Conditionally complete lattices and finite sets. #
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theorem
finset.nonempty.sup'_eq_cSup_image
    {α : Type u_1}
    {β : Type u_2}
    [conditionally_complete_lattice α]
    {s : finset β}
    (hs : s.nonempty)
    (f : β → α) :
s.sup' hs f = has_Sup.Sup (f '' ↑s)
    
theorem
finset.nonempty.sup'_id_eq_cSup
    {α : Type u_1}
    [conditionally_complete_lattice α]
    {s : finset α}
    (hs : s.nonempty) :
s.sup' hs id = has_Sup.Sup ↑s
    
theorem
finset.nonempty.cSup_eq_max'
    {α : Type u_1}
    [conditionally_complete_linear_order α]
    {s : finset α}
    (h : s.nonempty) :
has_Sup.Sup ↑s = s.max' h
    
theorem
finset.nonempty.cInf_eq_min'
    {α : Type u_1}
    [conditionally_complete_linear_order α]
    {s : finset α}
    (h : s.nonempty) :
has_Inf.Inf ↑s = s.min' h
    
theorem
finset.nonempty.cSup_mem
    {α : Type u_1}
    [conditionally_complete_linear_order α]
    {s : finset α}
    (h : s.nonempty) :
has_Sup.Sup ↑s ∈ s
    
theorem
finset.nonempty.cInf_mem
    {α : Type u_1}
    [conditionally_complete_linear_order α]
    {s : finset α}
    (h : s.nonempty) :
has_Inf.Inf ↑s ∈ s
    
theorem
set.nonempty.cSup_mem
    {α : Type u_1}
    [conditionally_complete_linear_order α]
    {s : set α}
    (h : s.nonempty)
    (hs : s.finite) :
has_Sup.Sup s ∈ s
    
theorem
set.nonempty.cInf_mem
    {α : Type u_1}
    [conditionally_complete_linear_order α]
    {s : set α}
    (h : s.nonempty)
    (hs : s.finite) :
has_Inf.Inf s ∈ s
    
theorem
set.finite.cSup_lt_iff
    {α : Type u_1}
    [conditionally_complete_linear_order α]
    {s : set α}
    {a : α}
    (hs : s.finite)
    (h : s.nonempty) :
    
theorem
set.finite.lt_cInf_iff
    {α : Type u_1}
    [conditionally_complete_linear_order α]
    {s : set α}
    {a : α}
    (hs : s.finite)
    (h : s.nonempty) :
Relation between Sup / Inf and finset.sup' / finset.inf' #
Like the Sup of a conditionally_complete_lattice, finset.sup' also requires the set to be
non-empty. As a result, we can translate between the two.
    
theorem
finset.sup'_eq_cSup_image
    {α : Type u_1}
    {β : Type u_2}
    [conditionally_complete_lattice β]
    (s : finset α)
    (H : s.nonempty)
    (f : α → β) :
s.sup' H f = has_Sup.Sup (f '' ↑s)
    
theorem
finset.inf'_eq_cInf_image
    {α : Type u_1}
    {β : Type u_2}
    [conditionally_complete_lattice β]
    (s : finset α)
    (H : s.nonempty)
    (f : α → β) :
s.inf' H f = has_Inf.Inf (f '' ↑s)
    
theorem
finset.sup'_id_eq_cSup
    {α : Type u_1}
    [conditionally_complete_lattice α]
    (s : finset α)
    (H : s.nonempty) :
s.sup' H id = has_Sup.Sup ↑s
    
theorem
finset.inf'_id_eq_cInf
    {α : Type u_1}
    [conditionally_complete_lattice α]
    (s : finset α)
    (H : s.nonempty) :
s.inf' H id = has_Inf.Inf ↑s