English
For a subgraph G' of G that is IsSpanning, the spanningCoe (the embedding of the spanning subgraph) is isomorphic to the underlying coe graph: G'.spanningCoe ≃g G'.coe.
Русский
Для подграфа G' графа G, который является IsSpanning, отношение spanningCoe эквивалентно подграфу coe: существует изоморфизм G'.spanningCoe ≃g G'.coe.
LaTeX
$$$\forall (G' : G.Subgraph) (h : G'.IsSpanning),\; G'.spanningCoe \cong_g G'.coe.$$$
Lean4
/-- `spanningCoe` is equivalent to `coe` for a subgraph that `IsSpanning`. -/
@[simps]
def spanningCoeEquivCoeOfSpanning (G' : Subgraph G) (h : G'.IsSpanning) : G'.spanningCoe ≃g G'.coe
where
toFun v := ⟨v, h v⟩
invFun v := v
map_rel_iff' := Iff.rfl