OAI/Analysis/LipschitzHilbert/Geometry/DyadicLineCover.lean
3 declarations, 0 contain sorry, 0 declared as axioms
A uniform interval cover by the nested one-third dyadic grids.
- theorem
OAI.LipschitzHilbert.DyadicLineGrid.unit_interval_coverline 14Source documentation
The elementary one-third covering step at a fixed scale.
theorem unit_interval_cover {a b δ : ℝ} (hδ0 : 1 / 3 ≤ δ) (hδ1 : δ ≤ 2 / 3) (hlen : b - a < 1 / 3) : (∃ j : ℤ, Icc a b ⊆ Ico (j : ℝ) (j + 1)) ∨ ∃ j : ℤ, Icc a b ⊆ Ico ((j : ℝ) + δ) (j + 1 + δ) := by … - theorem
OAI.LipschitzHilbert.DyadicLineGrid.fixed_scale_interval_coverline 33Source documentation
Each interval shorter than one third of a grid cell fits in one cell of the ordinary or alternating one-third grid.
theorem fixed_scale_interval_cover (k : ℤ) {a b : ℝ} (hlen : b - a < scale k / 3) : ∃ q ∈ ({0, 1} : Finset ℤ), ∃ j : ℤ, Icc a b ⊆ cell q k j := by …Mentions: OAI.LipschitzHilbert.DyadicLineGrid.scale, OAI.LipschitzHilbert.DyadicLineGrid.cell
- theorem
OAI.LipschitzHilbert.DyadicLineGrid.interval_coverline 87Source documentation
A positive-length interval is contained in a dyadic interval of length at most six times its own, with one of two fixed nested grids.
theorem interval_cover {a b : ℝ} (hab : a < b) : ∃ q ∈ ({0, 1} : Finset ℤ), ∃ k j : ℤ, Icc a b ⊆ cell q k j ∧ scale k ≤ 6 * (b - a) := by …Mentions: OAI.LipschitzHilbert.DyadicLineGrid.cell, OAI.LipschitzHilbert.DyadicLineGrid.scale