Function reach_set2_backward 

pub fn reach_set2_backward(
    problem: &Topp2Problem<'_>,
    options: &ReachSet2Options,
) -> Result<ReachSet2, CoppError>

Compute backward-only reachable intervals of $a(s)=\dot{s}^2$ using Reachability Analysis.

Performs a single backward pass from the terminal boundary; the start boundary is not enforced. Use this when only the terminal state is constrained, or as an intermediate step before bidirectional analysis.

Returns

ReachSet2 with a_min[k] <= a[k] <= a_max[k] for every station.

Errors

Returns CoppError when boundary states are infeasible, LP subproblems fail, or numerical comparisons violate configured tolerances.

Contract

• problem indices and boundaries must be consistent with the constraints domain.
• options tolerances must be positive and numerically meaningful.