Relations holding pairwise #
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In this file we prove many facts about pairwise
and the set lattice.
theorem
set.pairwise_disjoint_Union
{α : Type u_1}
{ι : Type u_4}
{ι' : Type u_5}
[partial_order α]
[order_bot α]
{f : ι → α}
{g : ι' → set ι}
(h : directed has_subset.subset g) :
(⋃ (n : ι'), g n).pairwise_disjoint f ↔ ∀ ⦃n : ι'⦄, (g n).pairwise_disjoint f
theorem
set.pairwise_disjoint_sUnion
{α : Type u_1}
{ι : Type u_4}
[partial_order α]
[order_bot α]
{f : ι → α}
{s : set (set ι)}
(h : directed_on has_subset.subset s) :
(⋃₀ s).pairwise_disjoint f ↔ ∀ ⦃a : set ι⦄, a ∈ s → a.pairwise_disjoint f
theorem
set.pairwise_disjoint.bUnion
{α : Type u_1}
{ι : Type u_4}
{ι' : Type u_5}
[complete_lattice α]
{s : set ι'}
{g : ι' → set ι}
{f : ι → α}
(hs : s.pairwise_disjoint (λ (i' : ι'), ⨆ (i : ι) (H : i ∈ g i'), f i))
(hg : ∀ (i : ι'), i ∈ s → (g i).pairwise_disjoint f) :
(⋃ (i : ι') (H : i ∈ s), g i).pairwise_disjoint f
Bind operation for set.pairwise_disjoint
. If you want to only consider finsets of indices, you
can use set.pairwise_disjoint.bUnion_finset
.
theorem
set.pairwise_disjoint.prod_left
{α : Type u_1}
{ι : Type u_4}
{ι' : Type u_5}
[complete_lattice α]
{s : set ι}
{t : set ι'}
{f : ι × ι' → α}
(hs : s.pairwise_disjoint (λ (i : ι), ⨆ (i' : ι') (H : i' ∈ t), f (i, i')))
(ht : t.pairwise_disjoint (λ (i' : ι'), ⨆ (i : ι) (H : i ∈ s), f (i, i'))) :
(s ×ˢ t).pairwise_disjoint f
If the suprema of columns are pairwise disjoint and suprema of rows as well, then everything is
pairwise disjoint. Not to be confused with set.pairwise_disjoint.prod
.
theorem
set.pairwise_disjoint_prod_left
{α : Type u_1}
{ι : Type u_4}
{ι' : Type u_5}
[order.frame α]
{s : set ι}
{t : set ι'}
{f : ι × ι' → α} :
(s ×ˢ t).pairwise_disjoint f ↔ s.pairwise_disjoint (λ (i : ι), ⨆ (i' : ι') (H : i' ∈ t), f (i, i')) ∧ t.pairwise_disjoint (λ (i' : ι'), ⨆ (i : ι) (H : i ∈ s), f (i, i'))
noncomputable
def
set.bUnion_eq_sigma_of_disjoint
{α : Type u_1}
{ι : Type u_4}
{s : set ι}
{f : ι → set α}
(h : s.pairwise_disjoint f) :
Equivalence between a disjoint bounded union and a dependent sum.
Equations
- set.bUnion_eq_sigma_of_disjoint h = (equiv.set_congr set.bUnion_eq_sigma_of_disjoint._proof_1).trans (set.Union_eq_sigma_of_disjoint _)