Local Level Lab

Airborne measurements. Open methods.

Qualify bounded steps within timing intervals

The completed timing diagnostic finds correct local derivatives but an unreliable compensating step across an integration boundary. The next component should keep a proposed linear step inside the interval whose derivatives describe it, while considering both adjacent intervals and retaining every calibration coordinate.

Software component first

Add a shared bounded linear-step component. Its inputs are a complete residual, Jacobian, anchor point and physical box for each feasible timing interval. Its output is a proposed step and predicted residual cost, not convergence, uncertainty or a scientific decision. Charge each linear solve before execution; use the existing bvls tolerance 1e-10 and 100-iteration ceiling.

Qualify smooth interior minima, internal-boundary minima, physical-bound minima, coupled coordinates, redundant/zero columns, invalid boxes and exhausted charges. Use independent closed-form minima or explicit low-dimensional face enumeration as references. Preserve all 27 columns in the rank-deficient controls; agreement in predicted observations does not require unique nuisance parameters.

Implement the shared algebra in lll.timing_cells, with a small lll.timing_cell_study definition/evaluator and a saved-only lll.timing_cell_report. Use one lifecycle task containing all 18 solves and an append-only charge journal. The study has zero native-call allowance.

Bounded saved-matrix review

After those checks pass, use all 18 feasible branch matrices already saved by the four-point timing diagnostic: three distances on each feasible side. Do not select only a favorable spacing. Each box retains the original physical bounds and limits timing to its adjacent integration interval, clipped at the physical offset limits. Verify the parent manifest, source-fit hashes and column order.

Allow exactly one solve per saved matrix: 18 charged linear solves, one thread, 100 iterations per solve and a ten-minute cooperative ceiling. Preserve failed or interrupted solves; no retries. Generate no measurements, noise, native calculations, forecasts or nonlinear fits. The prior diagnostic and calibration allowances remain closed.

Compare proposals across sides and spacings, reporting predicted costs and parameter-bound activity. These are linear predictions, not independently evaluated physical costs. They cannot relabel the original failed fits.

Next gate

Only after the component qualifies should a separate finite native diagnostic evaluate its proposals. A complete boundary-aware optimizer still needs known optima, repeatability and physical prediction checks before fresh calibration. Keep the original cost, stationarity and position-change limits throughout.

Next analyses · Roadmap.