Van der Pol (μ=10⁴)

PARITYS3 · dim 2

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 maximum-stiffness Van der Pol oscillator used as an integrator stress test. Included as a parity case — both SolvSRK and the best SciPy arm survive noise here.

Oscillators & nonlinear dynamics

Problem definition

Van der Pol (1920); Hairer–Wanner II §IV.2

Math used in the published benchmark cell — so you can confirm the name matches the ODE you expect. Not a runnable fixture.

ẋ = v
v̇ = μ (1 − x²) v − x
Parameters
  • μ = 10⁴
Initial condition
(x, v)(0) = (2, 0)
Horizon
t ∈ [0, 2]

Extreme-stiffness Van der Pol. Distinct from milder catalog entries (μ = 1, 100, 1000).

Fingerprint

Spread: extreme

Default noise: clean

Recommendation snapshot

Clean best: SciPy Radau (precision)

Noisy best: parity (SolvSRK ≈ SciPy)

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: Van der Pol (μ=10⁴) (vdpol_1e4)

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
1SciPy RadauSciPy
100%
15.31503 ms0.985
2SolvSRK
100%
12.7583318 ms0.922
3SciPy LSODASciPy
100%
10.799<1 ms0.874
4SciPy RK23SciPy
100%
9.471,693559 ms0.844
5SciPy RK45SciPy
100%
9.3126,878755 ms0.840
6Tsit5external
100%
9.0130,62010.51 s0.834
7SciPy BDFSciPy
100%
9.01375 ms0.833
8CVODE BDFexternal
100%
8.9736 ms0.831
9CVODE Adamsexternal
100%
8.82357 ms0.828
10SciPy DOP853SciPy
100%
8.5112,754610 ms0.821

At Clean, best balanced arm is SciPy Radau · SolvSRK survival 100%, SCD 12.7.

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 →

SolvScout · free

Profile your problem for free

This page shows one published benchmark cell. SolvScout fingerprints your ODE, compares it to the full corpus, and recommends a solver with the same survival / precision / speed ranking you see here — including when a SciPy arm wins.

SolvSRK · 30-day trial

Run the winner on your machine

SolvSRK is the stiffness-adaptive integrator behind the SolvSRK column in these tables. Create an account, activate a machine, and take a 30-day trial — same binary you'd ship after purchase.

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_vdpol_1e4_2026,
  title        = {Resonix Evidence Portal: Van der Pol (μ=10⁴)},
  author       = {{Resonix Labs (Canada) Inc.}},
  year         = {2026},
  howpublished = {\url{https://resonix.tech/evidence/problems/vdpol_1e4}},
  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