Adds a many-objective section to the comparison harness, exercising the
regime where Pareto dominance stops discriminating: with enough
objectives almost every pair of solutions is mutually non-dominated.
- DTLZ2 4-objective: the entry point to many-objective.
- DTLZ2 10-objective: the curse of dimensionality in full.
- DTLZ1 8-objective: dominance collapse stacked on DTLZ1's deceptive
multimodal g-term.
Implemented generically: the existing Dtlz1/Dtlz2 structs and distance
metrics are already objective-count agnostic, so a single `ManySpec` +
nine generic runners (RandomSearch, NSGA-II, NSGA-III, MOEA/D, RVEA,
GrEA, IBEA, HypE, AGE-MOEA) cover all three tables -- and any future M.
The results are a clean teaching story:
- NSGA-II collapses -- on DTLZ2-10 it finishes dead last, *worse than
random search* (2.01 vs 0.63); its crowding distance actively
misleads in 10-D.
- HypE / MOEA/D / GrEA / IBEA barely notice the 4 -> 10 jump.
- GrEA wins DTLZ1-8, consistent with the 3-objective DTLZ1 table.
- HypE reverses: #1 on both DTLZ2 tables, #6 on the deceptive DTLZ1-8.
Regenerated examples/compare-results.md with the three new sections.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The `compare` harness contradicts two recommendations in the decision
trees:
- "Disconnected or non-convex front -> AGE-MOEA, KnEA, IBEA" had it
backwards. Added KnEA to the ZDT3 table (the disconnected-front
benchmark) so the claim is actually exercised: AGE-MOEA and KnEA
finish *last and second-last*; IBEA wins, MOEA/D and NSGA-II follow.
The trees now split "disconnected" from "non-convex contiguous",
lead disconnected with IBEA, and note the geometry-aware methods
trail when the front is in pieces.
- The book filed Simulated Annealing on permutations as a "one-decision
baseline" and led the JSS row with GA. On the harness SA *wins* the
FT06 job-shop table and ties for the TSP optimum; SA/Tabu edge out
the GA. Reframed SA/Tabu as strong sequencing methods.
Also regenerated examples/compare-results.md for the new ZDT3 row.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The terminal output was misaligned: headers and data were right-aligned
with hardcoded column widths and separator lengths, and the mean ± std
cells contained the non-ASCII `±` (plus `ε`, `↑`, `↓`) -- on any terminal
that renders those at a non-1 column width the columns drift, and the
hardcoded `-`.repeat(n) separators didn't match the real table width
anyway.
Changes:
- New `print_table` helper: column widths derived from the actual cell
contents (header + every row), separator length computed to match.
- All table cells are now ASCII: `+/-` instead of `±`, `eps-MOEA`
instead of `ε-MOEA`, arrows dropped from headers.
- Every table is sorted best-first by its primary quality metric.
- Added three combinatorial / sequencing problems with their own
(permutation- / bitstring-native) algorithm rosters: a convex-position
ring TSP (known optimum), FT06 job-shop makespan (known optimum 55),
and a bi-objective 0/1 knapsack scored by hypervolume.
- Expanded every problem's preamble: what it is, why it's hard, and the
best-known / optimal result.
- Regenerated examples/compare-results.md to match.
Continuous-problem quality metrics are unchanged (bit-identical to prior
snapshots); only ms columns and row order move.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
CHANGELOG entry consolidates the unreleased work since v0.3.0:
testing-infrastructure expansion (proptest suites, cargo-fuzz
harness, stability tests, gungraun benches, CI), two real bug
fixes the testing surfaced (NaN-cycle non_dominated_sort, simplex
projection magnitude precision), the README decision-tree update
against the v0.3.0 comparison data, and the v0.4.0 perf pass
(cumulative compare harness 18.6 s → 5.7 s, 3.27×).
`examples/compare-results.md` refreshed with the post-perf-pass
ms numbers; quality metrics are bit-identical to the v0.3.0
snapshot (the perf pass was strictly CPU time, never algorithmic).
Snapshot of `cargo run --release --example compare` after the v0.3.0
algorithm cohort. The harness runs 7 benchmark problems × ~20
algorithms × 10 seeds each (≈3 minutes wall-clock); this file is the
reference output so readers can scan results without running it
themselves.
Highlights worth reading even if you're skipping the file:
- ZDT1: MOPSO and MOEA/D dominate convergence; (1+1)-ES and DE tie
at f = 0 on Rastrigin
- IPOP-CMA-ES drops vanilla CMA-ES from f=2.35 to f=0.13 on
Rastrigin (the multimodal failure-mode it was added to fix)
- IBEA wins DTLZ2 (15× closer to true front than NSGA-III)
- GrEA wins DTLZ1 (linear simplex front matches grid-based niching)
- Nelder-Mead = 0 exactly on Rosenbrock; CMA-ES at machine epsilon
- Bayesian optimization at 60 evals is honestly bad on 5-D problems
with the default kernel — flagged so readers don't conclude BO is
weak in general; it just needs more evals or hyperparameter tuning
swaitsandClaude Opus 4.7