Lotka–Volterra predator–prey

DISADVANTAGES0 · dim 2

A baseline wins. At the comparison noise level, the best baseline beats SolvSRK by at least 10 percentage points of survival, or by at least 0.05 balanced score when survival is tied. Use the winning baseline named on the problem page — not SolvSRK. All verdicts →

The classic two-species ecological oscillator with periodic orbits. A second disadvantage case: SciPy is both more precise on clean runs and more robust under noise.

Oscillators & nonlinear dynamics

Problem definition

Lotka (1925); Volterra (1926)

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

ẋ = a x − b x z
ż = d x z − c z
Parameters
  • a = 1.5
  • b = 1
  • c = 3
  • d = 1
Initial condition
(x, z)(0) = (1, 1)
Horizon
t ∈ [0, 20]

Conservative predator–prey form used in the freeze (Hamiltonian structure).

Fingerprint

Spread: low

Default noise: clean

Recommendation snapshot

Clean best: SciPy Radau (precision)

Noisy best: 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: Lotka–Volterra predator–prey (lotka_volterra)

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%
8.611,548215 ms0.823
2SolvSRK
100%
8.36,80325 ms0.817
3Vern7external
100%
8.22,1423.82 s0.815
4Vern9external
100%
7.71,9063.84 s0.802
5Tsit5external
100%
6.92,682921 ms0.784
6SciPy RK45SciPy
100%
6.82,51016 ms0.781
7SciPy DOP853SciPy
100%
6.72,00612 ms0.777
8SciPy LSODASciPy
100%
6.21,3775 ms0.767
9FBDFexternal
100%
6.12,2514.86 s0.764
10SciPy RK23SciPy
100%
6.116,823136 ms0.763
11SciPy BDFSciPy
100%
5.43,641110 ms0.748
12CVODE Adamsexternal
100%
5.21,07114 ms0.744
13CVODE BDFexternal
100%
5.11,46517 ms0.739
14TRBDF2external
100%
3.213,3715.15 s0.696

At Clean, best balanced arm is SciPy Radau · SolvSRK survival 100%, SCD 8.3.

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_lotka_volterra_2026,
  title        = {Resonix Evidence Portal: Lotka–Volterra predator–prey},
  author       = {{Resonix Labs (Canada) Inc.}},
  year         = {2026},
  howpublished = {\url{https://resonix.tech/evidence/problems/lotka_volterra}},
  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