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HasProd.mul_disjoint {s t : Set β} (hs : Disjoint s t) (ha : HasProd (f ∘ (↑) : s → α) a) (hb : HasProd (f ∘ (↑) : t → α) b) : HasProd (f ∘ (↑) : (s ∪ t : Set β) → α) (a * b) := by rw [hasProd_subtype_iff_mulIndicator] at * rw [Set.mulIndicator_union_of_disjoint hs] exact ha.mul hb @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
HasProd.mul_disjoint
null
hasProd_prod_disjoint {ι} (s : Finset ι) {t : ι → Set β} {a : ι → α} (hs : (s : Set ι).Pairwise (Disjoint on t)) (hf : ∀ i ∈ s, HasProd (f ∘ (↑) : t i → α) (a i)) : HasProd (f ∘ (↑) : (⋃ i ∈ s, t i) → α) (∏ i ∈ s, a i) := by simp_rw [hasProd_subtype_iff_mulIndicator] at * rw [Finset.mulIndicator_biUnion _ _ hs] exact hasProd_prod hf @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
hasProd_prod_disjoint
null
HasProd.mul_isCompl {s t : Set β} (hs : IsCompl s t) (ha : HasProd (f ∘ (↑) : s → α) a) (hb : HasProd (f ∘ (↑) : t → α) b) : HasProd f (a * b) := by simpa [← hs.compl_eq] using (hasProd_subtype_iff_mulIndicator.1 ha).mul (hasProd_subtype_iff_mulIndicator.1 hb) @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
HasProd.mul_isCompl
null
HasProd.mul_compl {s : Set β} (ha : HasProd (f ∘ (↑) : s → α) a) (hb : HasProd (f ∘ (↑) : (sᶜ : Set β) → α) b) : HasProd f (a * b) := ha.mul_isCompl isCompl_compl hb @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
HasProd.mul_compl
null
Multipliable.mul_compl {s : Set β} (hs : Multipliable (f ∘ (↑) : s → α)) (hsc : Multipliable (f ∘ (↑) : (sᶜ : Set β) → α)) : Multipliable f := (hs.hasProd.mul_compl hsc.hasProd).multipliable @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Multipliable.mul_compl
null
HasProd.compl_mul {s : Set β} (ha : HasProd (f ∘ (↑) : (sᶜ : Set β) → α) a) (hb : HasProd (f ∘ (↑) : s → α) b) : HasProd f (a * b) := ha.mul_isCompl isCompl_compl.symm hb @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
HasProd.compl_mul
null
Multipliable.compl_add {s : Set β} (hs : Multipliable (f ∘ (↑) : (sᶜ : Set β) → α)) (hsc : Multipliable (f ∘ (↑) : s → α)) : Multipliable f := (hs.hasProd.compl_mul hsc.hasProd).multipliable
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Multipliable.compl_add
null
@[to_additive /-- Version of `HasSum.update` for `AddCommMonoid` rather than `AddCommGroup`. Rather than showing that `f.update` has a specific sum in terms of `HasSum`, it gives a relationship between the sums of `f` and `f.update` given that both exist. -/] HasProd.update' {α β : Type*} [TopologicalSpace α] [CommMonoid α] [T2Space α] [ContinuousMul α] [DecidableEq β] {f : β → α} {a a' : α} (hf : HasProd f a) (b : β) (x : α) (hf' : HasProd (update f b x) a') : a * x = a' * f b := by have : ∀ b', f b' * ite (b' = b) x 1 = update f b x b' * ite (b' = b) (f b) 1 := by intro b' split_ifs with hb' · simpa only [Function.update_apply, hb', eq_self_iff_true] using mul_comm (f b) x · simp only [Function.update_apply, hb', if_false] have h := hf.mul (hasProd_ite_eq b x) simp_rw [this] at h exact HasProd.unique h (hf'.mul (hasProd_ite_eq b (f b)))
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
HasProd.update'
Version of `HasProd.update` for `CommMonoid` rather than `CommGroup`. Rather than showing that `f.update` has a specific product in terms of `HasProd`, it gives a relationship between the products of `f` and `f.update` given that both exist.
@[to_additive /-- Version of `hasSum_ite_sub_hasSum` for `AddCommMonoid` rather than `AddCommGroup`. Rather than showing that the `ite` expression has a specific sum in terms of `HasSum`, it gives a relationship between the sums of `f` and `ite (n = b) 0 (f n)` given that both exist. -/] eq_mul_of_hasProd_ite {α β : Type*} [TopologicalSpace α] [CommMonoid α] [T2Space α] [ContinuousMul α] [DecidableEq β] {f : β → α} {a : α} (hf : HasProd f a) (b : β) (a' : α) (hf' : HasProd (fun n ↦ ite (n = b) 1 (f n)) a') : a = a' * f b := by refine (mul_one a).symm.trans (hf.update' b 1 ?_) convert hf' apply update_apply
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
eq_mul_of_hasProd_ite
Version of `hasProd_ite_div_hasProd` for `CommMonoid` rather than `CommGroup`. Rather than showing that the `ite` expression has a specific product in terms of `HasProd`, it gives a relationship between the products of `f` and `ite (n = b) 0 (f n)` given that both exist.
@[to_additive] tprod_congr_set_coe (f : β → α) {s t : Set β} (h : s = t) : ∏' x : s, f x = ∏' x : t, f x := by rw [h] @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_congr_set_coe
null
tprod_congr_subtype (f : β → α) {P Q : β → Prop} (h : ∀ x, P x ↔ Q x) : ∏' x : {x // P x}, f x = ∏' x : {x // Q x}, f x := tprod_congr_set_coe f <| Set.ext h @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_congr_subtype
null
tprod_eq_finprod (hf : (mulSupport f).Finite) : ∏' b, f b = ∏ᶠ b, f b := by simp [tprod_def, multipliable_of_finite_mulSupport hf, hf] @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_eq_finprod
null
tprod_eq_prod' {s : Finset β} (hf : mulSupport f ⊆ s) : ∏' b, f b = ∏ b ∈ s, f b := by rw [tprod_eq_finprod (s.finite_toSet.subset hf), finprod_eq_prod_of_mulSupport_subset _ hf] @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_eq_prod'
null
tprod_eq_prod {s : Finset β} (hf : ∀ b ∉ s, f b = 1) : ∏' b, f b = ∏ b ∈ s, f b := tprod_eq_prod' <| mulSupport_subset_iff'.2 hf @[to_additive (attr := simp)]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_eq_prod
null
tprod_one : ∏' _ : β, (1 : α) = 1 := by rw [tprod_eq_finprod] <;> simp @[to_additive (attr := simp)]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_one
null
tprod_empty [IsEmpty β] : ∏' b, f b = 1 := by rw [tprod_eq_prod (s := (∅ : Finset β))] <;> simp @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_empty
null
tprod_congr {f g : β → α} (hfg : ∀ b, f b = g b) : ∏' b, f b = ∏' b, g b := congr_arg tprod (funext hfg) @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_congr
null
tprod_congr₂ {f g : γ → β → α} (hfg : ∀ b c, f b c = g b c) : ∏' c, ∏' b, f b c = ∏' c, ∏' b, g b c := tprod_congr fun c ↦ tprod_congr fun b ↦ hfg b c @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_congr₂
null
tprod_fintype [Fintype β] (f : β → α) : ∏' b, f b = ∏ b, f b := by apply tprod_eq_prod; simp @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_fintype
null
prod_eq_tprod_mulIndicator (f : β → α) (s : Finset β) : ∏ x ∈ s, f x = ∏' x, Set.mulIndicator (↑s) f x := by rw [tprod_eq_prod' (Set.mulSupport_mulIndicator_subset), Finset.prod_mulIndicator_subset _ Finset.Subset.rfl] @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
prod_eq_tprod_mulIndicator
null
tprod_bool (f : Bool → α) : ∏' i : Bool, f i = f false * f true := by rw [tprod_fintype, Fintype.prod_bool, mul_comm] @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_bool
null
tprod_eq_mulSingle {f : β → α} (b : β) (hf : ∀ b' ≠ b, f b' = 1) : ∏' b, f b = f b := by rw [tprod_eq_prod (s := {b}), prod_singleton] exact fun b' hb' ↦ hf b' (by simpa using hb') @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_eq_mulSingle
null
tprod_tprod_eq_mulSingle (f : β → γ → α) (b : β) (c : γ) (hfb : ∀ b' ≠ b, f b' c = 1) (hfc : ∀ b', ∀ c' ≠ c, f b' c' = 1) : ∏' (b') (c'), f b' c' = f b c := calc ∏' (b') (c'), f b' c' = ∏' b', f b' c := tprod_congr fun b' ↦ tprod_eq_mulSingle _ (hfc b') _ = f b c := tprod_eq_mulSingle _ hfb @[to_additive (attr := simp)]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_tprod_eq_mulSingle
null
tprod_ite_eq (b : β) [DecidablePred (· = b)] (a : α) : ∏' b', (if b' = b then a else 1) = a := by rw [tprod_eq_mulSingle b] · simp · intro b' hb'; simp [hb'] @[to_additive (attr := simp)]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_ite_eq
null
Finset.tprod_subtype (s : Finset β) (f : β → α) : ∏' x : { x // x ∈ s }, f x = ∏ x ∈ s, f x := by rw [← prod_attach]; exact tprod_fintype _ @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Finset.tprod_subtype
null
Finset.tprod_subtype' (s : Finset β) (f : β → α) : ∏' x : (s : Set β), f x = ∏ x ∈ s, f x := by simp @[to_additive (attr := simp)]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Finset.tprod_subtype'
null
tprod_singleton (b : β) (f : β → α) : ∏' x : ({b} : Set β), f x = f b := by rw [← coe_singleton, Finset.tprod_subtype', prod_singleton] open scoped Classical in @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_singleton
null
Function.Injective.tprod_eq {g : γ → β} (hg : Injective g) {f : β → α} (hf : mulSupport f ⊆ Set.range g) : ∏' c, f (g c) = ∏' b, f b := by have : mulSupport f = g '' mulSupport (f ∘ g) := by rw [mulSupport_comp_eq_preimage, Set.image_preimage_eq_iff.2 hf] rw [← Function.comp_def] by_cases hf_fin : (mulSupport f).Finite · have hfg_fin : (mulSupport (f ∘ g)).Finite := hf_fin.preimage hg.injOn lift g to γ ↪ β using hg simp_rw [tprod_eq_prod' hf_fin.coe_toFinset.ge, tprod_eq_prod' hfg_fin.coe_toFinset.ge, comp_apply, ← Finset.prod_map] refine Finset.prod_congr (Finset.coe_injective ?_) fun _ _ ↦ rfl simp [this] · have hf_fin' : ¬ Set.Finite (mulSupport (f ∘ g)) := by rwa [this, Set.finite_image_iff hg.injOn] at hf_fin simp_rw [tprod_def, if_neg hf_fin, if_neg hf_fin', Multipliable, funext fun a => propext <| hg.hasProd_iff (mulSupport_subset_iff'.1 hf) (a := a)] @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Function.Injective.tprod_eq
null
Equiv.tprod_eq (e : γ ≃ β) (f : β → α) : ∏' c, f (e c) = ∏' b, f b := e.injective.tprod_eq <| by simp @[to_additive (attr := simp)]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Equiv.tprod_eq
null
tprod_comp_neg {β : Type*} [InvolutiveNeg β] (f : β → α) : ∏' d, f (-d) = ∏' d, f d := (Equiv.neg β).tprod_eq f /-! ### `tprod` on subsets - part 1 -/ @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_comp_neg
null
tprod_subtype_eq_of_mulSupport_subset {f : β → α} {s : Set β} (hs : mulSupport f ⊆ s) : ∏' x : s, f x = ∏' x, f x := Subtype.val_injective.tprod_eq <| by simpa @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_subtype_eq_of_mulSupport_subset
null
tprod_subtype_mulSupport (f : β → α) : ∏' x : mulSupport f, f x = ∏' x, f x := tprod_subtype_eq_of_mulSupport_subset Set.Subset.rfl @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_subtype_mulSupport
null
tprod_subtype (s : Set β) (f : β → α) : ∏' x : s, f x = ∏' x, s.mulIndicator f x := by rw [← tprod_subtype_eq_of_mulSupport_subset Set.mulSupport_mulIndicator_subset, tprod_congr] simp @[to_additive (attr := simp)]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_subtype
null
tprod_univ (f : β → α) : ∏' x : (Set.univ : Set β), f x = ∏' x, f x := tprod_subtype_eq_of_mulSupport_subset <| Set.subset_univ _ @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_univ
null
tprod_image {g : γ → β} (f : β → α) {s : Set γ} (hg : Set.InjOn g s) : ∏' x : g '' s, f x = ∏' x : s, f (g x) := ((Equiv.Set.imageOfInjOn _ _ hg).tprod_eq fun x ↦ f x).symm @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_image
null
tprod_range {g : γ → β} (f : β → α) (hg : Injective g) : ∏' x : Set.range g, f x = ∏' x, f (g x) := by rw [← Set.image_univ, tprod_image f hg.injOn] simp_rw [← comp_apply (g := g), tprod_univ (f ∘ g)]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_range
null
@[to_additive /-- If `f b = 0` for all `b ∈ t`, then the sum of `f a` with `a ∈ s` is the same as the sum of `f a` with `a ∈ s ∖ t`. -/] tprod_setElem_eq_tprod_setElem_diff {f : β → α} (s t : Set β) (hf₀ : ∀ b ∈ t, f b = 1) : ∏' a : s, f a = ∏' a : (s \ t : Set β), f a := .symm <| (Set.inclusion_injective (t := s) Set.diff_subset).tprod_eq (f := f ∘ (↑)) <| mulSupport_subset_iff'.2 fun b hb ↦ hf₀ b <| by simpa using hb
lemma
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_setElem_eq_tprod_setElem_diff
If `f b = 1` for all `b ∈ t`, then the product of `f a` with `a ∈ s` is the same as the product of `f a` with `a ∈ s ∖ t`.
@[to_additive /-- If `f b = 0`, then the sum of `f a` with `a ∈ s` is the same as the sum of `f a` for `a ∈ s ∖ {b}`. -/] tprod_eq_tprod_diff_singleton {f : β → α} (s : Set β) {b : β} (hf₀ : f b = 1) : ∏' a : s, f a = ∏' a : (s \ {b} : Set β), f a := tprod_setElem_eq_tprod_setElem_diff s {b} fun _ ha ↦ ha ▸ hf₀ @[to_additive]
lemma
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_eq_tprod_diff_singleton
If `f b = 1`, then the product of `f a` with `a ∈ s` is the same as the product of `f a` for `a ∈ s ∖ {b}`.
tprod_eq_tprod_of_ne_one_bij {g : γ → α} (i : mulSupport g → β) (hi : Injective i) (hf : mulSupport f ⊆ Set.range i) (hfg : ∀ x, f (i x) = g x) : ∏' x, f x = ∏' y, g y := by rw [← tprod_subtype_mulSupport g, ← hi.tprod_eq hf] simp only [hfg] @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_eq_tprod_of_ne_one_bij
null
Equiv.tprod_eq_tprod_of_mulSupport {f : β → α} {g : γ → α} (e : mulSupport f ≃ mulSupport g) (he : ∀ x, g (e x) = f x) : ∏' x, f x = ∏' y, g y := .symm <| tprod_eq_tprod_of_ne_one_bij _ (Subtype.val_injective.comp e.injective) (by simp) he @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Equiv.tprod_eq_tprod_of_mulSupport
null
tprod_dite_right (P : Prop) [Decidable P] (x : β → ¬P → α) : ∏' b : β, (if h : P then (1 : α) else x b h) = if h : P then (1 : α) else ∏' b : β, x b h := by by_cases hP : P <;> simp [hP] @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_dite_right
null
tprod_dite_left (P : Prop) [Decidable P] (x : β → P → α) : ∏' b : β, (if h : P then x b h else 1) = if h : P then ∏' b : β, x b h else 1 := by by_cases hP : P <;> simp [hP] @[to_additive (attr := simp)]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_dite_left
null
tprod_extend_one {γ : Type*} {g : γ → β} (hg : Injective g) (f : γ → α) : ∏' y, extend g f 1 y = ∏' x, f x := by have : mulSupport (extend g f 1) ⊆ Set.range g := mulSupport_subset_iff'.2 <| extend_apply' _ _ simp_rw [← hg.tprod_eq this, hg.extend_apply] variable [T2Space α] @[to_additive]
lemma
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_extend_one
null
Function.Surjective.tprod_eq_tprod_of_hasProd_iff_hasProd {α' : Type*} [CommMonoid α'] [TopologicalSpace α'] {e : α' → α} (hes : Function.Surjective e) (h1 : e 1 = 1) {f : β → α} {g : γ → α'} (h : ∀ {a}, HasProd f (e a) ↔ HasProd g a) : ∏' b, f b = e (∏' c, g c) := by_cases (fun x ↦ (h.mpr x.hasProd).tprod_eq) fun hg : ¬Multipliable g ↦ by have hf : ¬Multipliable f := mt (hes.multipliable_iff_of_hasProd_iff @h).1 hg simp [tprod_def, hf, hg, h1] @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Function.Surjective.tprod_eq_tprod_of_hasProd_iff_hasProd
null
tprod_eq_tprod_of_hasProd_iff_hasProd {f : β → α} {g : γ → α} (h : ∀ {a}, HasProd f a ↔ HasProd g a) : ∏' b, f b = ∏' c, g c := surjective_id.tprod_eq_tprod_of_hasProd_iff_hasProd rfl @h
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_eq_tprod_of_hasProd_iff_hasProd
null
@[to_additive] protected Multipliable.tprod_mul (hf : Multipliable f) (hg : Multipliable g) : ∏' b, (f b * g b) = (∏' b, f b) * ∏' b, g b := (hf.hasProd.mul hg.hasProd).tprod_eq @[deprecated (since := "2025-04-12")] alias tsum_add := Summable.tsum_add @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_mul := Multipliable.tprod_mul @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Multipliable.tprod_mul
null
protected Multipliable.tprod_finsetProd {f : γ → β → α} {s : Finset γ} (hf : ∀ i ∈ s, Multipliable (f i)) : ∏' b, ∏ i ∈ s, f i b = ∏ i ∈ s, ∏' b, f i b := (hasProd_prod fun i hi ↦ (hf i hi).hasProd).tprod_eq @[deprecated (since := "2025-04-12")] alias tsum_finsetSum := Summable.tsum_finsetSum @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_finsetProd := Multipliable.tprod_finsetProd
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Multipliable.tprod_finsetProd
null
@[to_additive /-- Version of `tsum_eq_add_tsum_ite` for `AddCommMonoid` rather than `AddCommGroup`. Requires a different convergence assumption involving `Function.update`. -/] protected Multipliable.tprod_eq_mul_tprod_ite' [DecidableEq β] {f : β → α} (b : β) (hf : Multipliable (update f b 1)) : ∏' x, f x = f b * ∏' x, ite (x = b) 1 (f x) := calc ∏' x, f x = ∏' x, (ite (x = b) (f x) 1 * update f b 1 x) := tprod_congr fun n ↦ by split_ifs with h <;> simp [update_apply, h] _ = (∏' x, ite (x = b) (f x) 1) * ∏' x, update f b 1 x := Multipliable.tprod_mul ⟨ite (b = b) (f b) 1, hasProd_single b fun _ hb ↦ if_neg hb⟩ hf _ = ite (b = b) (f b) 1 * ∏' x, update f b 1 x := by congr exact tprod_eq_mulSingle b fun b' hb' ↦ if_neg hb' _ = f b * ∏' x, ite (x = b) 1 (f x) := by simp only [update, if_true, eq_rec_constant, dite_eq_ite] @[deprecated (since := "2025-04-12")] alias tsum_eq_add_tsum_ite' := Summable.tsum_eq_add_tsum_ite' @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_eq_mul_tprod_ite' := Multipliable.tprod_eq_mul_tprod_ite' @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Multipliable.tprod_eq_mul_tprod_ite'
Version of `tprod_eq_mul_tprod_ite` for `CommMonoid` rather than `CommGroup`. Requires a different convergence assumption involving `Function.update`.
protected Multipliable.tprod_mul_tprod_compl {s : Set β} (hs : Multipliable (f ∘ (↑) : s → α)) (hsc : Multipliable (f ∘ (↑) : ↑sᶜ → α)) : (∏' x : s, f x) * ∏' x : ↑sᶜ, f x = ∏' x, f x := (hs.hasProd.mul_compl hsc.hasProd).tprod_eq.symm @[deprecated (since := "2025-04-12")] alias tsum_add_tsum_compl := Summable.tsum_add_tsum_compl @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_mul_tprod_compl := Multipliable.tprod_mul_tprod_compl @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Multipliable.tprod_mul_tprod_compl
null
protected Multipliable.tprod_union_disjoint {s t : Set β} (hd : Disjoint s t) (hs : Multipliable (f ∘ (↑) : s → α)) (ht : Multipliable (f ∘ (↑) : t → α)) : ∏' x : ↑(s ∪ t), f x = (∏' x : s, f x) * ∏' x : t, f x := (hs.hasProd.mul_disjoint hd ht.hasProd).tprod_eq @[deprecated (since := "2025-04-12")] alias tsum_union_disjoint := Summable.tsum_union_disjoint @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_union_disjoint := Multipliable.tprod_union_disjoint @[to_additive]
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Multipliable.tprod_union_disjoint
null
protected Multipliable.tprod_finset_bUnion_disjoint {ι} {s : Finset ι} {t : ι → Set β} (hd : (s : Set ι).Pairwise (Disjoint on t)) (hf : ∀ i ∈ s, Multipliable (f ∘ (↑) : t i → α)) : ∏' x : ⋃ i ∈ s, t i, f x = ∏ i ∈ s, ∏' x : t i, f x := (hasProd_prod_disjoint _ hd fun i hi ↦ (hf i hi).hasProd).tprod_eq @[deprecated (since := "2025-04-12")] alias tsum_finset_bUnion_disjoint := Summable.tsum_finset_bUnion_disjoint @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_finset_bUnion_disjoint := Multipliable.tprod_finset_bUnion_disjoint
theorem
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
Multipliable.tprod_finset_bUnion_disjoint
null
hasProd_zero_of_exists_eq_zero (hf : ∃ b, f b = 0) : HasProd f 0 := by obtain ⟨b, hb⟩ := hf apply tendsto_const_nhds.congr' filter_upwards [eventually_ge_atTop {b}] with s hs exact (Finset.prod_eq_zero (Finset.singleton_subset_iff.mp hs) hb).symm
lemma
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
hasProd_zero_of_exists_eq_zero
null
multipliable_of_exists_eq_zero (hf : ∃ b, f b = 0) : Multipliable f := ⟨0, hasProd_zero_of_exists_eq_zero hf⟩
lemma
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
multipliable_of_exists_eq_zero
null
tprod_of_exists_eq_zero [T2Space α] (hf : ∃ b, f b = 0) : ∏' b, f b = 0 := (hasProd_zero_of_exists_eq_zero hf).tprod_eq
lemma
Topology
[ "Mathlib.Algebra.BigOperators.Group.Finset.Indicator", "Mathlib.Data.Fintype.BigOperators", "Mathlib.Topology.Algebra.InfiniteSum.Defs", "Mathlib.Topology.Algebra.Monoid.Defs" ]
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean
tprod_of_exists_eq_zero
null
@[to_additive] hasProd_pi_single [DecidableEq β] (b : β) (a : α) : HasProd (Pi.mulSingle b a) a := by convert hasProd_ite_eq b a simp [Pi.mulSingle_apply] @[to_additive (attr := simp)]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
hasProd_pi_single
null
tprod_pi_single [DecidableEq β] (b : β) (a : α) : ∏' b', Pi.mulSingle b a b' = a := by rw [tprod_eq_mulSingle b] · simp · intro b' hb'; simp [hb'] @[to_additive tsum_setProd_singleton_left]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
tprod_pi_single
null
tprod_setProd_singleton_left (b : β) (t : Set γ) (f : β × γ → α) : (∏' x : {b} ×ˢ t, f x) = ∏' c : t, f (b, c) := by rw [tprod_congr_set_coe _ Set.singleton_prod, tprod_image _ (Prod.mk_right_injective b).injOn] @[to_additive tsum_setProd_singleton_right]
lemma
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
tprod_setProd_singleton_left
null
tprod_setProd_singleton_right (s : Set β) (c : γ) (f : β × γ → α) : (∏' x : s ×ˢ {c}, f x) = ∏' b : s, f (b, c) := by rw [tprod_congr_set_coe _ Set.prod_singleton, tprod_image _ (Prod.mk_left_injective c).injOn] @[to_additive Summable.prod_symm]
lemma
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
tprod_setProd_singleton_right
null
Multipliable.prod_symm {f : β × γ → α} (hf : Multipliable f) : Multipliable fun p : γ × β ↦ f p.swap := (Equiv.prodComm γ β).multipliable_iff.2 hf
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.prod_symm
null
@[to_additive HasSum.prodMk] HasProd.prodMk {f : β → α} {g : β → γ} {a : α} {b : γ} (hf : HasProd f a) (hg : HasProd g b) : HasProd (fun x ↦ (⟨f x, g x⟩ : α × γ)) ⟨a, b⟩ := by simp [HasProd, ← prod_mk_prod, Filter.Tendsto.prodMk_nhds hf hg] @[deprecated (since := "2025-03-10")] alias HasSum.prod_mk := HasSum.prodMk @[to_additive existing HasSum.prodMk, deprecated (since := "2025-03-10")] alias HasProd.prod_mk := HasProd.prodMk
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasProd.prodMk
null
@[to_additive] HasProd.sum {α β M : Type*} [CommMonoid M] [TopologicalSpace M] [ContinuousMul M] {f : α ⊕ β → M} {a b : M} (h₁ : HasProd (f ∘ Sum.inl) a) (h₂ : HasProd (f ∘ Sum.inr) b) : HasProd f (a * b) := by have : Tendsto ((∏ b ∈ ·, f b) ∘ sumEquiv.symm) (atTop.map sumEquiv) (nhds (a * b)) := by rw [Finset.sumEquiv.map_atTop, ← prod_atTop_atTop_eq] convert (tendsto_mul.comp (nhds_prod_eq (x := a) (y := b) ▸ Tendsto.prodMap h₁ h₂)) ext s simp simpa [Tendsto, ← Filter.map_map] using this @[to_additive /-- For the statement that `tsum` commutes with `Finset.sum`, see `Summable.tsum_finsetSum`. -/]
lemma
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasProd.sum
null
protected Multipliable.tprod_sum {α β M : Type*} [CommMonoid M] [TopologicalSpace M] [ContinuousMul M] [T2Space M] {f : α ⊕ β → M} (h₁ : Multipliable (f ∘ .inl)) (h₂ : Multipliable (f ∘ .inr)) : ∏' i, f i = (∏' i, f (.inl i)) * (∏' i, f (.inr i)) := (h₁.hasProd.sum h₂.hasProd).tprod_eq @[deprecated (since := "2025-04-12")] alias tsum_sum := Summable.tsum_sum @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_sum := Multipliable.tprod_sum @[to_additive]
lemma
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.tprod_sum
null
Multipliable.sum {α β M : Type*} [CommMonoid M] [TopologicalSpace M] [ContinuousMul M] (f : α ⊕ β → M) (h₁ : Multipliable (f ∘ Sum.inl)) (h₂ : Multipliable (f ∘ Sum.inr)) : Multipliable f := ⟨_, .sum h₁.hasProd h₂.hasProd⟩
lemma
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.sum
null
@[to_additive] HasProd.sigma {γ : β → Type*} {f : (Σ b : β, γ b) → α} {g : β → α} {a : α} (ha : HasProd f a) (hf : ∀ b, HasProd (fun c ↦ f ⟨b, c⟩) (g b)) : HasProd g a := by classical refine (atTop_basis.tendsto_iff (closed_nhds_basis a)).mpr ?_ rintro s ⟨hs, hsc⟩ rcases mem_atTop_sets.mp (ha hs) with ⟨u, hu⟩ use u.image Sigma.fst, trivial intro bs hbs simp only [Set.mem_preimage, Finset.le_iff_subset] at hu have : Tendsto (fun t : Finset (Σ b, γ b) ↦ ∏ p ∈ t with p.1 ∈ bs, f p) atTop (𝓝 <| ∏ b ∈ bs, g b) := by simp only [← sigma_preimage_mk, prod_sigma] refine tendsto_finset_prod _ fun b _ ↦ ?_ change Tendsto (fun t ↦ (fun t ↦ ∏ s ∈ t, f ⟨b, s⟩) (preimage t (Sigma.mk b) _)) atTop (𝓝 (g b)) exact (hf b).comp (tendsto_finset_preimage_atTop_atTop (sigma_mk_injective)) refine hsc.mem_of_tendsto this (eventually_atTop.2 ⟨u, fun t ht ↦ hu _ fun x hx ↦ ?_⟩) exact mem_filter.2 ⟨ht hx, hbs <| mem_image_of_mem _ hx⟩
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasProd.sigma
null
@[to_additive HasSum.prod_fiberwise /-- If a series `f` on `β × γ` has sum `a` and for each `b` the restriction of `f` to `{b} × γ` has sum `g b`, then the series `g` has sum `a`. -/] HasProd.prod_fiberwise {f : β × γ → α} {g : β → α} {a : α} (ha : HasProd f a) (hf : ∀ b, HasProd (fun c ↦ f (b, c)) (g b)) : HasProd g a := HasProd.sigma ((Equiv.sigmaEquivProd β γ).hasProd_iff.2 ha) hf @[to_additive]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasProd.prod_fiberwise
If a function `f` on `β × γ` has product `a` and for each `b` the restriction of `f` to `{b} × γ` has product `g b`, then the function `g` has product `a`.
Multipliable.sigma' {γ : β → Type*} {f : (Σ b : β, γ b) → α} (ha : Multipliable f) (hf : ∀ b, Multipliable fun c ↦ f ⟨b, c⟩) : Multipliable fun b ↦ ∏' c, f ⟨b, c⟩ := (ha.hasProd.sigma fun b ↦ (hf b).hasProd).multipliable
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.sigma'
null
@[to_additive] HasProd.sigma_of_hasProd {γ : β → Type*} {f : (Σ b : β, γ b) → α} {g : β → α} {a : α} (ha : HasProd g a) (hf : ∀ b, HasProd (fun c ↦ f ⟨b, c⟩) (g b)) (hf' : Multipliable f) : HasProd f a := by simpa [(hf'.hasProd.sigma hf).unique ha] using hf'.hasProd @[to_additive]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasProd.sigma_of_hasProd
null
protected Multipliable.tprod_sigma' {γ : β → Type*} {f : (Σ b : β, γ b) → α} (h₁ : ∀ b, Multipliable fun c ↦ f ⟨b, c⟩) (h₂ : Multipliable f) : ∏' p, f p = ∏' (b) (c), f ⟨b, c⟩ := (h₂.hasProd.sigma fun b ↦ (h₁ b).hasProd).tprod_eq.symm @[deprecated (since := "2025-04-12")] alias tsum_sigma' := Summable.tsum_sigma' @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_sigma' := Multipliable.tprod_sigma' @[to_additive Summable.tsum_prod']
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.tprod_sigma'
null
protected Multipliable.tprod_prod' {f : β × γ → α} (h : Multipliable f) (h₁ : ∀ b, Multipliable fun c ↦ f (b, c)) : ∏' p, f p = ∏' (b) (c), f (b, c) := (h.hasProd.prod_fiberwise fun b ↦ (h₁ b).hasProd).tprod_eq.symm @[deprecated (since := "2025-04-12")] alias tsum_prod' := Summable.tsum_prod' @[to_additive existing Summable.tsum_prod', deprecated (since := "2025-04-12")] alias tprod_prod' := Multipliable.tprod_prod' @[to_additive Summable.tsum_prod_uncurry]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.tprod_prod'
null
protected Multipliable.tprod_prod_uncurry {f : β → γ → α} (h : Multipliable (Function.uncurry f)) (h₁ : ∀ b, Multipliable fun c ↦ f b c) : ∏' p : β × γ, uncurry f p = ∏' (b) (c), f b c := (h.hasProd.prod_fiberwise fun b ↦ (h₁ b).hasProd).tprod_eq.symm @[deprecated (since := "2025-04-12")] alias tsum_prod_uncurry := Summable.tsum_prod_uncurry @[to_additive existing Summable.tsum_prod_uncurry, deprecated (since := "2025-04-12")] alias tprod_prod_uncurry := Multipliable.tprod_prod_uncurry @[to_additive]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.tprod_prod_uncurry
null
protected Multipliable.tprod_comm' {f : β → γ → α} (h : Multipliable (Function.uncurry f)) (h₁ : ∀ b, Multipliable (f b)) (h₂ : ∀ c, Multipliable fun b ↦ f b c) : ∏' (c) (b), f b c = ∏' (b) (c), f b c := by rw [← h.tprod_prod_uncurry h₁, ← h.prod_symm.tprod_prod_uncurry h₂, ← (Equiv.prodComm γ β).tprod_eq (uncurry f)] rfl @[deprecated (since := "2025-04-12")] alias tsum_comm':= Summable.tsum_comm' @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_comm' := Multipliable.tprod_comm'
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.tprod_comm'
null
@[to_additive] HasProd.of_sigma {γ : β → Type*} {f : (Σ b : β, γ b) → α} {g : β → α} {a : α} (hf : ∀ b, HasProd (fun c ↦ f ⟨b, c⟩) (g b)) (hg : HasProd g a) (h : CauchySeq (fun (s : Finset (Σ b : β, γ b)) ↦ ∏ i ∈ s, f i)) : HasProd f a := by classical apply le_nhds_of_cauchy_adhp h simp only [← mapClusterPt_def, mapClusterPt_iff_frequently, frequently_atTop, ge_iff_le, le_eq_subset] intro u hu s rcases mem_nhds_iff.1 hu with ⟨v, vu, v_open, hv⟩ obtain ⟨t0, st0, ht0⟩ : ∃ t0, ∏ i ∈ t0, g i ∈ v ∧ s.image Sigma.fst ⊆ t0 := by have A : ∀ᶠ t0 in (atTop : Filter (Finset β)), ∏ i ∈ t0, g i ∈ v := hg (v_open.mem_nhds hv) exact (A.and (Ici_mem_atTop _)).exists have L : Tendsto (fun t : Finset (Σ b, γ b) ↦ ∏ p ∈ t with p.1 ∈ t0, f p) atTop (𝓝 <| ∏ b ∈ t0, g b) := by simp only [← sigma_preimage_mk, prod_sigma] refine tendsto_finset_prod _ fun b _ ↦ ?_ change Tendsto (fun t ↦ (fun t ↦ ∏ s ∈ t, f ⟨b, s⟩) (preimage t (Sigma.mk b) _)) atTop (𝓝 (g b)) exact (hf b).comp (tendsto_finset_preimage_atTop_atTop (sigma_mk_injective)) have : ∃ t, ∏ p ∈ t with p.1 ∈ t0, f p ∈ v ∧ s ⊆ t := ((Tendsto.eventually_mem L (v_open.mem_nhds st0)).and (Ici_mem_atTop _)).exists obtain ⟨t, tv, st⟩ := this refine ⟨{p ∈ t | p.1 ∈ t0}, fun x hx ↦ ?_, vu tv⟩ simpa only [mem_filter, st hx, true_and] using ht0 (mem_image_of_mem Sigma.fst hx) variable [CompleteSpace α] @[to_additive]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasProd.of_sigma
null
Multipliable.sigma_factor {γ : β → Type*} {f : (Σ b : β, γ b) → α} (ha : Multipliable f) (b : β) : Multipliable fun c ↦ f ⟨b, c⟩ := ha.comp_injective sigma_mk_injective @[to_additive]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.sigma_factor
null
Multipliable.sigma {γ : β → Type*} {f : (Σ b : β, γ b) → α} (ha : Multipliable f) : Multipliable fun b ↦ ∏' c, f ⟨b, c⟩ := ha.sigma' fun b ↦ ha.sigma_factor b @[to_additive Summable.prod_factor]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.sigma
null
Multipliable.prod_factor {f : β × γ → α} (h : Multipliable f) (b : β) : Multipliable fun c ↦ f (b, c) := h.comp_injective fun _ _ h ↦ (Prod.ext_iff.1 h).2 @[to_additive Summable.prod]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.prod_factor
null
Multipliable.prod {f : β × γ → α} (h : Multipliable f) : Multipliable fun b ↦ ∏' c, f (b, c) := ((Equiv.sigmaEquivProd β γ).multipliable_iff.mpr h).sigma @[to_additive]
lemma
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.prod
null
HasProd.tprod_fiberwise [T2Space α] {f : β → α} {a : α} (hf : HasProd f a) (g : β → γ) : HasProd (fun c : γ ↦ ∏' b : g ⁻¹' {c}, f b) a := (((Equiv.sigmaFiberEquiv g).hasProd_iff).mpr hf).sigma <| fun _ ↦ ((hf.multipliable.subtype _).hasProd_iff).mpr rfl
lemma
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasProd.tprod_fiberwise
null
@[to_additive] protected Multipliable.tprod_sigma {γ : β → Type*} {f : (Σ b : β, γ b) → α} (ha : Multipliable f) : ∏' p, f p = ∏' (b) (c), f ⟨b, c⟩ := Multipliable.tprod_sigma' (fun b ↦ ha.sigma_factor b) ha @[deprecated (since := "2025-04-12")] alias tsum_sigma := Summable.tsum_sigma @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_sigma := Multipliable.tprod_sigma @[to_additive Summable.tsum_prod]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.tprod_sigma
null
protected Multipliable.tprod_prod {f : β × γ → α} (h : Multipliable f) : ∏' p, f p = ∏' (b) (c), f ⟨b, c⟩ := h.tprod_prod' h.prod_factor @[deprecated (since := "2025-04-12")] alias tsum_prod := Summable.tsum_prod @[to_additive existing tsum_prod, deprecated (since := "2025-04-12")] alias tprod_prod := Multipliable.tprod_prod @[to_additive]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.tprod_prod
null
protected Multipliable.tprod_comm {f : β → γ → α} (h : Multipliable (Function.uncurry f)) : ∏' (c) (b), f b c = ∏' (b) (c), f b c := h.tprod_comm' h.prod_factor h.prod_symm.prod_factor @[deprecated (since := "2025-04-12")] alias tsum_comm := Summable.tsum_comm @[to_additive existing, deprecated (since := "2025-04-12")] alias tprod_comm := Multipliable.tprod_comm
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Multipliable.tprod_comm
null
@[to_additive] Pi.hasProd {f : ι → ∀ x, X x} {g : ∀ x, X x} : HasProd f g ↔ ∀ x, HasProd (fun i ↦ f i x) (g x) := by simp only [HasProd, tendsto_pi_nhds, prod_apply] @[to_additive]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Pi.hasProd
null
Pi.multipliable {f : ι → ∀ x, X x} : Multipliable f ↔ ∀ x, Multipliable fun i ↦ f i x := by simp only [Multipliable, Pi.hasProd, Classical.skolem] @[to_additive]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Pi.multipliable
null
tprod_apply [∀ x, T2Space (X x)] {f : ι → ∀ x, X x} {x : α} (hf : Multipliable f) : (∏' i, f i) x = ∏' i, f i x := (Pi.hasProd.mp hf.hasProd x).tprod_eq.symm
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
tprod_apply
null
HasSum.op (hf : HasSum f a) : HasSum (fun a ↦ op (f a)) (op a) := (hf.map (@opAddEquiv α _) continuous_op :)
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasSum.op
null
Summable.op (hf : Summable f) : Summable (op ∘ f) := hf.hasSum.op.summable
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Summable.op
null
HasSum.unop {f : β → αᵐᵒᵖ} {a : αᵐᵒᵖ} (hf : HasSum f a) : HasSum (fun a ↦ unop (f a)) (unop a) := (hf.map (@opAddEquiv α _).symm continuous_unop :)
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasSum.unop
null
Summable.unop {f : β → αᵐᵒᵖ} (hf : Summable f) : Summable (unop ∘ f) := hf.hasSum.unop.summable @[simp]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Summable.unop
null
hasSum_op : HasSum (fun a ↦ op (f a)) (op a) ↔ HasSum f a := ⟨HasSum.unop, HasSum.op⟩ @[simp]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
hasSum_op
null
hasSum_unop {f : β → αᵐᵒᵖ} {a : αᵐᵒᵖ} : HasSum (fun a ↦ unop (f a)) (unop a) ↔ HasSum f a := ⟨HasSum.op, HasSum.unop⟩ @[simp]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
hasSum_unop
null
summable_op : (Summable fun a ↦ op (f a)) ↔ Summable f := ⟨Summable.unop, Summable.op⟩
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
summable_op
null
summable_unop {f : β → αᵐᵒᵖ} : (Summable fun a ↦ unop (f a)) ↔ Summable f := ⟨Summable.op, Summable.unop⟩
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
summable_unop
null
tsum_op [T2Space α] : ∑' x, op (f x) = op (∑' x, f x) := by by_cases h : Summable f · exact h.hasSum.op.tsum_eq · have ho := summable_op.not.mpr h rw [tsum_eq_zero_of_not_summable h, tsum_eq_zero_of_not_summable ho, op_zero]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
tsum_op
null
tsum_unop [T2Space α] {f : β → αᵐᵒᵖ} : ∑' x, unop (f x) = unop (∑' x, f x) := op_injective tsum_op.symm
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
tsum_unop
null
HasSum.star (h : HasSum f a) : HasSum (fun b ↦ star (f b)) (star a) := by simpa only using h.map (starAddEquiv : α ≃+ α) continuous_star
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
HasSum.star
null
Summable.star (hf : Summable f) : Summable fun b ↦ star (f b) := hf.hasSum.star.summable
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Summable.star
null
Summable.ofStar (hf : Summable fun b ↦ Star.star (f b)) : Summable f := by simpa only [star_star] using hf.star @[simp]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
Summable.ofStar
null
summable_star_iff : (Summable fun b ↦ star (f b)) ↔ Summable f := ⟨Summable.ofStar, Summable.star⟩ @[simp]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
summable_star_iff
null
summable_star_iff' : Summable (star f) ↔ Summable f := summable_star_iff
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
summable_star_iff'
null
tsum_star [T2Space α] : star (∑' b, f b) = ∑' b, star (f b) := by by_cases hf : Summable f · exact hf.hasSum.star.tsum_eq.symm · rw [tsum_eq_zero_of_not_summable hf, tsum_eq_zero_of_not_summable (mt Summable.ofStar hf), star_zero]
theorem
Topology
[ "Mathlib.Order.Filter.AtTopBot.Finset", "Mathlib.Topology.Algebra.InfiniteSum.Group", "Mathlib.Topology.Algebra.Star" ]
Mathlib/Topology/Algebra/InfiniteSum/Constructions.lean
tsum_star
null
@[to_additive /-- `Summable f` means that `f` has some (infinite) sum. Use `tsum` to get the value. -/] Multipliable (f : β → α) : Prop := ∃ a, HasProd f a open scoped Classical in
def
Topology
[ "Mathlib.Algebra.BigOperators.Finprod", "Mathlib.Order.Filter.AtTopBot.BigOperators", "Mathlib.Topology.Separation.Hausdorff" ]
Mathlib/Topology/Algebra/InfiniteSum/Defs.lean
Multipliable
`HasProd f a` means that the (potentially infinite) product of the `f b` for `b : β` converges to `a`. The `atTop` filter on `Finset β` is the limit of all finite sets towards the entire type. So we take the product over bigger and bigger sets. This product operation is invariant under reordering. For the definition and many statements, `α` does not need to be a topological monoid. We only add this assumption later, for the lemmas where it is relevant. These are defined in an identical way to infinite sums (`HasSum`). For example, we say that the function `ℕ → ℝ` sending `n` to `1 / 2` has a product of `0`, rather than saying that it does not converge as some authors would. -/ @[to_additive /-- `HasSum f a` means that the (potentially infinite) sum of the `f b` for `b : β` converges to `a`. The `atTop` filter on `Finset β` is the limit of all finite sets towards the entire type. So we sum up bigger and bigger sets. This sum operation is invariant under reordering. In particular, the function `ℕ → ℝ` sending `n` to `(-1)^n / (n+1)` does not have a sum for this definition, but a series which is absolutely convergent will have the correct sum. This is based on Mario Carneiro's [infinite sum `df-tsms` in Metamath](http://us.metamath.org/mpeuni/df-tsms.html). For the definition and many statements, `α` does not need to be a topological monoid. We only add this assumption later, for the lemmas where it is relevant. -/] def HasProd (f : β → α) (a : α) : Prop := Tendsto (fun s : Finset β ↦ ∏ b ∈ s, f b) atTop (𝓝 a) /-- `Multipliable f` means that `f` has some (infinite) product. Use `tprod` to get the value.