English
The Hausdorff distance to the empty set vanishes: hausdorffDist(s, ∅) = 0.
Русский
Расстояние Хаусдорфа до пустого множества равно нулю: hausdorffDist(s, ∅) = 0.
LaTeX
$$$\operatorname{hausdorffDist}(s,\varnothing)=0.$$$
Lean4
/-- The Hausdorff distance to the empty set vanishes (if you want to have the more reasonable
value `∞` instead, use `EMetric.hausdorffEdist`, which takes values in `ℝ≥0∞`). -/
@[simp]
theorem hausdorffDist_empty : hausdorffDist s ∅ = 0 :=
by
rcases s.eq_empty_or_nonempty with h | h
· simp [h]
· simp [hausdorffDist, hausdorffEdist_empty h]