Documentation

Mathlib.Algebra.Homology.HasNoLoop

Complex shapes with no loop #

Let c : ComplexShape ι. We define a type class c.HasNoLoop which expresses that ¬ c.Rel i i for all i : ι.

class ComplexShape.HasNoLoop {ι : Type u_1} (c : ComplexShape ι) :

The condition that c.Rel i i does not hold for any i.

  • not_rel_self (i : ι) : ¬c.Rel i i
Instances
    theorem ComplexShape.not_rel_self {ι : Type u_1} (c : ComplexShape ι) [c.HasNoLoop] (j : ι) :
    ¬c.Rel j j
    theorem ComplexShape.not_rel_of_eq {ι : Type u_1} (c : ComplexShape ι) [c.HasNoLoop] {j j' : ι} (h : j = j') :
    ¬c.Rel j j'
    theorem ComplexShape.exists_distinct_prev_or {ι : Type u_1} (c : ComplexShape ι) [c.HasNoLoop] (j : ι) :
    (∃ (k : ι), c.Rel j k j k) ∀ (k : ι), ¬c.Rel j k
    theorem ComplexShape.exists_distinct_next_or {ι : Type u_1} (c : ComplexShape ι) [c.HasNoLoop] (j : ι) :
    (∃ (i : ι), c.Rel i j i j) ∀ (i : ι), ¬c.Rel i j