Documentation

Mathlib.Logic.Embedding.Set

Interactions between embeddings and sets. #

@[simp]
theorem Equiv.asEmbedding_range {α : Sort u_1} {β : Type u_2} {p : βProp} (e : α Subtype p) :
@[simp]
theorem Function.Embedding.coeWithTop_apply {α : Type u_1} :
∀ (a : α), Function.Embedding.coeWithTop a = a

Embedding into WithTop α.

Equations
  • Function.Embedding.coeWithTop = let __src := Function.Embedding.some; { toFun := WithTop.some, inj' := }
@[simp]
theorem Function.Embedding.optionElim_apply {α : Type u_1} {β : Type u_2} (f : α β) (x : β) (h : xSet.range f) :
∀ (a : Option α), (Function.Embedding.optionElim f x h) a = Option.elim' x (f) a
def Function.Embedding.optionElim {α : Type u_1} {β : Type u_2} (f : α β) (x : β) (h : xSet.range f) :
Option α β

Given an embedding f : α ↪ β and a point outside of Set.range f, construct an embedding Option α ↪ β.

Equations
@[simp]
theorem Function.Embedding.optionEmbeddingEquiv_apply_fst (α : Type u_1) (β : Type u_2) (f : Option α β) :
((Function.Embedding.optionEmbeddingEquiv α β) f).fst = Function.Embedding.trans Function.Embedding.coeWithTop f
@[simp]
theorem Function.Embedding.optionEmbeddingEquiv_symm_apply (α : Type u_1) (β : Type u_2) (f : (f : α β) × (Set.range f)) :
@[simp]
theorem Function.Embedding.optionEmbeddingEquiv_apply_snd_coe (α : Type u_1) (β : Type u_2) (f : Option α β) :
((Function.Embedding.optionEmbeddingEquiv α β) f).snd = f none
def Function.Embedding.optionEmbeddingEquiv (α : Type u_1) (β : Type u_2) :
(Option α β) (f : α β) × (Set.range f)

Equivalence between embeddings of Option α and a sigma type over the embeddings of α.

Equations
  • One or more equations did not get rendered due to their size.
def Function.Embedding.codRestrict {α : Sort u_1} {β : Type u_2} (p : Set β) (f : α β) (H : ∀ (a : α), f a p) :
α p

Restrict the codomain of an embedding.

Equations
@[simp]
theorem Function.Embedding.codRestrict_apply {α : Sort u_1} {β : Type u_2} (p : Set β) (f : α β) (H : ∀ (a : α), f a p) (a : α) :
(Function.Embedding.codRestrict p f H) a = { val := f a, property := }
@[simp]
theorem Function.Embedding.image_apply {α : Type u_1} {β : Type u_2} (f : α β) (s : Set α) :
def Function.Embedding.image {α : Type u_1} {β : Type u_2} (f : α β) :
Set α Set β

Set.image as an embedding Set α ↪ Set β.

Equations
@[simp]
theorem Set.embeddingOfSubset_apply {α : Type u_1} (s : Set α) (t : Set α) (h : s t) (x : s) :
(Set.embeddingOfSubset s t h) x = { val := x, property := }
def Set.embeddingOfSubset {α : Type u_1} (s : Set α) (t : Set α) (h : s t) :
s t

The injection map is an embedding between subsets.

Equations
@[simp]
theorem subtypeOrEquiv_apply {α : Type u_1} (p : αProp) (q : αProp) [DecidablePred p] (h : Disjoint p q) (a : { x : α // p x q x }) :
def subtypeOrEquiv {α : Type u_1} (p : αProp) (q : αProp) [DecidablePred p] (h : Disjoint p q) :
{ x : α // p x q x } { x : α // p x } { x : α // q x }

A subtype {x // p x ∨ q x} over a disjunction of p q : α → Prop is equivalent to a sum of subtypes {x // p x} ⊕ {x // q x} such that ¬ p x is sent to the right, when Disjoint p q.

See also Equiv.sumCompl, for when IsCompl p q.

Equations
  • One or more equations did not get rendered due to their size.
@[simp]
theorem subtypeOrEquiv_symm_inl {α : Type u_1} (p : αProp) (q : αProp) [DecidablePred p] (h : Disjoint p q) (x : { x : α // p x }) :
(subtypeOrEquiv p q h).symm (Sum.inl x) = { val := x, property := }
@[simp]
theorem subtypeOrEquiv_symm_inr {α : Type u_1} (p : αProp) (q : αProp) [DecidablePred p] (h : Disjoint p q) (x : { x : α // q x }) :
(subtypeOrEquiv p q h).symm (Sum.inr x) = { val := x, property := }