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omnibias.dynamics

Computer-assisted dynamics on the validated tower. Rigorous (interval / Taylor-model) tools for nonlinear dynamical systems, built on the QR-Lohner validated flow and the radii-polynomial existence machinery in omnibias.core.verified.

import omnibias.dynamics as od
Sound by construction

An enclosure provably contains the true object, and an existence claim is a proof, never a heuristic.

Variational / monodromy flow

Propagate a state and its fundamental (variational) matrix rigorously — the basis for Floquet / stability analysis.

SymbolRole
variational_flow, variational_steprigorous state + variational-matrix flow
VariationalStatethe enclosed state container
step_transition_matrixper-step transition matrix enclosure
monodromy_matrix, monodromy_trace, monodromy_determinantmonodromy quantities
spectral_radius_boundenclosure of the spectral radius

Poincaré sections

PoincareSection · PoincareCrossing · poincare_map — a rigorous return map across a hyperplane.

Certified Lyapunov bounds

certified_lyapunov_exponentLyapunovBounds — two-sided enclosures of the leading Lyapunov exponent from the validated variational flow.

Periodic-orbit proofs

prove_periodic_orbitPeriodicOrbitCertificate — a radii-polynomial proof that a true periodic orbit lives in an explicit ball around a numerical guess.

Example systems

harmonic_oscillator · linear_system · radial_logistic · hopf_normal_form — ready-made vector fields for trying the tools.

Example

from omnibias.dynamics import prove_periodic_orbit, hopf_normal_form

cert = prove_periodic_orbit(hopf_normal_form(mu=0.5), guess=initial_loop)
print(cert) # proven / not proven, with the enclosing ball radius

See also