pub fn intrinsic_chord_bound3(
curve: &Intrinsic3,
a: Scalar,
b: Scalar,
) -> Option<Scalar>Expand description
Certified chord bound of a 3D intrinsic curve over [a, b]: h^2 / 8 sigma sup |k|, whatever its torsion (|c''| = |k|). None outside
[0, length] or for a curvature law with no closed-form bound.