English
For the top prepartition π0 = ⊤, the filter (l.toFilterDistortioniUnion I c ⊤) has a basis as above with π.iUnion = ⊤ iUnion.
Русский
Для верхнего разбиения π0 = ⊤ фильтр (l.toFilterDistortioniUnion I c ⊤) имеет базис аналогично предыдущему с π.iUnion = ⊤.
LaTeX
$$$(l.toFilterDistortioniUnion I c \\top).HasBasis l.RCond \\; (\\lambda r. {\\pi \\mid l.MemBaseSet I c r \\pi \\land \\pi.iUnion = π.iUnion_{Top}})$$$
Lean4
theorem hasBasis_toFilterDistortion (l : IntegrationParams) (I : Box ι) (c : ℝ≥0) :
(l.toFilterDistortion I c).HasBasis l.RCond fun r => {π | l.MemBaseSet I c r π} :=
hasBasis_biInf_principal'
(fun _ hr₁ _ hr₂ =>
⟨_, hr₁.min hr₂, fun _ => MemBaseSet.mono _ le_rfl le_rfl fun _ _ => min_le_left _ _, fun _ =>
MemBaseSet.mono _ le_rfl le_rfl fun _ _ => min_le_right _ _⟩)
⟨fun _ => ⟨1, Set.mem_Ioi.2 zero_lt_one⟩, fun _ _ => rfl⟩