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Configure time integration

TimeIntegration is the supported Poscidyn solver. It integrates the first order state system with Diffrax's adaptive Tsit5 method, estimates a transient duration, and retains a final time window for analysis.

Important settings

  • rtol, atol: relative and absolute tolerances for adaptive integration.
  • max_steps: hard upper limit on internal integration steps per trajectory.
  • n_time_steps: saved samples per retained period block. Set it explicitly when you need predictable resolution or use JIT/vmap around the call.
  • periods_to_retain: number of final drive periods retained for a periodic response. The default is 4.
  • t_steady_state_factor: safety factor multiplying the oscillator's linear-model transient estimate.
  • max_order_superharmonics: used only when Poscidyn estimates n_time_steps automatically.
  • throw: if True, integration failures are raised by Diffrax instead of being represented in sweep statistics.

A defensible tuning sequence

Begin with a representative time_response and inspect the transient. Then set n_time_steps high enough to resolve the highest response content relevant to the study. Finally, tighten tolerances or raise max_steps only after checking that numerical failures or visible sampling artefacts justify it.

For frequency sweeps, non-finite trajectories are counted in result.stats. Do not use an attractive selected curve to hide a poor completion rate.

The time-response quickstart shows the minimal construction; limitations explains the transient and computational assumptions.