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 functionbox_integral.tagged_prepartition.tagis defined on all boxesJ : box ιbut use its values only on boxes of the partition. Givenπ :
box_integral.tagged_partition I, we require that eachbox_integral.tagged_partition π Jbelongs tobox_integral.box.Icc I. If for everyJ ∈ π,π.tag Jbelongs toJ.Icc, thenπ` 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.