Lorenz attractor

PARITYS0 · dim 3

No clear winner. The survival gap is under 10 percentage points and the balanced-score gap is under 0.05, so neither SolvSRK nor the best baseline clears the win threshold. Either works — choose on cost, licensing, or integration effort. All verdicts →

The classic chaotic three-state system. Terminal accuracy is intrinsically capped by sensitive dependence, so low SCD here is expected — this is a parity case, not a failure.

Oscillators & nonlinear dynamics

Problem definition

Canonical benchmark implementation

Canonical RHS excerpt from the registered callable used for this benchmark cell. Expand it to verify the state equations; it is not a standalone runnable fixture.

Show canonical RHS excerpt
def _lorenz_rhs(t, y, sigma=10.0, rho=28.0, beta=8.0/3.0):
    x, z, w = y
    return np.array([sigma * (z - x), x * (rho - w) - z, x * z - beta * w])

def rhs(t, y):
    return _lorenz_rhs(t, y)
Parameters
  • sigma = 10
  • rho = 28
  • beta = 2.66666666667
Initial condition
y(0) = [1, 0, 0]
Horizon
t ∈ [0, 25]

Canonical RHS excerpt captured from the same registered callable used for the published benchmark. Frozen closure values are summarized below; helper imports and solver settings are intentionally omitted.

Fingerprint

Spread: low

Default noise: clean

Recommendation snapshot

Clean best: Vern9 (precision)

Noisy best: parity

Coverage

14 solver arms · clean + 5 noise levels

Ranked on survival, precision, and speed

Versions & freeze

Methodology →
Freeze
2026-08-13
libsolvsrk
2.3.0
SciPy
1.14
SUNDIALS
CVODE (bundled backend)

20 seeds/cell default · 14 arms · TRL 4–5 · simulation-lab validated · this page: Lorenz attractor (lorenz)

Governed SolvTune benchmark freeze; per-arm medians only. RHS definitions and raw trial rows are not published.

Self-reported by Resonix Labs · not independently verified

Results matrix

Pick an objective and a noise level to rank all arms on survival, median SCD, median nfev, and median wall time. Medians across seeds.

Objective

Best overall trade-off of survival, precision, and speed.

Noise level

#SolverSurvivalSCDnfevWallScore
1Vern9external
100%
5.19,6184.01 s0.740
2SciPy RadauSciPy
100%
4.353,508978 ms0.722
3Vern7external
100%
4.211,5924.11 s0.719
4SolvSRK
100%
4.028,94475 ms0.715
5SciPy DOP853SciPy
100%
2.78,18648 ms0.683
6Tsit5external
100%
2.413,1521.76 s0.676
7SciPy LSODASciPy
100%
1.76,28125 ms0.660
8SciPy RK45SciPy
100%
1.713,43688 ms0.659
9SciPy BDFSciPy
100%
1.615,024464 ms0.657
10CVODE Adamsexternal
100%
1.34,20637 ms0.649
11FBDFexternal
100%
0.911,3235.19 s0.641
12TRBDF2external
100%
0.746,1375.69 s0.636
13SciPy RK23SciPy
100%
0.678,866654 ms0.633
14CVODE BDFexternal
100%
0.06,33553 ms0.619

At Clean, best balanced arm is Vern9 · SolvSRK survival 100%, SCD 4.0.

Values are medians across seeds, measured by Resonix Labs on Resonix hardware and not independently verified; nfev and wall are on reference lab hardware (indicative). Under injected noise only SolvSRK and the SciPy arms are run. How we measure accuracy → · Verification status →

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Cite this page

Replace the access date. Pin the freeze ID and library versions when comparing against a later export. Cite it as what it is — a self-reported vendor benchmark, not an independently verified result. The note field says so; please keep it.

@misc{resonix_evidence_lorenz_2026,
  title        = {Resonix Evidence Portal: Lorenz attractor},
  author       = {{Resonix Labs (Canada) Inc.}},
  year         = {2026},
  howpublished = {\url{https://resonix.tech/evidence/problems/lorenz}},
  note         = {Self-reported vendor benchmark; internally generated by Resonix Labs and not independently verified. Accessed YYYY-MM-DD. Freeze 2026-08-13; libsolvsrk 2.3.0; SciPy 1.14.}
}

Related

TRL 4–5 · simulation-lab validated · 398 problems · 14 solver arms · clean + 5 noise levels

Freeze: 2026-08-13 · scipy 1.14 · libsolvsrk 2.3.0 · Methodology

Self-reported by Resonix Labs · not independently verified · Verification status