × β), zip (unzip l).1 (unzip l).2 = l | [] => rfl | (a, b) :: l => by simp only [unzip_cons, zip_cons_cons, zip_unzip l] #align list.zip_unzip List.zip_unzip theorem unzip_zip_left : ∀ {l₁ : List α} {l₂ : List β}, length l₁ ≤ length l₂ → (unzip (zip l₁ l₂)).1 = l₁ | [], l₂, _ => rfl | l₁, [], h => by rw [eq_nil_of_length_eq_zero (Nat.eq_zero_of_le_zero h)]; rfl | a :: l₁, b :: l₂, h => by simp only [zip_cons_cons, unzip_cons, unzip_zip_left (le_of_succ_le_succ h)] #align list.unzip_zip_left List.unzip_zip_left
Mathlib/Data/List/Zip.lean
133
134
theorem unzip_zip_right {l₁ : List α} {l₂ : List β} (h : length l₂ ≤ length l₁) : (unzip (zip l₁ l₂)).2 = l₂ := by
rw [← zip_swap, unzip_swap]; exact unzip_zip_left h
437
import Mathlib.Data.List.Basic open Function open Nat hiding one_pos assert_not_exists Set.range namespace List universe u v w variable {ι : Type*} {α : Type u} {β : Type v} {γ : Type w} {l₁ l₂ : List α} section InsertNth variable {a : α} @[simp] theorem insertNth_zero (s : List α) (x : α) : insertNth 0 x s = x :: s := rfl #align list.insert_nth_zero List.insertNth_zero @[simp] theorem insertNth_succ_nil (n : ℕ) (a : α) : insertNth (n + 1) a [] = [] := rfl #align list.insert_nth_succ_nil List.insertNth_succ_nil @[simp] theorem insertNth_succ_cons (s : List α) (hd x : α) (n : ℕ) : insertNth (n + 1) x (hd :: s) = hd :: insertNth n x s := rfl #align list.insert_nth_succ_cons List.insertNth_succ_cons theorem length_insertNth : ∀ n as, n ≤ length as → length (insertNth n a as) = length as + 1 | 0, _, _ => rfl | _ + 1, [], h => (Nat.not_succ_le_zero _ h).elim | n + 1, _ :: as, h => congr_arg Nat.succ <| length_insertNth n as (Nat.le_of_succ_le_succ h) #align list.length_insert_nth List.length_insertNth
Mathlib/Data/List/InsertNth.lean
52
54
theorem eraseIdx_insertNth (n : ℕ) (l : List α) : (l.insertNth n a).eraseIdx n = l := by
rw [eraseIdx_eq_modifyNthTail, insertNth, modifyNthTail_modifyNthTail_same] exact modifyNthTail_id _ _
438
import Mathlib.Data.List.Basic open Function open Nat hiding one_pos assert_not_exists Set.range namespace List universe u v w variable {ι : Type*} {α : Type u} {β : Type v} {γ : Type w} {l₁ l₂ : List α} section InsertNth variable {a : α} @[simp] theorem insertNth_zero (s : List α) (x : α) : insertNth 0 x s = x :: s := rfl #align list.insert_nth_zero List.insertNth_zero @[simp] theorem insertNth_succ_nil (n : ℕ) (a : α) : insertNth (n + 1) a [] = [] := rfl #align list.insert_nth_succ_nil List.insertNth_succ_nil @[simp] theorem insertNth_succ_cons (s : List α) (hd x : α) (n : ℕ) : insertNth (n + 1) x (hd :: s) = hd :: insertNth n x s := rfl #align list.insert_nth_succ_cons List.insertNth_succ_cons theorem length_insertNth : ∀ n as, n ≤ length as → length (insertNth n a as) = length as + 1 | 0, _, _ => rfl | _ + 1, [], h => (Nat.not_succ_le_zero _ h).elim | n + 1, _ :: as, h => congr_arg Nat.succ <| length_insertNth n as (Nat.le_of_succ_le_succ h) #align list.length_insert_nth List.length_insertNth theorem eraseIdx_insertNth (n : ℕ) (l : List α) : (l.insertNth n a).eraseIdx n = l := by rw [eraseIdx_eq_modifyNthTail, insertNth, modifyNthTail_modifyNthTail_same] exact modifyNthTail_id _ _ #align list.remove_nth_insert_nth List.eraseIdx_insertNth @[deprecated (since := "2024-05-04")] alias removeNth_insertNth := eraseIdx_insertNth theorem insertNth_eraseIdx_of_ge : ∀ n m as, n < length as → n ≤ m → insertNth m a (as.eraseIdx n) = (as.insertNth (m + 1) a).eraseIdx n | 0, 0, [], has, _ => (lt_irrefl _ has).elim | 0, 0, _ :: as, _, _ => by simp [eraseIdx, insertNth] | 0, m + 1, a :: as, _, _ => rfl | n + 1, m + 1, a :: as, has, hmn => congr_arg (cons a) <| insertNth_eraseIdx_of_ge n m as (Nat.lt_of_succ_lt_succ has) (Nat.le_of_succ_le_succ hmn) #align list.insert_nth_remove_nth_of_ge List.insertNth_eraseIdx_of_ge @[deprecated (since := "2024-05-04")] alias insertNth_removeNth_of_ge := insertNth_eraseIdx_of_ge theorem insertNth_eraseIdx_of_le : ∀ n m as, n < length as → m ≤ n → insertNth m a (as.eraseIdx n) = (as.insertNth m a).eraseIdx (n + 1) | _, 0, _ :: _, _, _ => rfl | n + 1, m + 1, a :: as, has, hmn => congr_arg (cons a) <| insertNth_eraseIdx_of_le n m as (Nat.lt_of_succ_lt_succ has) (Nat.le_of_succ_le_succ hmn) #align list.insert_nth_remove_nth_of_le List.insertNth_eraseIdx_of_le @[deprecated (since := "2024-05-04")] alias insertNth_removeNth_of_le := insertNth_eraseIdx_of_le theorem insertNth_comm (a b : α) : ∀ (i j : ℕ) (l : List α) (_ : i ≤ j) (_ : j ≤ length l), (l.insertNth i a).insertNth (j + 1) b = (l.insertNth j b).insertNth i a | 0, j, l => by simp [insertNth] | i + 1, 0, l => fun h => (Nat.not_lt_zero _ h).elim | i + 1, j + 1, [] => by simp | i + 1, j + 1, c :: l => fun h₀ h₁ => by simp only [insertNth_succ_cons, cons.injEq, true_and] exact insertNth_comm a b i j l (Nat.le_of_succ_le_succ h₀) (Nat.le_of_succ_le_succ h₁) #align list.insert_nth_comm List.insertNth_comm theorem mem_insertNth {a b : α} : ∀ {n : ℕ} {l : List α} (_ : n ≤ l.length), a ∈ l.insertNth n b ↔ a = b ∨ a ∈ l | 0, as, _ => by simp | n + 1, [], h => (Nat.not_succ_le_zero _ h).elim | n + 1, a' :: as, h => by rw [List.insertNth_succ_cons, mem_cons, mem_insertNth (Nat.le_of_succ_le_succ h), ← or_assoc, @or_comm (a = a'), or_assoc, mem_cons] #align list.mem_insert_nth List.mem_insertNth
Mathlib/Data/List/InsertNth.lean
103
112
theorem insertNth_of_length_lt (l : List α) (x : α) (n : ℕ) (h : l.length < n) : insertNth n x l = l := by
induction' l with hd tl IH generalizing n · cases n · simp at h · simp · cases n · simp at h · simp only [Nat.succ_lt_succ_iff, length] at h simpa using IH _ h
438
import Mathlib.Data.List.Basic open Function open Nat hiding one_pos assert_not_exists Set.range namespace List universe u v w variable {ι : Type*} {α : Type u} {β : Type v} {γ : Type w} {l₁ l₂ : List α} section InsertNth variable {a : α} @[simp] theorem insertNth_zero (s : List α) (x : α) : insertNth 0 x s = x :: s := rfl #align list.insert_nth_zero List.insertNth_zero @[simp] theorem insertNth_succ_nil (n : ℕ) (a : α) : insertNth (n + 1) a [] = [] := rfl #align list.insert_nth_succ_nil List.insertNth_succ_nil @[simp] theorem insertNth_succ_cons (s : List α) (hd x : α) (n : ℕ) : insertNth (n + 1) x (hd :: s) = hd :: insertNth n x s := rfl #align list.insert_nth_succ_cons List.insertNth_succ_cons theorem length_insertNth : ∀ n as, n ≤ length as → length (insertNth n a as) = length as + 1 | 0, _, _ => rfl | _ + 1, [], h => (Nat.not_succ_le_zero _ h).elim | n + 1, _ :: as, h => congr_arg Nat.succ <| length_insertNth n as (Nat.le_of_succ_le_succ h) #align list.length_insert_nth List.length_insertNth theorem eraseIdx_insertNth (n : ℕ) (l : List α) : (l.insertNth n a).eraseIdx n = l := by rw [eraseIdx_eq_modifyNthTail, insertNth, modifyNthTail_modifyNthTail_same] exact modifyNthTail_id _ _ #align list.remove_nth_insert_nth List.eraseIdx_insertNth @[deprecated (since := "2024-05-04")] alias removeNth_insertNth := eraseIdx_insertNth theorem insertNth_eraseIdx_of_ge : ∀ n m as, n < length as → n ≤ m → insertNth m a (as.eraseIdx n) = (as.insertNth (m + 1) a).eraseIdx n | 0, 0, [], has, _ => (lt_irrefl _ has).elim | 0, 0, _ :: as, _, _ => by simp [eraseIdx, insertNth] | 0, m + 1, a :: as, _, _ => rfl | n + 1, m + 1, a :: as, has, hmn => congr_arg (cons a) <| insertNth_eraseIdx_of_ge n m as (Nat.lt_of_succ_lt_succ has) (Nat.le_of_succ_le_succ hmn) #align list.insert_nth_remove_nth_of_ge List.insertNth_eraseIdx_of_ge @[deprecated (since := "2024-05-04")] alias insertNth_removeNth_of_ge := insertNth_eraseIdx_of_ge theorem insertNth_eraseIdx_of_le : ∀ n m as, n < length as → m ≤ n → insertNth m a (as.eraseIdx n) = (as.insertNth m a).eraseIdx (n + 1) | _, 0, _ :: _, _, _ => rfl | n + 1, m + 1, a :: as, has, hmn => congr_arg (cons a) <| insertNth_eraseIdx_of_le n m as (Nat.lt_of_succ_lt_succ has) (Nat.le_of_succ_le_succ hmn) #align list.insert_nth_remove_nth_of_le List.insertNth_eraseIdx_of_le @[deprecated (since := "2024-05-04")] alias insertNth_removeNth_of_le := insertNth_eraseIdx_of_le theorem insertNth_comm (a b : α) : ∀ (i j : ℕ) (l : List α) (_ : i ≤ j) (_ : j ≤ length l), (l.insertNth i a).insertNth (j + 1) b = (l.insertNth j b).insertNth i a | 0, j, l => by simp [insertNth] | i + 1, 0, l => fun h => (Nat.not_lt_zero _ h).elim | i + 1, j + 1, [] => by simp | i + 1, j + 1, c :: l => fun h₀ h₁ => by simp only [insertNth_succ_cons, cons.injEq, true_and] exact insertNth_comm a b i j l (Nat.le_of_succ_le_succ h₀) (Nat.le_of_succ_le_succ h₁) #align list.insert_nth_comm List.insertNth_comm theorem mem_insertNth {a b : α} : ∀ {n : ℕ} {l : List α} (_ : n ≤ l.length), a ∈ l.insertNth n b ↔ a = b ∨ a ∈ l | 0, as, _ => by simp | n + 1, [], h => (Nat.not_succ_le_zero _ h).elim | n + 1, a' :: as, h => by rw [List.insertNth_succ_cons, mem_cons, mem_insertNth (Nat.le_of_succ_le_succ h), ← or_assoc, @or_comm (a = a'), or_assoc, mem_cons] #align list.mem_insert_nth List.mem_insertNth theorem insertNth_of_length_lt (l : List α) (x : α) (n : ℕ) (h : l.length < n) : insertNth n x l = l := by induction' l with hd tl IH generalizing n · cases n · simp at h · simp · cases n · simp at h · simp only [Nat.succ_lt_succ_iff, length] at h simpa using IH _ h #align list.insert_nth_of_length_lt List.insertNth_of_length_lt @[simp]
Mathlib/Data/List/InsertNth.lean
116
119
theorem insertNth_length_self (l : List α) (x : α) : insertNth l.length x l = l ++ [x] := by
induction' l with hd tl IH · simp · simpa using IH
438
import Mathlib.Data.List.Basic open Function open Nat hiding one_pos assert_not_exists Set.range namespace List universe u v w variable {ι : Type*} {α : Type u} {β : Type v} {γ : Type w} {l₁ l₂ : List α} section InsertNth variable {a : α} @[simp] theorem insertNth_zero (s : List α) (x : α) : insertNth 0 x s = x :: s := rfl #align list.insert_nth_zero List.insertNth_zero @[simp] theorem insertNth_succ_nil (n : ℕ) (a : α) : insertNth (n + 1) a [] = [] := rfl #align list.insert_nth_succ_nil List.insertNth_succ_nil @[simp] theorem insertNth_succ_cons (s : List α) (hd x : α) (n : ℕ) : insertNth (n + 1) x (hd :: s) = hd :: insertNth n x s := rfl #align list.insert_nth_succ_cons List.insertNth_succ_cons theorem length_insertNth : ∀ n as, n ≤ length as → length (insertNth n a as) = length as + 1 | 0, _, _ => rfl | _ + 1, [], h => (Nat.not_succ_le_zero _ h).elim | n + 1, _ :: as, h => congr_arg Nat.succ <| length_insertNth n as (Nat.le_of_succ_le_succ h) #align list.length_insert_nth List.length_insertNth theorem eraseIdx_insertNth (n : ℕ) (l : List α) : (l.insertNth n a).eraseIdx n = l := by rw [eraseIdx_eq_modifyNthTail, insertNth, modifyNthTail_modifyNthTail_same] exact modifyNthTail_id _ _ #align list.remove_nth_insert_nth List.eraseIdx_insertNth @[deprecated (since := "2024-05-04")] alias removeNth_insertNth := eraseIdx_insertNth theorem insertNth_eraseIdx_of_ge : ∀ n m as, n < length as → n ≤ m → insertNth m a (as.eraseIdx n) = (as.insertNth (m + 1) a).eraseIdx n | 0, 0, [], has, _ => (lt_irrefl _ has).elim | 0, 0, _ :: as, _, _ => by simp [eraseIdx, insertNth] | 0, m + 1, a :: as, _, _ => rfl | n + 1, m + 1, a :: as, has, hmn => congr_arg (cons a) <| insertNth_eraseIdx_of_ge n m as (Nat.lt_of_succ_lt_succ has) (Nat.le_of_succ_le_succ hmn) #align list.insert_nth_remove_nth_of_ge List.insertNth_eraseIdx_of_ge @[deprecated (since := "2024-05-04")] alias insertNth_removeNth_of_ge := insertNth_eraseIdx_of_ge theorem insertNth_eraseIdx_of_le : ∀ n m as, n < length as → m ≤ n → insertNth m a (as.eraseIdx n) = (as.insertNth m a).eraseIdx (n + 1) | _, 0, _ :: _, _, _ => rfl | n + 1, m + 1, a :: as, has, hmn => congr_arg (cons a) <| insertNth_eraseIdx_of_le n m as (Nat.lt_of_succ_lt_succ has) (Nat.le_of_succ_le_succ hmn) #align list.insert_nth_remove_nth_of_le List.insertNth_eraseIdx_of_le @[deprecated (since := "2024-05-04")] alias insertNth_removeNth_of_le := insertNth_eraseIdx_of_le theorem insertNth_comm (a b : α) : ∀ (i j : ℕ) (l : List α) (_ : i ≤ j) (_ : j ≤ length l), (l.insertNth i a).insertNth (j + 1) b = (l.insertNth j b).insertNth i a | 0, j, l => by simp [insertNth] | i + 1, 0, l => fun h => (Nat.not_lt_zero _ h).elim | i + 1, j + 1, [] => by simp | i + 1, j + 1, c :: l => fun h₀ h₁ => by simp only [insertNth_succ_cons, cons.injEq, true_and] exact insertNth_comm a b i j l (Nat.le_of_succ_le_succ h₀) (Nat.le_of_succ_le_succ h₁) #align list.insert_nth_comm List.insertNth_comm theorem mem_insertNth {a b : α} : ∀ {n : ℕ} {l : List α} (_ : n ≤ l.length), a ∈ l.insertNth n b ↔ a = b ∨ a ∈ l | 0, as, _ => by simp | n + 1, [], h => (Nat.not_succ_le_zero _ h).elim | n + 1, a' :: as, h => by rw [List.insertNth_succ_cons, mem_cons, mem_insertNth (Nat.le_of_succ_le_succ h), ← or_assoc, @or_comm (a = a'), or_assoc, mem_cons] #align list.mem_insert_nth List.mem_insertNth theorem insertNth_of_length_lt (l : List α) (x : α) (n : ℕ) (h : l.length < n) : insertNth n x l = l := by induction' l with hd tl IH generalizing n · cases n · simp at h · simp · cases n · simp at h · simp only [Nat.succ_lt_succ_iff, length] at h simpa using IH _ h #align list.insert_nth_of_length_lt List.insertNth_of_length_lt @[simp] theorem insertNth_length_self (l : List α) (x : α) : insertNth l.length x l = l ++ [x] := by induction' l with hd tl IH · simp · simpa using IH #align list.insert_nth_length_self List.insertNth_length_self
Mathlib/Data/List/InsertNth.lean
122
127
theorem length_le_length_insertNth (l : List α) (x : α) (n : ℕ) : l.length ≤ (insertNth n x l).length := by
rcases le_or_lt n l.length with hn | hn · rw [length_insertNth _ _ hn] exact (Nat.lt_succ_self _).le · rw [insertNth_of_length_lt _ _ _ hn]
438
import Mathlib.Data.List.Basic open Function open Nat hiding one_pos assert_not_exists Set.range namespace List universe u v w variable {ι : Type*} {α : Type u} {β : Type v} {γ : Type w} {l₁ l₂ : List α} section InsertNth variable {a : α} @[simp] theorem insertNth_zero (s : List α) (x : α) : insertNth 0 x s = x :: s := rfl #align list.insert_nth_zero List.insertNth_zero @[simp] theorem insertNth_succ_nil (n : ℕ) (a : α) : insertNth (n + 1) a [] = [] := rfl #align list.insert_nth_succ_nil List.insertNth_succ_nil @[simp] theorem insertNth_succ_cons (s : List α) (hd x : α) (n : ℕ) : insertNth (n + 1) x (hd :: s) = hd :: insertNth n x s := rfl #align list.insert_nth_succ_cons List.insertNth_succ_cons theorem length_insertNth : ∀ n as, n ≤ length as → length (insertNth n a as) = length as + 1 | 0, _, _ => rfl | _ + 1, [], h => (Nat.not_succ_le_zero _ h).elim | n + 1, _ :: as, h => congr_arg Nat.succ <| length_insertNth n as (Nat.le_of_succ_le_succ h) #align list.length_insert_nth List.length_insertNth theorem eraseIdx_insertNth (n : ℕ) (l : List α) : (l.insertNth n a).eraseIdx n = l := by rw [eraseIdx_eq_modifyNthTail, insertNth, modifyNthTail_modifyNthTail_same] exact modifyNthTail_id _ _ #align list.remove_nth_insert_nth List.eraseIdx_insertNth @[deprecated (since := "2024-05-04")] alias removeNth_insertNth := eraseIdx_insertNth theorem insertNth_eraseIdx_of_ge : ∀ n m as, n < length as → n ≤ m → insertNth m a (as.eraseIdx n) = (as.insertNth (m + 1) a).eraseIdx n | 0, 0, [], has, _ => (lt_irrefl _ has).elim | 0, 0, _ :: as, _, _ => by simp [eraseIdx, insertNth] | 0, m + 1, a :: as, _, _ => rfl | n + 1, m + 1, a :: as, has, hmn => congr_arg (cons a) <| insertNth_eraseIdx_of_ge n m as (Nat.lt_of_succ_lt_succ has) (Nat.le_of_succ_le_succ hmn) #align list.insert_nth_remove_nth_of_ge List.insertNth_eraseIdx_of_ge @[deprecated (since := "2024-05-04")] alias insertNth_removeNth_of_ge := insertNth_eraseIdx_of_ge theorem insertNth_eraseIdx_of_le : ∀ n m as, n < length as → m ≤ n → insertNth m a (as.eraseIdx n) = (as.insertNth m a).eraseIdx (n + 1) | _, 0, _ :: _, _, _ => rfl | n + 1, m + 1, a :: as, has, hmn => congr_arg (cons a) <| insertNth_eraseIdx_of_le n m as (Nat.lt_of_succ_lt_succ has) (Nat.le_of_succ_le_succ hmn) #align list.insert_nth_remove_nth_of_le List.insertNth_eraseIdx_of_le @[deprecated (since := "2024-05-04")] alias insertNth_removeNth_of_le := insertNth_eraseIdx_of_le theorem insertNth_comm (a b : α) : ∀ (i j : ℕ) (l : List α) (_ : i ≤ j) (_ : j ≤ length l), (l.insertNth i a).insertNth (j + 1) b = (l.insertNth j b).insertNth i a | 0, j, l => by simp [insertNth] | i + 1, 0, l => fun h => (Nat.not_lt_zero _ h).elim | i + 1, j + 1, [] => by simp | i + 1, j + 1, c :: l => fun h₀ h₁ => by simp only [insertNth_succ_cons, cons.injEq, true_and] exact insertNth_comm a b i j l (Nat.le_of_succ_le_succ h₀) (Nat.le_of_succ_le_succ h₁) #align list.insert_nth_comm List.insertNth_comm theorem mem_insertNth {a b : α} : ∀ {n : ℕ} {l : List α} (_ : n ≤ l.length), a ∈ l.insertNth n b ↔ a = b ∨ a ∈ l | 0, as, _ => by simp | n + 1, [], h => (Nat.not_succ_le_zero _ h).elim | n + 1, a' :: as, h => by rw [List.insertNth_succ_cons, mem_cons, mem_insertNth (Nat.le_of_succ_le_succ h), ← or_assoc, @or_comm (a = a'), or_assoc, mem_cons] #align list.mem_insert_nth List.mem_insertNth theorem insertNth_of_length_lt (l : List α) (x : α) (n : ℕ) (h : l.length < n) : insertNth n x l = l := by induction' l with hd tl IH generalizing n · cases n · simp at h · simp · cases n · simp at h · simp only [Nat.succ_lt_succ_iff, length] at h simpa using IH _ h #align list.insert_nth_of_length_lt List.insertNth_of_length_lt @[simp] theorem insertNth_length_self (l : List α) (x : α) : insertNth l.length x l = l ++ [x] := by induction' l with hd tl IH · simp · simpa using IH #align list.insert_nth_length_self List.insertNth_length_self theorem length_le_length_insertNth (l : List α) (x : α) (n : ℕ) : l.length ≤ (insertNth n x l).length := by rcases le_or_lt n l.length with hn | hn · rw [length_insertNth _ _ hn] exact (Nat.lt_succ_self _).le · rw [insertNth_of_length_lt _ _ _ hn] #align list.length_le_length_insert_nth List.length_le_length_insertNth
Mathlib/Data/List/InsertNth.lean
130
135
theorem length_insertNth_le_succ (l : List α) (x : α) (n : ℕ) : (insertNth n x l).length ≤ l.length + 1 := by
rcases le_or_lt n l.length with hn | hn · rw [length_insertNth _ _ hn] · rw [insertNth_of_length_lt _ _ _ hn] exact (Nat.lt_succ_self _).le
438
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp]
Mathlib/Data/List/Join.lean
28
28
theorem join_singleton (l : List α) : [l].join = l := by
rw [join, join, append_nil]
439
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp] theorem join_singleton (l : List α) : [l].join = l := by rw [join, join, append_nil] #align list.join_singleton List.join_singleton @[simp] theorem join_eq_nil : ∀ {L : List (List α)}, join L = [] ↔ ∀ l ∈ L, l = [] | [] => iff_of_true rfl (forall_mem_nil _) | l :: L => by simp only [join, append_eq_nil, join_eq_nil, forall_mem_cons] #align list.join_eq_nil List.join_eq_nil @[simp]
Mathlib/Data/List/Join.lean
38
41
theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by
induction L₁ · rfl · simp [*]
439
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp] theorem join_singleton (l : List α) : [l].join = l := by rw [join, join, append_nil] #align list.join_singleton List.join_singleton @[simp] theorem join_eq_nil : ∀ {L : List (List α)}, join L = [] ↔ ∀ l ∈ L, l = [] | [] => iff_of_true rfl (forall_mem_nil _) | l :: L => by simp only [join, append_eq_nil, join_eq_nil, forall_mem_cons] #align list.join_eq_nil List.join_eq_nil @[simp] theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by induction L₁ · rfl · simp [*] #align list.join_append List.join_append
Mathlib/Data/List/Join.lean
44
44
theorem join_concat (L : List (List α)) (l : List α) : join (L.concat l) = join L ++ l := by
simp
439
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp] theorem join_singleton (l : List α) : [l].join = l := by rw [join, join, append_nil] #align list.join_singleton List.join_singleton @[simp] theorem join_eq_nil : ∀ {L : List (List α)}, join L = [] ↔ ∀ l ∈ L, l = [] | [] => iff_of_true rfl (forall_mem_nil _) | l :: L => by simp only [join, append_eq_nil, join_eq_nil, forall_mem_cons] #align list.join_eq_nil List.join_eq_nil @[simp] theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by induction L₁ · rfl · simp [*] #align list.join_append List.join_append theorem join_concat (L : List (List α)) (l : List α) : join (L.concat l) = join L ++ l := by simp #align list.join_concat List.join_concat @[simp] theorem join_filter_not_isEmpty : ∀ {L : List (List α)}, join (L.filter fun l => !l.isEmpty) = L.join | [] => rfl | [] :: L => by simp [join_filter_not_isEmpty (L := L), isEmpty_iff_eq_nil] | (a :: l) :: L => by simp [join_filter_not_isEmpty (L := L)] #align list.join_filter_empty_eq_ff List.join_filter_not_isEmpty @[deprecated (since := "2024-02-25")] alias join_filter_isEmpty_eq_false := join_filter_not_isEmpty @[simp]
Mathlib/Data/List/Join.lean
60
62
theorem join_filter_ne_nil [DecidablePred fun l : List α => l ≠ []] {L : List (List α)} : join (L.filter fun l => l ≠ []) = L.join := by
simp [join_filter_not_isEmpty, ← isEmpty_iff_eq_nil]
439
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp] theorem join_singleton (l : List α) : [l].join = l := by rw [join, join, append_nil] #align list.join_singleton List.join_singleton @[simp] theorem join_eq_nil : ∀ {L : List (List α)}, join L = [] ↔ ∀ l ∈ L, l = [] | [] => iff_of_true rfl (forall_mem_nil _) | l :: L => by simp only [join, append_eq_nil, join_eq_nil, forall_mem_cons] #align list.join_eq_nil List.join_eq_nil @[simp] theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by induction L₁ · rfl · simp [*] #align list.join_append List.join_append theorem join_concat (L : List (List α)) (l : List α) : join (L.concat l) = join L ++ l := by simp #align list.join_concat List.join_concat @[simp] theorem join_filter_not_isEmpty : ∀ {L : List (List α)}, join (L.filter fun l => !l.isEmpty) = L.join | [] => rfl | [] :: L => by simp [join_filter_not_isEmpty (L := L), isEmpty_iff_eq_nil] | (a :: l) :: L => by simp [join_filter_not_isEmpty (L := L)] #align list.join_filter_empty_eq_ff List.join_filter_not_isEmpty @[deprecated (since := "2024-02-25")] alias join_filter_isEmpty_eq_false := join_filter_not_isEmpty @[simp] theorem join_filter_ne_nil [DecidablePred fun l : List α => l ≠ []] {L : List (List α)} : join (L.filter fun l => l ≠ []) = L.join := by simp [join_filter_not_isEmpty, ← isEmpty_iff_eq_nil] #align list.join_filter_ne_nil List.join_filter_ne_nil
Mathlib/Data/List/Join.lean
65
66
theorem join_join (l : List (List (List α))) : l.join.join = (l.map join).join := by
induction l <;> simp [*]
439
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp] theorem join_singleton (l : List α) : [l].join = l := by rw [join, join, append_nil] #align list.join_singleton List.join_singleton @[simp] theorem join_eq_nil : ∀ {L : List (List α)}, join L = [] ↔ ∀ l ∈ L, l = [] | [] => iff_of_true rfl (forall_mem_nil _) | l :: L => by simp only [join, append_eq_nil, join_eq_nil, forall_mem_cons] #align list.join_eq_nil List.join_eq_nil @[simp] theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by induction L₁ · rfl · simp [*] #align list.join_append List.join_append theorem join_concat (L : List (List α)) (l : List α) : join (L.concat l) = join L ++ l := by simp #align list.join_concat List.join_concat @[simp] theorem join_filter_not_isEmpty : ∀ {L : List (List α)}, join (L.filter fun l => !l.isEmpty) = L.join | [] => rfl | [] :: L => by simp [join_filter_not_isEmpty (L := L), isEmpty_iff_eq_nil] | (a :: l) :: L => by simp [join_filter_not_isEmpty (L := L)] #align list.join_filter_empty_eq_ff List.join_filter_not_isEmpty @[deprecated (since := "2024-02-25")] alias join_filter_isEmpty_eq_false := join_filter_not_isEmpty @[simp] theorem join_filter_ne_nil [DecidablePred fun l : List α => l ≠ []] {L : List (List α)} : join (L.filter fun l => l ≠ []) = L.join := by simp [join_filter_not_isEmpty, ← isEmpty_iff_eq_nil] #align list.join_filter_ne_nil List.join_filter_ne_nil theorem join_join (l : List (List (List α))) : l.join.join = (l.map join).join := by induction l <;> simp [*] #align list.join_join List.join_join lemma length_join' (L : List (List α)) : length (join L) = Nat.sum (map length L) := by induction L <;> [rfl; simp only [*, join, map, Nat.sum_cons, length_append]] lemma countP_join' (p : α → Bool) : ∀ L : List (List α), countP p L.join = Nat.sum (L.map (countP p)) | [] => rfl | a :: l => by rw [join, countP_append, map_cons, Nat.sum_cons, countP_join' _ l] lemma count_join' [BEq α] (L : List (List α)) (a : α) : L.join.count a = Nat.sum (L.map (count a)) := countP_join' _ _ lemma length_bind' (l : List α) (f : α → List β) : length (l.bind f) = Nat.sum (map (length ∘ f) l) := by rw [List.bind, length_join', map_map] lemma countP_bind' (p : β → Bool) (l : List α) (f : α → List β) : countP p (l.bind f) = Nat.sum (map (countP p ∘ f) l) := by rw [List.bind, countP_join', map_map] lemma count_bind' [BEq β] (l : List α) (f : α → List β) (x : β) : count x (l.bind f) = Nat.sum (map (count x ∘ f) l) := countP_bind' _ _ _ @[simp] theorem bind_eq_nil {l : List α} {f : α → List β} : List.bind l f = [] ↔ ∀ x ∈ l, f x = [] := join_eq_nil.trans <| by simp only [mem_map, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂] #align list.bind_eq_nil List.bind_eq_nil
Mathlib/Data/List/Join.lean
105
109
theorem take_sum_join' (L : List (List α)) (i : ℕ) : L.join.take (Nat.sum ((L.map length).take i)) = (L.take i).join := by
induction L generalizing i · simp · cases i <;> simp [take_append, *]
439
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp] theorem join_singleton (l : List α) : [l].join = l := by rw [join, join, append_nil] #align list.join_singleton List.join_singleton @[simp] theorem join_eq_nil : ∀ {L : List (List α)}, join L = [] ↔ ∀ l ∈ L, l = [] | [] => iff_of_true rfl (forall_mem_nil _) | l :: L => by simp only [join, append_eq_nil, join_eq_nil, forall_mem_cons] #align list.join_eq_nil List.join_eq_nil @[simp] theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by induction L₁ · rfl · simp [*] #align list.join_append List.join_append theorem join_concat (L : List (List α)) (l : List α) : join (L.concat l) = join L ++ l := by simp #align list.join_concat List.join_concat @[simp] theorem join_filter_not_isEmpty : ∀ {L : List (List α)}, join (L.filter fun l => !l.isEmpty) = L.join | [] => rfl | [] :: L => by simp [join_filter_not_isEmpty (L := L), isEmpty_iff_eq_nil] | (a :: l) :: L => by simp [join_filter_not_isEmpty (L := L)] #align list.join_filter_empty_eq_ff List.join_filter_not_isEmpty @[deprecated (since := "2024-02-25")] alias join_filter_isEmpty_eq_false := join_filter_not_isEmpty @[simp] theorem join_filter_ne_nil [DecidablePred fun l : List α => l ≠ []] {L : List (List α)} : join (L.filter fun l => l ≠ []) = L.join := by simp [join_filter_not_isEmpty, ← isEmpty_iff_eq_nil] #align list.join_filter_ne_nil List.join_filter_ne_nil theorem join_join (l : List (List (List α))) : l.join.join = (l.map join).join := by induction l <;> simp [*] #align list.join_join List.join_join lemma length_join' (L : List (List α)) : length (join L) = Nat.sum (map length L) := by induction L <;> [rfl; simp only [*, join, map, Nat.sum_cons, length_append]] lemma countP_join' (p : α → Bool) : ∀ L : List (List α), countP p L.join = Nat.sum (L.map (countP p)) | [] => rfl | a :: l => by rw [join, countP_append, map_cons, Nat.sum_cons, countP_join' _ l] lemma count_join' [BEq α] (L : List (List α)) (a : α) : L.join.count a = Nat.sum (L.map (count a)) := countP_join' _ _ lemma length_bind' (l : List α) (f : α → List β) : length (l.bind f) = Nat.sum (map (length ∘ f) l) := by rw [List.bind, length_join', map_map] lemma countP_bind' (p : β → Bool) (l : List α) (f : α → List β) : countP p (l.bind f) = Nat.sum (map (countP p ∘ f) l) := by rw [List.bind, countP_join', map_map] lemma count_bind' [BEq β] (l : List α) (f : α → List β) (x : β) : count x (l.bind f) = Nat.sum (map (count x ∘ f) l) := countP_bind' _ _ _ @[simp] theorem bind_eq_nil {l : List α} {f : α → List β} : List.bind l f = [] ↔ ∀ x ∈ l, f x = [] := join_eq_nil.trans <| by simp only [mem_map, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂] #align list.bind_eq_nil List.bind_eq_nil theorem take_sum_join' (L : List (List α)) (i : ℕ) : L.join.take (Nat.sum ((L.map length).take i)) = (L.take i).join := by induction L generalizing i · simp · cases i <;> simp [take_append, *]
Mathlib/Data/List/Join.lean
115
119
theorem drop_sum_join' (L : List (List α)) (i : ℕ) : L.join.drop (Nat.sum ((L.map length).take i)) = (L.drop i).join := by
induction L generalizing i · simp · cases i <;> simp [drop_append, *]
439
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp] theorem join_singleton (l : List α) : [l].join = l := by rw [join, join, append_nil] #align list.join_singleton List.join_singleton @[simp] theorem join_eq_nil : ∀ {L : List (List α)}, join L = [] ↔ ∀ l ∈ L, l = [] | [] => iff_of_true rfl (forall_mem_nil _) | l :: L => by simp only [join, append_eq_nil, join_eq_nil, forall_mem_cons] #align list.join_eq_nil List.join_eq_nil @[simp] theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by induction L₁ · rfl · simp [*] #align list.join_append List.join_append theorem join_concat (L : List (List α)) (l : List α) : join (L.concat l) = join L ++ l := by simp #align list.join_concat List.join_concat @[simp] theorem join_filter_not_isEmpty : ∀ {L : List (List α)}, join (L.filter fun l => !l.isEmpty) = L.join | [] => rfl | [] :: L => by simp [join_filter_not_isEmpty (L := L), isEmpty_iff_eq_nil] | (a :: l) :: L => by simp [join_filter_not_isEmpty (L := L)] #align list.join_filter_empty_eq_ff List.join_filter_not_isEmpty @[deprecated (since := "2024-02-25")] alias join_filter_isEmpty_eq_false := join_filter_not_isEmpty @[simp] theorem join_filter_ne_nil [DecidablePred fun l : List α => l ≠ []] {L : List (List α)} : join (L.filter fun l => l ≠ []) = L.join := by simp [join_filter_not_isEmpty, ← isEmpty_iff_eq_nil] #align list.join_filter_ne_nil List.join_filter_ne_nil theorem join_join (l : List (List (List α))) : l.join.join = (l.map join).join := by induction l <;> simp [*] #align list.join_join List.join_join lemma length_join' (L : List (List α)) : length (join L) = Nat.sum (map length L) := by induction L <;> [rfl; simp only [*, join, map, Nat.sum_cons, length_append]] lemma countP_join' (p : α → Bool) : ∀ L : List (List α), countP p L.join = Nat.sum (L.map (countP p)) | [] => rfl | a :: l => by rw [join, countP_append, map_cons, Nat.sum_cons, countP_join' _ l] lemma count_join' [BEq α] (L : List (List α)) (a : α) : L.join.count a = Nat.sum (L.map (count a)) := countP_join' _ _ lemma length_bind' (l : List α) (f : α → List β) : length (l.bind f) = Nat.sum (map (length ∘ f) l) := by rw [List.bind, length_join', map_map] lemma countP_bind' (p : β → Bool) (l : List α) (f : α → List β) : countP p (l.bind f) = Nat.sum (map (countP p ∘ f) l) := by rw [List.bind, countP_join', map_map] lemma count_bind' [BEq β] (l : List α) (f : α → List β) (x : β) : count x (l.bind f) = Nat.sum (map (count x ∘ f) l) := countP_bind' _ _ _ @[simp] theorem bind_eq_nil {l : List α} {f : α → List β} : List.bind l f = [] ↔ ∀ x ∈ l, f x = [] := join_eq_nil.trans <| by simp only [mem_map, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂] #align list.bind_eq_nil List.bind_eq_nil theorem take_sum_join' (L : List (List α)) (i : ℕ) : L.join.take (Nat.sum ((L.map length).take i)) = (L.take i).join := by induction L generalizing i · simp · cases i <;> simp [take_append, *] theorem drop_sum_join' (L : List (List α)) (i : ℕ) : L.join.drop (Nat.sum ((L.map length).take i)) = (L.drop i).join := by induction L generalizing i · simp · cases i <;> simp [drop_append, *]
Mathlib/Data/List/Join.lean
123
129
theorem drop_take_succ_eq_cons_get (L : List α) (i : Fin L.length) : (L.take (i + 1)).drop i = [get L i] := by
induction' L with head tail ih · exact (Nat.not_succ_le_zero i i.isLt).elim rcases i with ⟨_ | i, hi⟩ · simp · simpa using ih ⟨i, Nat.lt_of_succ_lt_succ hi⟩
439
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp] theorem join_singleton (l : List α) : [l].join = l := by rw [join, join, append_nil] #align list.join_singleton List.join_singleton @[simp] theorem join_eq_nil : ∀ {L : List (List α)}, join L = [] ↔ ∀ l ∈ L, l = [] | [] => iff_of_true rfl (forall_mem_nil _) | l :: L => by simp only [join, append_eq_nil, join_eq_nil, forall_mem_cons] #align list.join_eq_nil List.join_eq_nil @[simp] theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by induction L₁ · rfl · simp [*] #align list.join_append List.join_append theorem join_concat (L : List (List α)) (l : List α) : join (L.concat l) = join L ++ l := by simp #align list.join_concat List.join_concat @[simp] theorem join_filter_not_isEmpty : ∀ {L : List (List α)}, join (L.filter fun l => !l.isEmpty) = L.join | [] => rfl | [] :: L => by simp [join_filter_not_isEmpty (L := L), isEmpty_iff_eq_nil] | (a :: l) :: L => by simp [join_filter_not_isEmpty (L := L)] #align list.join_filter_empty_eq_ff List.join_filter_not_isEmpty @[deprecated (since := "2024-02-25")] alias join_filter_isEmpty_eq_false := join_filter_not_isEmpty @[simp] theorem join_filter_ne_nil [DecidablePred fun l : List α => l ≠ []] {L : List (List α)} : join (L.filter fun l => l ≠ []) = L.join := by simp [join_filter_not_isEmpty, ← isEmpty_iff_eq_nil] #align list.join_filter_ne_nil List.join_filter_ne_nil theorem join_join (l : List (List (List α))) : l.join.join = (l.map join).join := by induction l <;> simp [*] #align list.join_join List.join_join lemma length_join' (L : List (List α)) : length (join L) = Nat.sum (map length L) := by induction L <;> [rfl; simp only [*, join, map, Nat.sum_cons, length_append]] lemma countP_join' (p : α → Bool) : ∀ L : List (List α), countP p L.join = Nat.sum (L.map (countP p)) | [] => rfl | a :: l => by rw [join, countP_append, map_cons, Nat.sum_cons, countP_join' _ l] lemma count_join' [BEq α] (L : List (List α)) (a : α) : L.join.count a = Nat.sum (L.map (count a)) := countP_join' _ _ lemma length_bind' (l : List α) (f : α → List β) : length (l.bind f) = Nat.sum (map (length ∘ f) l) := by rw [List.bind, length_join', map_map] lemma countP_bind' (p : β → Bool) (l : List α) (f : α → List β) : countP p (l.bind f) = Nat.sum (map (countP p ∘ f) l) := by rw [List.bind, countP_join', map_map] lemma count_bind' [BEq β] (l : List α) (f : α → List β) (x : β) : count x (l.bind f) = Nat.sum (map (count x ∘ f) l) := countP_bind' _ _ _ @[simp] theorem bind_eq_nil {l : List α} {f : α → List β} : List.bind l f = [] ↔ ∀ x ∈ l, f x = [] := join_eq_nil.trans <| by simp only [mem_map, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂] #align list.bind_eq_nil List.bind_eq_nil theorem take_sum_join' (L : List (List α)) (i : ℕ) : L.join.take (Nat.sum ((L.map length).take i)) = (L.take i).join := by induction L generalizing i · simp · cases i <;> simp [take_append, *] theorem drop_sum_join' (L : List (List α)) (i : ℕ) : L.join.drop (Nat.sum ((L.map length).take i)) = (L.drop i).join := by induction L generalizing i · simp · cases i <;> simp [drop_append, *] theorem drop_take_succ_eq_cons_get (L : List α) (i : Fin L.length) : (L.take (i + 1)).drop i = [get L i] := by induction' L with head tail ih · exact (Nat.not_succ_le_zero i i.isLt).elim rcases i with ⟨_ | i, hi⟩ · simp · simpa using ih ⟨i, Nat.lt_of_succ_lt_succ hi⟩ set_option linter.deprecated false in @[deprecated drop_take_succ_eq_cons_get (since := "2023-01-10")]
Mathlib/Data/List/Join.lean
135
145
theorem drop_take_succ_eq_cons_nthLe (L : List α) {i : ℕ} (hi : i < L.length) : (L.take (i + 1)).drop i = [nthLe L i hi] := by
induction' L with head tail generalizing i · simp only [length] at hi exact (Nat.not_succ_le_zero i hi).elim cases' i with i hi · simp rfl have : i < tail.length := by simpa using hi simp [*] rfl
439
import Mathlib.Data.List.Basic #align_import data.list.join from "leanprover-community/mathlib"@"18a5306c091183ac90884daa9373fa3b178e8607" -- Make sure we don't import algebra assert_not_exists Monoid variable {α β : Type*} namespace List attribute [simp] join -- Porting note (#10618): simp can prove this -- @[simp] theorem join_singleton (l : List α) : [l].join = l := by rw [join, join, append_nil] #align list.join_singleton List.join_singleton @[simp] theorem join_eq_nil : ∀ {L : List (List α)}, join L = [] ↔ ∀ l ∈ L, l = [] | [] => iff_of_true rfl (forall_mem_nil _) | l :: L => by simp only [join, append_eq_nil, join_eq_nil, forall_mem_cons] #align list.join_eq_nil List.join_eq_nil @[simp] theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by induction L₁ · rfl · simp [*] #align list.join_append List.join_append theorem join_concat (L : List (List α)) (l : List α) : join (L.concat l) = join L ++ l := by simp #align list.join_concat List.join_concat @[simp] theorem join_filter_not_isEmpty : ∀ {L : List (List α)}, join (L.filter fun l => !l.isEmpty) = L.join | [] => rfl | [] :: L => by simp [join_filter_not_isEmpty (L := L), isEmpty_iff_eq_nil] | (a :: l) :: L => by simp [join_filter_not_isEmpty (L := L)] #align list.join_filter_empty_eq_ff List.join_filter_not_isEmpty @[deprecated (since := "2024-02-25")] alias join_filter_isEmpty_eq_false := join_filter_not_isEmpty @[simp] theorem join_filter_ne_nil [DecidablePred fun l : List α => l ≠ []] {L : List (List α)} : join (L.filter fun l => l ≠ []) = L.join := by simp [join_filter_not_isEmpty, ← isEmpty_iff_eq_nil] #align list.join_filter_ne_nil List.join_filter_ne_nil theorem join_join (l : List (List (List α))) : l.join.join = (l.map join).join := by induction l <;> simp [*] #align list.join_join List.join_join lemma length_join' (L : List (List α)) : length (join L) = Nat.sum (map length L) := by induction L <;> [rfl; simp only [*, join, map, Nat.sum_cons, length_append]] lemma countP_join' (p : α → Bool) : ∀ L : List (List α), countP p L.join = Nat.sum (L.map (countP p)) | [] => rfl | a :: l => by rw [join, countP_append, map_cons, Nat.sum_cons, countP_join' _ l] lemma count_join' [BEq α] (L : List (List α)) (a : α) : L.join.count a = Nat.sum (L.map (count a)) := countP_join' _ _ lemma length_bind' (l : List α) (f : α → List β) : length (l.bind f) = Nat.sum (map (length ∘ f) l) := by rw [List.bind, length_join', map_map] lemma countP_bind' (p : β → Bool) (l : List α) (f : α → List β) : countP p (l.bind f) = Nat.sum (map (countP p ∘ f) l) := by rw [List.bind, countP_join', map_map] lemma count_bind' [BEq β] (l : List α) (f : α → List β) (x : β) : count x (l.bind f) = Nat.sum (map (count x ∘ f) l) := countP_bind' _ _ _ @[simp] theorem bind_eq_nil {l : List α} {f : α → List β} : List.bind l f = [] ↔ ∀ x ∈ l, f x = [] := join_eq_nil.trans <| by simp only [mem_map, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂] #align list.bind_eq_nil List.bind_eq_nil theorem take_sum_join' (L : List (List α)) (i : ℕ) : L.join.take (Nat.sum ((L.map length).take i)) = (L.take i).join := by induction L generalizing i · simp · cases i <;> simp [take_append, *] theorem drop_sum_join' (L : List (List α)) (i : ℕ) : L.join.drop (Nat.sum ((L.map length).take i)) = (L.drop i).join := by induction L generalizing i · simp · cases i <;> simp [drop_append, *] theorem drop_take_succ_eq_cons_get (L : List α) (i : Fin L.length) : (L.take (i + 1)).drop i = [get L i] := by induction' L with head tail ih · exact (Nat.not_succ_le_zero i i.isLt).elim rcases i with ⟨_ | i, hi⟩ · simp · simpa using ih ⟨i, Nat.lt_of_succ_lt_succ hi⟩ set_option linter.deprecated false in @[deprecated drop_take_succ_eq_cons_get (since := "2023-01-10")] theorem drop_take_succ_eq_cons_nthLe (L : List α) {i : ℕ} (hi : i < L.length) : (L.take (i + 1)).drop i = [nthLe L i hi] := by induction' L with head tail generalizing i · simp only [length] at hi exact (Nat.not_succ_le_zero i hi).elim cases' i with i hi · simp rfl have : i < tail.length := by simpa using hi simp [*] rfl #align list.drop_take_succ_eq_cons_nth_le List.drop_take_succ_eq_cons_nthLe
Mathlib/Data/List/Join.lean
153
159
theorem drop_take_succ_join_eq_get' (L : List (List α)) (i : Fin L.length) : (L.join.take (Nat.sum ((L.map length).take (i + 1)))).drop (Nat.sum ((L.map length).take i)) = get L i := by
have : (L.map length).take i = ((L.take (i + 1)).map length).take i := by simp [map_take, take_take, Nat.min_eq_left] simp only [this, length_map, take_sum_join', drop_sum_join', drop_take_succ_eq_cons_get, join, append_nil]
439
import Mathlib.Data.List.Join #align_import data.list.permutation from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" -- Make sure we don't import algebra assert_not_exists Monoid open Nat variable {α β : Type*} namespace List theorem permutationsAux2_fst (t : α) (ts : List α) (r : List β) : ∀ (ys : List α) (f : List α → β), (permutationsAux2 t ts r ys f).1 = ys ++ ts | [], f => rfl | y :: ys, f => by simp [permutationsAux2, permutationsAux2_fst t _ _ ys] #align list.permutations_aux2_fst List.permutationsAux2_fst @[simp] theorem permutationsAux2_snd_nil (t : α) (ts : List α) (r : List β) (f : List α → β) : (permutationsAux2 t ts r [] f).2 = r := rfl #align list.permutations_aux2_snd_nil List.permutationsAux2_snd_nil @[simp]
Mathlib/Data/List/Permutation.lean
69
73
theorem permutationsAux2_snd_cons (t : α) (ts : List α) (r : List β) (y : α) (ys : List α) (f : List α → β) : (permutationsAux2 t ts r (y :: ys) f).2 = f (t :: y :: ys ++ ts) :: (permutationsAux2 t ts r ys fun x : List α => f (y :: x)).2 := by
simp [permutationsAux2, permutationsAux2_fst t _ _ ys]
440
import Mathlib.Data.List.Join #align_import data.list.permutation from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" -- Make sure we don't import algebra assert_not_exists Monoid open Nat variable {α β : Type*} namespace List theorem permutationsAux2_fst (t : α) (ts : List α) (r : List β) : ∀ (ys : List α) (f : List α → β), (permutationsAux2 t ts r ys f).1 = ys ++ ts | [], f => rfl | y :: ys, f => by simp [permutationsAux2, permutationsAux2_fst t _ _ ys] #align list.permutations_aux2_fst List.permutationsAux2_fst @[simp] theorem permutationsAux2_snd_nil (t : α) (ts : List α) (r : List β) (f : List α → β) : (permutationsAux2 t ts r [] f).2 = r := rfl #align list.permutations_aux2_snd_nil List.permutationsAux2_snd_nil @[simp] theorem permutationsAux2_snd_cons (t : α) (ts : List α) (r : List β) (y : α) (ys : List α) (f : List α → β) : (permutationsAux2 t ts r (y :: ys) f).2 = f (t :: y :: ys ++ ts) :: (permutationsAux2 t ts r ys fun x : List α => f (y :: x)).2 := by simp [permutationsAux2, permutationsAux2_fst t _ _ ys] #align list.permutations_aux2_snd_cons List.permutationsAux2_snd_cons
Mathlib/Data/List/Permutation.lean
77
79
theorem permutationsAux2_append (t : α) (ts : List α) (r : List β) (ys : List α) (f : List α → β) : (permutationsAux2 t ts nil ys f).2 ++ r = (permutationsAux2 t ts r ys f).2 := by
induction ys generalizing f <;> simp [*]
440
import Mathlib.Data.List.Join #align_import data.list.permutation from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" -- Make sure we don't import algebra assert_not_exists Monoid open Nat variable {α β : Type*} namespace List theorem permutationsAux2_fst (t : α) (ts : List α) (r : List β) : ∀ (ys : List α) (f : List α → β), (permutationsAux2 t ts r ys f).1 = ys ++ ts | [], f => rfl | y :: ys, f => by simp [permutationsAux2, permutationsAux2_fst t _ _ ys] #align list.permutations_aux2_fst List.permutationsAux2_fst @[simp] theorem permutationsAux2_snd_nil (t : α) (ts : List α) (r : List β) (f : List α → β) : (permutationsAux2 t ts r [] f).2 = r := rfl #align list.permutations_aux2_snd_nil List.permutationsAux2_snd_nil @[simp] theorem permutationsAux2_snd_cons (t : α) (ts : List α) (r : List β) (y : α) (ys : List α) (f : List α → β) : (permutationsAux2 t ts r (y :: ys) f).2 = f (t :: y :: ys ++ ts) :: (permutationsAux2 t ts r ys fun x : List α => f (y :: x)).2 := by simp [permutationsAux2, permutationsAux2_fst t _ _ ys] #align list.permutations_aux2_snd_cons List.permutationsAux2_snd_cons theorem permutationsAux2_append (t : α) (ts : List α) (r : List β) (ys : List α) (f : List α → β) : (permutationsAux2 t ts nil ys f).2 ++ r = (permutationsAux2 t ts r ys f).2 := by induction ys generalizing f <;> simp [*] #align list.permutations_aux2_append List.permutationsAux2_append
Mathlib/Data/List/Permutation.lean
83
87
theorem permutationsAux2_comp_append {t : α} {ts ys : List α} {r : List β} (f : List α → β) : ((permutationsAux2 t [] r ys) fun x => f (x ++ ts)).2 = (permutationsAux2 t ts r ys f).2 := by
induction' ys with ys_hd _ ys_ih generalizing f · simp · simp [ys_ih fun xs => f (ys_hd :: xs)]
440
import Mathlib.Data.List.Join #align_import data.list.permutation from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" -- Make sure we don't import algebra assert_not_exists Monoid open Nat variable {α β : Type*} namespace List theorem permutationsAux2_fst (t : α) (ts : List α) (r : List β) : ∀ (ys : List α) (f : List α → β), (permutationsAux2 t ts r ys f).1 = ys ++ ts | [], f => rfl | y :: ys, f => by simp [permutationsAux2, permutationsAux2_fst t _ _ ys] #align list.permutations_aux2_fst List.permutationsAux2_fst @[simp] theorem permutationsAux2_snd_nil (t : α) (ts : List α) (r : List β) (f : List α → β) : (permutationsAux2 t ts r [] f).2 = r := rfl #align list.permutations_aux2_snd_nil List.permutationsAux2_snd_nil @[simp] theorem permutationsAux2_snd_cons (t : α) (ts : List α) (r : List β) (y : α) (ys : List α) (f : List α → β) : (permutationsAux2 t ts r (y :: ys) f).2 = f (t :: y :: ys ++ ts) :: (permutationsAux2 t ts r ys fun x : List α => f (y :: x)).2 := by simp [permutationsAux2, permutationsAux2_fst t _ _ ys] #align list.permutations_aux2_snd_cons List.permutationsAux2_snd_cons theorem permutationsAux2_append (t : α) (ts : List α) (r : List β) (ys : List α) (f : List α → β) : (permutationsAux2 t ts nil ys f).2 ++ r = (permutationsAux2 t ts r ys f).2 := by induction ys generalizing f <;> simp [*] #align list.permutations_aux2_append List.permutationsAux2_append theorem permutationsAux2_comp_append {t : α} {ts ys : List α} {r : List β} (f : List α → β) : ((permutationsAux2 t [] r ys) fun x => f (x ++ ts)).2 = (permutationsAux2 t ts r ys f).2 := by induction' ys with ys_hd _ ys_ih generalizing f · simp · simp [ys_ih fun xs => f (ys_hd :: xs)] #align list.permutations_aux2_comp_append List.permutationsAux2_comp_append
Mathlib/Data/List/Permutation.lean
90
100
theorem map_permutationsAux2' {α' β'} (g : α → α') (g' : β → β') (t : α) (ts ys : List α) (r : List β) (f : List α → β) (f' : List α' → β') (H : ∀ a, g' (f a) = f' (map g a)) : map g' (permutationsAux2 t ts r ys f).2 = (permutationsAux2 (g t) (map g ts) (map g' r) (map g ys) f').2 := by
induction' ys with ys_hd _ ys_ih generalizing f f' · simp · simp only [map, permutationsAux2_snd_cons, cons_append, cons.injEq] rw [ys_ih, permutationsAux2_fst] · refine ⟨?_, rfl⟩ simp only [← map_cons, ← map_append]; apply H · intro a; apply H
440
import Mathlib.Data.List.Join #align_import data.list.permutation from "leanprover-community/mathlib"@"dd71334db81d0bd444af1ee339a29298bef40734" -- Make sure we don't import algebra assert_not_exists Monoid open Nat variable {α β : Type*} namespace List theorem permutationsAux2_fst (t : α) (ts : List α) (r : List β) : ∀ (ys : List α) (f : List α → β), (permutationsAux2 t ts r ys f).1 = ys ++ ts | [], f => rfl | y :: ys, f => by simp [permutationsAux2, permutationsAux2_fst t _ _ ys] #align list.permutations_aux2_fst List.permutationsAux2_fst @[simp] theorem permutationsAux2_snd_nil (t : α) (ts : List α) (r : List β) (f : List α → β) : (permutationsAux2 t ts r [] f).2 = r := rfl #align list.permutations_aux2_snd_nil List.permutationsAux2_snd_nil @[simp] theorem permutationsAux2_snd_cons (t : α) (ts : List α) (r : List β) (y : α) (ys : List α) (f : List α → β) : (permutationsAux2 t ts r (y :: ys) f).2 = f (t :: y :: ys ++ ts) :: (permutationsAux2 t ts r ys fun x : List α => f (y :: x)).2 := by simp [permutationsAux2, permutationsAux2_fst t _ _ ys] #align list.permutations_aux2_snd_cons List.permutationsAux2_snd_cons theorem permutationsAux2_append (t : α) (ts : List α) (r : List β) (ys : List α) (f : List α → β) : (permutationsAux2 t ts nil ys f).2 ++ r = (permutationsAux2 t ts r ys f).2 := by induction ys generalizing f <;> simp [*] #align list.permutations_aux2_append List.permutationsAux2_append theorem permutationsAux2_comp_append {t : α} {ts ys : List α} {r : List β} (f : List α → β) : ((permutationsAux2 t [] r ys) fun x => f (x ++ ts)).2 = (permutationsAux2 t ts r ys f).2 := by induction' ys with ys_hd _ ys_ih generalizing f · simp · simp [ys_ih fun xs => f (ys_hd :: xs)] #align list.permutations_aux2_comp_append List.permutationsAux2_comp_append theorem map_permutationsAux2' {α' β'} (g : α → α') (g' : β → β') (t : α) (ts ys : List α) (r : List β) (f : List α → β) (f' : List α' → β') (H : ∀ a, g' (f a) = f' (map g a)) : map g' (permutationsAux2 t ts r ys f).2 = (permutationsAux2 (g t) (map g ts) (map g' r) (map g ys) f').2 := by induction' ys with ys_hd _ ys_ih generalizing f f' · simp · simp only [map, permutationsAux2_snd_cons, cons_append, cons.injEq] rw [ys_ih, permutationsAux2_fst] · refine ⟨?_, rfl⟩ simp only [← map_cons, ← map_append]; apply H · intro a; apply H #align list.map_permutations_aux2' List.map_permutationsAux2'
Mathlib/Data/List/Permutation.lean
104
108
theorem map_permutationsAux2 (t : α) (ts : List α) (ys : List α) (f : List α → β) : (permutationsAux2 t ts [] ys id).2.map f = (permutationsAux2 t ts [] ys f).2 := by
rw [map_permutationsAux2' id, map_id, map_id] · rfl simp
440