Documentation

Mathlib.Order.Bounds.OrderIso

Order isomorphisms and bounds. #

theorem OrderIso.upperBounds_image {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set α} :
upperBounds (⇑f '' s) = ⇑f '' upperBounds s
theorem OrderIso.lowerBounds_image {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set α} :
lowerBounds (⇑f '' s) = ⇑f '' lowerBounds s
@[simp]
theorem OrderIso.isLUB_image {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set α} {x : β} :
IsLUB (⇑f '' s) x ↔ IsLUB s (f.symm x)
theorem OrderIso.isLUB_image' {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set α} {x : α} :
IsLUB (⇑f '' s) (f x) ↔ IsLUB s x
@[simp]
theorem OrderIso.isGLB_image {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set α} {x : β} :
IsGLB (⇑f '' s) x ↔ IsGLB s (f.symm x)
theorem OrderIso.isGLB_image' {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set α} {x : α} :
IsGLB (⇑f '' s) (f x) ↔ IsGLB s x
@[simp]
theorem OrderIso.isLUB_preimage {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set β} {x : α} :
IsLUB (⇑f ⁻¹' s) x ↔ IsLUB s (f x)
theorem OrderIso.isLUB_preimage' {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set β} {x : β} :
IsLUB (⇑f ⁻¹' s) (f.symm x) ↔ IsLUB s x
@[simp]
theorem OrderIso.isGLB_preimage {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set β} {x : α} :
IsGLB (⇑f ⁻¹' s) x ↔ IsGLB s (f x)
theorem OrderIso.isGLB_preimage' {α : Type u_1} {β : Type u_2} [Preorder α] [Preorder β] (f : α ≃o β) {s : Set β} {x : β} :
IsGLB (⇑f ⁻¹' s) (f.symm x) ↔ IsGLB s x