Tagged partitions #
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A tagged (pre)partition is a (pre)partition π
enriched with a tagged point for each box of
‵π. For simplicity we require that the function
box_integral.tagged_prepartition.tagis defined on all boxes
J : box ιbut use its values only on boxes of the partition. Given
π :
box_integral.tagged_partition I, we require that each
box_integral.tagged_partition π Jbelongs to
box_integral.box.Icc I. If for every
J ∈ π,
π.tag Jbelongs to
J.Icc, then
π` is called
a Henstock partition. We do not include this assumption into the definition of a tagged
(pre)partition because McShane integral is defined as a limit along tagged partitions without this
requirement.
Tags #
rectangular box, box partition
- to_prepartition : box_integral.prepartition I
- tag : box_integral.box ι → ι → ℝ
- tag_mem_Icc : ∀ (J : box_integral.box ι), self.tag J ∈ ⇑box_integral.box.Icc I
A tagged prepartition is a prepartition enriched with a tagged point for each box of the
prepartition. For simiplicity we require that tag
is defined for all boxes in ι → ℝ
but
we will use onle the values of tag
on the boxes of the partition.
Instances for box_integral.tagged_prepartition
- box_integral.tagged_prepartition.has_sizeof_inst
- box_integral.tagged_prepartition.has_mem
- box_integral.tagged_prepartition.inhabited
Equations
- box_integral.tagged_prepartition.has_mem = {mem := λ (J : box_integral.box ι) (π : box_integral.tagged_prepartition I), J ∈ π.to_prepartition.boxes}
Union of all boxes of a tagged prepartition.
Equations
- π.Union = π.to_prepartition.Union
A tagged prepartition is a partition if it covers the whole box.
Equations
The tagged partition made of boxes of π
that satisfy predicate p
.
Equations
- π.filter p = {to_prepartition := π.to_prepartition.filter p, tag := π.tag, tag_mem_Icc := _}
Given a partition π
of I : box_integral.box ι
and a collection of tagged partitions
πi J
of all boxes J ∈ π
, returns the tagged partition of I
into all the boxes of πi J
with tags coming from (πi J).tag
.
Equations
- π.bUnion_tagged πi = {to_prepartition := π.bUnion (λ (J : box_integral.box ι), (πi J).to_prepartition), tag := λ (J : box_integral.box ι), (πi (π.bUnion_index (λ (J : box_integral.box ι), (πi J).to_prepartition) J)).tag J, tag_mem_Icc := _}
Given a tagged partition π
of I
and a (not tagged) partition πi J hJ
of each J ∈ π
,
returns the tagged partition of I
into all the boxes of all πi J hJ
. The tag of a box J
is defined to be the π.tag
of the box of the partition π
that includes J
.
Note that usually the result is not a Henstock partition.
Equations
- π.bUnion_prepartition πi = {to_prepartition := π.to_prepartition.bUnion πi, tag := λ (J : box_integral.box ι), π.tag (π.to_prepartition.bUnion_index πi J), tag_mem_Icc := _}
Given two partitions π₁
and π₁
, one of them tagged and the other is not, returns the tagged
partition with to_partition = π₁.to_partition ⊓ π₂
and tags coming from π₁
.
Note that usually the result is not a Henstock partition.
Equations
- π.inf_prepartition π' = π.bUnion_prepartition (λ (J : box_integral.box ι), π'.restrict J)
A tagged partition is said to be a Henstock partition if for each J ∈ π
, the tag of J
belongs to J.Icc
.
Equations
- π.is_Henstock = ∀ (J : box_integral.box ι), J ∈ π → π.tag J ∈ ⇑box_integral.box.Icc J
In a Henstock prepartition, there are at most 2 ^ fintype.card ι
boxes with a given tag.
A tagged partition π
is subordinate to r : (ι → ℝ) → ℝ
if each box J ∈ π
is included in
the closed ball with center π.tag J
and radius r (π.tag J)
.
Equations
- π.is_subordinate r = ∀ (J : box_integral.box ι), J ∈ π → ⇑box_integral.box.Icc J ⊆ metric.closed_ball (π.tag J) ↑(r (π.tag J))
Tagged prepartition with single box and prescribed tag.
Equations
- box_integral.tagged_prepartition.single I J hJ x h = {to_prepartition := box_integral.prepartition.single I J hJ, tag := λ (J : box_integral.box ι), x, tag_mem_Icc := _}
Equations
Union of two tagged prepartitions with disjoint unions of boxes.
Equations
- π₁.disj_union π₂ h = {to_prepartition := π₁.to_prepartition.disj_union π₂.to_prepartition h, tag := π₁.to_prepartition.boxes.piecewise π₁.tag π₂.tag (λ (j : box_integral.box ι), finset.decidable_mem j π₁.to_prepartition.boxes), tag_mem_Icc := _}
If I ≤ J
, then every tagged prepartition of I
is a tagged prepartition of J
.
Equations
- box_integral.tagged_prepartition.embed_box I J h = {to_fun := λ (π : box_integral.tagged_prepartition I), {to_prepartition := {boxes := π.to_prepartition.boxes, le_of_mem' := _, pairwise_disjoint := _}, tag := π.tag, tag_mem_Icc := _}, inj' := _}
The distortion of a tagged prepartition is the maximum of distortions of its boxes.